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Publisher: Elsevier   (Total: 3182 journals)

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Showing 1 - 200 of 3182 Journals sorted alphabetically
Academic Pediatrics     Hybrid Journal   (Followers: 38, SJR: 1.655, CiteScore: 2)
Academic Radiology     Hybrid Journal   (Followers: 26, SJR: 1.015, CiteScore: 2)
Accident Analysis & Prevention     Partially Free   (Followers: 102, SJR: 1.462, CiteScore: 3)
Accounting Forum     Hybrid Journal   (Followers: 28, SJR: 0.932, CiteScore: 2)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 40, SJR: 1.771, CiteScore: 3)
Achievements in the Life Sciences     Open Access   (Followers: 7)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 6)
Acta Astronautica     Hybrid Journal   (Followers: 437, SJR: 0.758, CiteScore: 2)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 2)
Acta Biomaterialia     Hybrid Journal   (Followers: 28, SJR: 1.967, CiteScore: 7)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 3)
Acta de Investigación Psicológica     Open Access   (Followers: 3)
Acta Ecologica Sinica     Open Access   (Followers: 11, SJR: 0.18, CiteScore: 1)
Acta Histochemica     Hybrid Journal   (Followers: 6, SJR: 0.661, CiteScore: 2)
Acta Materialia     Hybrid Journal   (Followers: 314, SJR: 3.263, CiteScore: 6)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 5, SJR: 0.504, CiteScore: 1)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.542, CiteScore: 1)
Acta Oecologica     Hybrid Journal   (Followers: 12, SJR: 0.834, CiteScore: 2)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription  
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 2, SJR: 0.307, CiteScore: 0)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 1, SJR: 1.793, CiteScore: 6)
Acta Poética     Open Access   (Followers: 4, SJR: 0.101, CiteScore: 0)
Acta Psychologica     Hybrid Journal   (Followers: 26, SJR: 1.331, CiteScore: 2)
Acta Sociológica     Open Access   (Followers: 1)
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.052, CiteScore: 2)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 3, SJR: 0.374, CiteScore: 1)
Actas Dermo-Sifiliográficas (English Edition)     Full-text available via subscription   (Followers: 2)
Actas Urológicas Españolas     Full-text available via subscription   (Followers: 3, SJR: 0.344, CiteScore: 1)
Actas Urológicas Españolas (English Edition)     Full-text available via subscription   (Followers: 1)
Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 7, SJR: 0.19, CiteScore: 0)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 3)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 8)
Acute Pain     Full-text available via subscription   (Followers: 15, SJR: 2.671, CiteScore: 5)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.53, CiteScore: 4)
Addictive Behaviors     Hybrid Journal   (Followers: 18, SJR: 1.29, CiteScore: 3)
Addictive Behaviors Reports     Open Access   (Followers: 9, SJR: 0.755, CiteScore: 2)
Additive Manufacturing     Hybrid Journal   (Followers: 11, SJR: 2.611, CiteScore: 8)
Additives for Polymers     Full-text available via subscription   (Followers: 23)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 184, SJR: 4.09, CiteScore: 13)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 12, SJR: 1.167, CiteScore: 4)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.694, CiteScore: 3)
Advances in Accounting     Hybrid Journal   (Followers: 9, SJR: 0.277, CiteScore: 1)
Advances in Agronomy     Full-text available via subscription   (Followers: 17, SJR: 2.384, CiteScore: 5)
Advances in Anesthesia     Full-text available via subscription   (Followers: 29, SJR: 0.126, CiteScore: 0)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 2)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 12, SJR: 0.992, CiteScore: 1)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 12, SJR: 1.551, CiteScore: 4)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 24, SJR: 2.089, CiteScore: 5)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 15, SJR: 0.572, CiteScore: 2)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.61, CiteScore: 7)
Advances in Botanical Research     Full-text available via subscription   (Followers: 2, SJR: 0.686, CiteScore: 2)
Advances in Cancer Research     Full-text available via subscription   (Followers: 34, SJR: 3.043, CiteScore: 6)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 1.453, CiteScore: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 1.992, CiteScore: 5)
Advances in Cell Aging and Gerontology     Full-text available via subscription   (Followers: 5)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 14)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 29, SJR: 0.156, CiteScore: 1)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 11, SJR: 0.713, CiteScore: 1)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 10, SJR: 1.316, CiteScore: 2)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 26, SJR: 1.562, CiteScore: 3)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 20, SJR: 1.977, CiteScore: 8)
Advances in Computers     Full-text available via subscription   (Followers: 14, SJR: 0.205, CiteScore: 1)
Advances in Dermatology     Full-text available via subscription   (Followers: 15)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 13)
Advances in Digestive Medicine     Open Access   (Followers: 12)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 7)
Advances in Drug Research     Full-text available via subscription   (Followers: 26)
Advances in Ecological Research     Full-text available via subscription   (Followers: 43, SJR: 2.524, CiteScore: 4)
Advances in Engineering Software     Hybrid Journal   (Followers: 29, SJR: 1.159, CiteScore: 4)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 8)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 51, SJR: 5.39, CiteScore: 8)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 1)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 66, SJR: 0.591, CiteScore: 2)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 17)
Advances in Genetics     Full-text available via subscription   (Followers: 21, SJR: 1.354, CiteScore: 4)
Advances in Genome Biology     Full-text available via subscription   (Followers: 10, SJR: 12.74, CiteScore: 13)
Advances in Geophysics     Full-text available via subscription   (Followers: 7, SJR: 1.193, CiteScore: 3)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 26, SJR: 0.368, CiteScore: 1)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 11, SJR: 0.749, CiteScore: 3)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 25)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 3, SJR: 0.193, CiteScore: 0)
Advances in Immunology     Full-text available via subscription   (Followers: 37, SJR: 4.433, CiteScore: 6)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 10, SJR: 1.163, CiteScore: 2)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 2, SJR: 1.938, CiteScore: 3)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 6, SJR: 0.176, CiteScore: 0)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 3)
Advances in Life Course Research     Hybrid Journal   (Followers: 9, SJR: 0.682, CiteScore: 2)
Advances in Lipobiology     Full-text available via subscription   (Followers: 1)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Marine Biology     Full-text available via subscription   (Followers: 21, SJR: 0.88, CiteScore: 2)
Advances in Mathematics     Full-text available via subscription   (Followers: 14, SJR: 3.027, CiteScore: 2)
Advances in Medical Sciences     Hybrid Journal   (Followers: 8, SJR: 0.694, CiteScore: 2)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 5, SJR: 1.158, CiteScore: 3)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 24)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 8)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 7, SJR: 0.182, CiteScore: 0)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 5)
Advances in Oncobiology     Full-text available via subscription   (Followers: 2)
Advances in Organ Biology     Full-text available via subscription   (Followers: 2)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 18, SJR: 1.875, CiteScore: 4)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.174, CiteScore: 0)
Advances in Parasitology     Full-text available via subscription   (Followers: 5, SJR: 1.579, CiteScore: 4)
Advances in Pediatrics     Full-text available via subscription   (Followers: 27, SJR: 0.461, CiteScore: 1)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 19)
Advances in Pharmacology     Full-text available via subscription   (Followers: 17, SJR: 1.536, CiteScore: 3)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 9, SJR: 0.574, CiteScore: 1)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.109, CiteScore: 1)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 10)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 6)
Advances in Porous Media     Full-text available via subscription   (Followers: 5)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 19)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20, SJR: 0.791, CiteScore: 2)
Advances in Psychology     Full-text available via subscription   (Followers: 67)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6, SJR: 0.371, CiteScore: 1)
Advances in Radiation Oncology     Open Access   (Followers: 1, SJR: 0.263, CiteScore: 1)
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 3, SJR: 0.101, CiteScore: 0)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 6)
Advances in Space Research     Full-text available via subscription   (Followers: 422, SJR: 0.569, CiteScore: 2)
Advances in Structural Biology     Full-text available via subscription   (Followers: 5)
Advances in Surgery     Full-text available via subscription   (Followers: 13, SJR: 0.555, CiteScore: 2)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 37, SJR: 2.208, CiteScore: 4)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 20)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 15)
Advances in Virus Research     Full-text available via subscription   (Followers: 6, SJR: 2.262, CiteScore: 5)
Advances in Water Resources     Hybrid Journal   (Followers: 54, SJR: 1.551, CiteScore: 3)
Aeolian Research     Hybrid Journal   (Followers: 6, SJR: 1.117, CiteScore: 3)
Aerospace Science and Technology     Hybrid Journal   (Followers: 385, SJR: 0.796, CiteScore: 3)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.42, CiteScore: 2)
African J. of Emergency Medicine     Open Access   (Followers: 6, SJR: 0.296, CiteScore: 0)
Ageing Research Reviews     Hybrid Journal   (Followers: 12, SJR: 3.671, CiteScore: 9)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 477, SJR: 1.238, CiteScore: 3)
Agri Gene     Hybrid Journal   (Followers: 1, SJR: 0.13, CiteScore: 0)
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 18, SJR: 1.818, CiteScore: 5)
Agricultural Systems     Hybrid Journal   (Followers: 31, SJR: 1.156, CiteScore: 4)
Agricultural Water Management     Hybrid Journal   (Followers: 44, SJR: 1.272, CiteScore: 3)
Agriculture and Agricultural Science Procedia     Open Access   (Followers: 4)
Agriculture and Natural Resources     Open Access   (Followers: 3)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 58, SJR: 1.747, CiteScore: 4)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.589, CiteScore: 3)
Air Medical J.     Hybrid Journal   (Followers: 8, SJR: 0.26, CiteScore: 0)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.19, CiteScore: 0)
Alcohol     Hybrid Journal   (Followers: 12, SJR: 1.153, CiteScore: 3)
Alcoholism and Drug Addiction     Open Access   (Followers: 12)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 2, SJR: 0.604, CiteScore: 3)
Alexandria J. of Medicine     Open Access   (Followers: 1, SJR: 0.191, CiteScore: 1)
Algal Research     Partially Free   (Followers: 11, SJR: 1.142, CiteScore: 4)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.504, CiteScore: 1)
Allergology Intl.     Open Access   (Followers: 5, SJR: 1.148, CiteScore: 2)
Alpha Omegan     Full-text available via subscription   (SJR: 3.521, CiteScore: 6)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 10, SJR: 0.201, CiteScore: 1)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 53, SJR: 4.66, CiteScore: 10)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 6, SJR: 1.796, CiteScore: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 6, SJR: 1.108, CiteScore: 3)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 5)
American Heart J.     Hybrid Journal   (Followers: 58, SJR: 3.267, CiteScore: 4)
American J. of Cardiology     Hybrid Journal   (Followers: 63, SJR: 1.93, CiteScore: 3)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 46, SJR: 0.604, CiteScore: 1)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 12)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 14, SJR: 1.524, CiteScore: 3)
American J. of Human Genetics     Hybrid Journal   (Followers: 37, SJR: 7.45, CiteScore: 8)
American J. of Infection Control     Hybrid Journal   (Followers: 29, SJR: 1.062, CiteScore: 2)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 36, SJR: 2.973, CiteScore: 4)
American J. of Medicine     Hybrid Journal   (Followers: 50)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3, SJR: 1.967, CiteScore: 2)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 255, SJR: 2.7, CiteScore: 4)
American J. of Ophthalmology     Hybrid Journal   (Followers: 66, SJR: 3.184, CiteScore: 4)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 5, SJR: 0.265, CiteScore: 0)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.289, CiteScore: 1)
American J. of Otolaryngology     Hybrid Journal   (Followers: 25, SJR: 0.59, CiteScore: 1)
American J. of Pathology     Hybrid Journal   (Followers: 33, SJR: 2.139, CiteScore: 4)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 28, SJR: 2.164, CiteScore: 4)
American J. of Surgery     Hybrid Journal   (Followers: 39, SJR: 1.141, CiteScore: 2)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.767, CiteScore: 1)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 7)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.144, CiteScore: 3)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 66, SJR: 0.138, CiteScore: 0)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 24, SJR: 0.411, CiteScore: 1)
Anales de Cirugia Vascular     Full-text available via subscription   (Followers: 1)
Anales de Pediatría     Full-text available via subscription   (Followers: 3, SJR: 0.277, CiteScore: 0)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription  
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 5, SJR: 4.849, CiteScore: 10)
Analytica Chimica Acta     Hybrid Journal   (Followers: 44, SJR: 1.512, CiteScore: 5)
Analytica Chimica Acta : X     Open Access  
Analytical Biochemistry     Hybrid Journal   (Followers: 209, SJR: 0.633, CiteScore: 2)
Analytical Chemistry Research     Open Access   (Followers: 13, SJR: 0.411, CiteScore: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 14)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 2)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 25, SJR: 0.683, CiteScore: 2)
Angiología     Full-text available via subscription   (SJR: 0.121, CiteScore: 0)
Angiologia e Cirurgia Vascular     Open Access   (Followers: 1, SJR: 0.111, CiteScore: 0)
Animal Behaviour     Hybrid Journal   (Followers: 224, SJR: 1.58, CiteScore: 3)
Animal Feed Science and Technology     Hybrid Journal   (Followers: 6, SJR: 0.937, CiteScore: 2)
Animal Reproduction Science     Hybrid Journal   (Followers: 7, SJR: 0.704, CiteScore: 2)

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Similar Journals
Journal Cover
International Journal of Biological Macromolecules
Journal Prestige (SJR): 0.917
Citation Impact (citeScore): 4
Number of Followers: 2  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0141-8130
Published by Elsevier Homepage  [3182 journals]
  • Local and systemic effects of BtaMP-1, a new weakly hemorrhagic Snake
           Venom Metalloproteinase purified from Bothriopsis taeniata Snake Venom
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Frank Denis Torres-Huaco, Silvana Maruñak, Pamela Teibler, Soledad Bustillo, Ofelia Acosta de Pérez, Laura Cristina Leiva, Luis Alberto Ponce-Soto, Sergio Marangoni A new weak hemorrhagic metalloproteinase named BtaMP-1 was purified from Bothriopsis taeniata snake venom by molecular exclusion followed by anion exchange chromatographies. This protein showed a molecular mass of 25,968.16 Da and is composed of 218 amino acid residues. The multiple alignments of its partial amino acid sequence showed high structural identity with other P-I class SVMP. BtaMP-1 showed caseinolytic activity that was enhanced by Ca2+ ion, completely inhibited by chelating and reducing agents and can be classified as an α-fibrinogenolytic enzyme. Locally, BtaMP-1 induces hemorrhage and edema, but not myotoxicity. These findings were confirmed by histological analysis of mouse gastrocnemius muscle. “In vitro” studies suggest that BtaMP-1 induce cytotoxicity in myoblast C2C12 but not in the myotubes cell line. BtaMP-1 induced systemic alterations in mice with one MHD and two hours exposure; histological analysis of lungs showed hemorrhagic areas, congestion, and increase the thickness of alveolar septum. Also, this protein induced mild effects on kidney and disruption of coagulation by depletion of fibrinogen plasma levels. This work provides insights into the importance of BtaMP-1 biological effects in envenomation by Bothropsis taeniata snake venom and providing further evidence to understand the role of P-I class SVMP in ophidian envenomation.
       
  • Influence of chitosan/1,4-butanediol blends on the thermal and surface
           behavior of polycaprolactone diol-based polyurethanes
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Muhammad Asif Javaid, Khalid Mahmood Zia, Hafiza Nabila Ilyas, Sidra, Nazia Yaqub, Ijaz Ahmad Bhatti, Mohamed Rehan, Muhammad Shoaib, Ali Bahadur This current study aims to study of the thermal behavior of the polyurethane elastomers (PUEs) by varying blends of 1, 4-butanediol and chitosan (CS) into the backbone of polyurethane (PU). The polycaprolactone diol (PCL) was used as a macrodiol while a mixture of CS and 1, 4-butanediol was reacted to extend the polymer. For the preparation of NCO-endcapped polyurethane prepolymer; one equivalent of PCL was reacted with three equivalents of toluene diisocyanate (TDI). The obtained pre-polymer was further extended with CS and 1, 4-butanediol (2 mol) individually and with different blends. The characterization of the structure was determined using FTIR and NMR spectroscopy. The glass transition temperature of prepared polyurethanes was measured by differential scanning calorimetry (DSC). The results obtained showed that, the thermal behavior of PUs was enhanced as the CS contents were increased in the PU backbone. The crystalline behavior of CS increased the hydrophobicity of the prepared PUs. Moreover; the water absorption, contact angle, swelling behavior, work of water adhesion and surface free energy of the synthesized PUs were affected with the addition of chitosan. Finally, it has been concluded resultant chitosan based PU has a potential for biomedical implant i.e., non-absorbable suture.Graphical abstractUnlabelled Image
       
  • Crystal structure and ligand identification of odorant binding protein 4
           in the natural predator Chrysopa pallens
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Ting-Ting Li, Wen-Cheng Liu, Jiang Zhu, Yun-Huang Yang, Chao Ma, Chen Lu, Kun-Xiao Zhang Green lacewing Chrysopa pallens (Rambur) is a general predator of many agricultural pests and plays a pivotal role in reducing crop damage by managing insect pest populations. Odorant binding proteins (OBPs) in insects can sense the semiochemicals in the environment and initiate the delivery of signals to their receptors. However, no Chrysopa pallens OBP (CpalOBP) structure has been reported yet, and their corresponding candidate semiochemicals are still largely unknown. Here, we reported the structure of CpalOBP4 solved with X-ray diffraction and showed its potential ligands. Our results showed that CpalOBP4 has a classical OBP structure with six α-helices and three disulfide bridges, and it can bind with farnesene, 2-tridecanone, cis-3-hexenyl hexanoate, nerolidol and farnesol through a central hydrophobic cavity. Our molecular docking results showed that Met31, Met78, Leu98, Phe141, Leu142 and Pro143 in the hydrophobic cavity were the key residues mediating the interaction of CpalOBP4 with farnesene, 2-tridecanone and cis-3-hexenyl hexanoate, which was further proven by the results that mutations of these residues led to significantly reduced binding affinities of CpalOBP4 for these ligands. Our study provides useful information for the further investigation of the biological function of CpalOBP4 as well as important cues for improving biological control in agriculture.
       
  • Biodegradable reduction-responsive polymeric micelles for enhanced
           delivery of melphalan to retinoblastoma cells
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Jia Li, Jihong Wang, Xuetong Zhang, Xin Xia, Chenchen Zhang Melphalan (MEL) is an effective chemotherapeutic agent for treatment of retinoblastoma (Rb) which is the most common childhood malignancy. However, the inherent cardiopulmonary toxicity and hazardous integration limit its therapeutic effect on RB. N-Acetylheparosan (AH), a natural heparin-like polysaccharide in mammals with long circulation effect and good biocompatibility, was linked by d-α-tocopherol acid succinate (VES) via and cystamine (CYS) to synthesize reduction-responsive N-acetylheparosan-CYS-Vitamin E succinate (AHV) copolymers. In addition, CYS was replaced by adipic acid dihydrazide (ADH) to obtain a control of non-reduction-responsive polymers N-acetylheparosan-ADH-Vitamin E succinate (ADV). MEL-loaded AHV micelles (MEL/AHV) as well as ADV micelles (MEL/ADV) were prepared with small particle size and high drug loading content. In vitro drug release showed that MEL/AHV micelles presented obvious reduction-triggered release behavior compared with MEL/ADV. In vitro antitumor effects were investigated using WERI-Rb-1 retinoblastoma cells. Cytotoxicity experiments showed that the IC50 of MEL/AHV was significantly lower than that of free MEL and MEL/ADV, suggesting that MEL/AHV enhanced the cytotoxicity against retinoblastoma cells. Furthermore, MEL/AHV micelles were more easily uptaken by multiple pathways compared with MEL/ADV and free MEL. Therefore, MEL/AHV might be a potential delivery system for enhanced delivery of melphalan to Rb cells.
       
  • Hydrophobic-modified montmorillonite coating onto crosslinked chitosan as
           the core-shell micro-sorbent for iodide adsorptive removal via Pickering
           emulsion polymerization
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Qing Li, Qian Mao, Chen Yang, Shengjie Zhang, Gaohong He, Xiujuan Zhang, Wenjun Zhang The radioactive iodine from nuclear wastes caused severe environmental contamination and public health concern. Chitosan and montmorillonite as green materials of the favorable adsorptivity were proposed for iodine treatment. Rather than intercalation, the crosslinked chitosan proposedly via Pickering emulsion polymerization was coated by hydrophobical-modified montmorillonite (HMMT) to form the micro-composite of chitosan/HMMT (CTS/HMMT) as the iodide adsorbent of eco-safety, adsorptivity combination and chitosan-swelling limitation. From pH 3 to 10, CTS/HMMTs adsorbed I127 anions no
       
  • Annealing improves the concentration and controlled release of
           encapsulated ethylene in V-type starch
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Linfan Shi, Bin Zhang, Chao Li, Xiong Fu, Qiang Huang Ethylene gas was introduced into annealed V-type crystalline starches (V-starches). The morphological and structural properties of the inclusion complexes (ICs) were characterized using scanning electron microscopy, light microscopy, X-ray diffractometry, and 13C solid-state nuclear magnetic resonance spectroscopy. The ethylene concentration in ICs annealed at 70 °C and 50% (v/v) ethanol increased from 8.0‐31.8% (w/w) to 18.1–49.6% (w/w). The controlled release characteristics of ICs were also investigated under various temperature and relative humidity conditions by fitting to the Avrami equation. ICs prepared with annealed V-starches were more stable in different storage environments, which may be due to well-formed helices with higher crystallinity and larger crystallite size. Thus, annealing is an important heat treatment technique with potential for material modification.
       
  • Crystal structure of BinAB toxin receptor (Cqm1) protein and molecular
           dynamics simulations reveal the role of unique Ca(II) ion
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Mahima Sharma, Vinay Kumar Glycoside hydrolase 13 (GH13) family represents a large and diverse enzyme family. Cqm1, an amylomaltase of Culex mosquito, belongs to the GH13 family and subfamily 17 (GH13_17). The protein acts as the receptor for mosquito-larvicidal BinAB toxin that is used world-wide for control of the mosquito population. The protein was crystallized in the presence of a mixture of divalent metal ions. Cqm1 crystal structure was solved using the MRSAD method using Cd(II) anomalous at 1.9 Å wavelength and the structure was refined against 1.8 Å synchrotron data. One tightly bound Ca(II) ion in each of the monomer was observed and this site is suggested here to be unique to the GH13_17 family. Molecular dynamics simulations provide clues for the functional role of Ca(II) ion shown earlier to be essential for enzymatic activity. An optimized substrate (maltotriose) bound structure of the complex was constructed based on which ‘retaining-type’ mechanism can be predicted reliably. It reveals large conformational change in aromatic residues situated at active-site entrance. A Cd(II) ion was observed overlapping with the substrate-binding site. Kinetics data suggests non-competitive inhibition of Cqm1 by Cd(II). This is the first structure from the GH13_17 family and provides template for constructing reliable models for other members.
       
  • Generalized kinetics for thermal degradation and melt rheology for poly
           (lactic acid)/poly (butylene succinate)/functionalized chitosan based
           reactive nanobiocomposite
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Monika, Neha Mulchandani, Vimal Katiyar Systematic kinetics of melt-blended Poly(lactic acid) (PLA)/Poly(butylene succinate) (PBS) and PLA/PBS/functionalized chitosan (FCH) nanobiocomposites with dicumyl peroxide (DCP) and chemical changes thereof at degradation temperatures are evaluated using thermogravimetry (TGA) and thermogravimetry coupled to Fourier transform infrared spectroscopy (TGA–FTIR). A comprehensive kinetic model is employed on above blended samples, including (i) Flynn–Wall–Ozawa, Kissinger, Kissinger–Akahira–Sunose methods to investigate the kinetic and thermodynamic variables, and (ii) Generalized master plots to propose the thermal-induced mechanism. The thermal stability of PLA/PBS reduced with increasing FCH loading up to 3 wt%, and improved for DCP treated PLA/PBS/1FCH at maximum degradation temperature (Tmax) is noticed. The activation energy estimated from Flynn-Wall-Ozawa method are (129–139 kJmol−1), (116–152 kJmol−1), (109–146 kJmol−1), (132–169 kJmol−1) and (120–166 kJmol−1) for PLA/PBS, PLA/PBS/1FCH, PLA/PBS/3FCH, PLA/PBS/1DFCH and PLA/PBS/3DFCH respectively. The generalized master plots depicts that the PLA/PBS blend exhibited L2–F1 mechanism whereas their nanobiocomposite with or without DCP followed L2–Dn and A2–L2–Dn mechanism respectively. Coupled TGA–FTIR highlights the similar kinds of products such as lactide, acetaldehyde, esters, CO2 and CO liberated during the thermal degradation of PLA/PBS blend and their nanobiocomposites. These crosslinked/branched structures are postulated by the rheological behavior which confirmed increase in the complex viscosity (η*) and storage modulus (G′) of PLA/PBS/D/1FCH.
       
  • Isolation and structural characterization of sulfated polysaccharide from
           Spirulina platensis and its bioactive potential: In vitro antioxidant,
           antibacterial activity and Zebrafish growth and reproductive performance
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Periyannan Rajasekar, Subramanian Palanisamy, Ravichandran Anjali, Manoharan Vinosha, Meyyanathan Elakkiya, Thangapandi Marudhupandi, Mehdi Tabarsa, SangGuan You, Narayanasamy Marimuthu Prabhu In this study, the sulfated polysaccharide (SPs) was isolated from Spirulina platensis. The isolated SPs contains carbohydrate, sulfate, protein and uronic acid at 38.7 ± 0.30%, 21.3 ± 0.87%, 7.1 ± 0.15% and 7.9 ± 0.4% respectively. The elemental analysis confirmed the presence of carbon (18.01 ± 0.10%), hydrogen (1.83 ± 0.02%) and nitrogen (3.43 ± 0.01%). The monosaccharide composition and molecular weight of SPs were analyzed by high-performance liquid chromatography and size exclusion chromatography respectively. The monosaccharide composition analysis showed the existence of glucose, rhamnose, xylose, fucose, mannose, galactose and the molecular weight of SPs was 1016 kDa. Further, the characterization of SPs was done by UV–visible spectroscopy, X-ray diffraction, FT-IR, 1H NMR and 13C NMR analysis. The obtained SPs exhibited potent antioxidant activity in DPPH (76.45 ± 0.49%), reducing power (absorbance: 1.3 ± 0.02), hydrogen peroxide scavenging (66.3 ± 1.16%), hydroxyl scavenging (68.6 ± 3.2%), nitric oxide (81.36 ± 1.85%) and total antioxidant (absorbance:1.66 ± 0.02) activities at 5 mg/ml. In addition, SPs revealed the highest antibacterial efficacy against the pathogenic bacteria Vibrio vulnificus in disc diffusion, agar bioassay and protein leakage assays at 100 μg/ml. Furthermore, the supplementation of 2% SPs through a feed to the Danio rerio fish enhances the growth and reproductive performances. This finding confirmed that the isolated SPs from S. platensis possess pharmaceutical as well as nutritional properties.
       
  • Synthesis, characterization and applications of polyacrylamide grafted
           fenugreek gum (FG-g-PAM) as flocculant: Microwave vs thermal synthesis
           approach
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Sumit Mishra, Koustav Kundu Fenugreek gum is modified using two different techniques: microwave-assisted and thermal synthesis technique of graft copolymerization. The synthesis was done by varying the concentration of acrylamide monomer and CAN initiator to get the best-grafted product. The physicochemical characteristics were determined by elemental analysis, FTIR spectroscopy, SEM, XRD, DSC, TGA, number-average molecular weight and intrinsic viscosity. All the grafted materials were tested by flocculation of different synthetic suspension media as well as river water. The process of deflocculation and refloccculation was also carried out and it was observed that refloccculation process has a good potential as the flocculation efficacy increased to a considerable extent. The flocculation efficacy increased from 92.05% to 94.32% upto a maximum of 95.98% in refloccculation process. The flocculation efficacy was found out to be 95.98%, 40.52% and 68.94% respectively kaolin, coal fine and iron ore suspensions. Flocculation was done in kaolin suspension of pH 2, 4, 7 and 10 and at different temperature range of 100, 250, 400 and 550C. It is expected that this material can be used as a highly efficient flocculant in future.
       
  • CaCO3 mineralization in polymer composites with cellulose nanocrystals
           providing a chiral nematic mesomorphic structure
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Yukiko Nakao, Kazuki Sugimura, Yoshiyuki Nishio CaCO3 mineralization was carried out using cellulose nanocrystal (CNC)/polymer composites wherein a chiral nematic structure of CNC assembly was immobilized in advance via a polymerization process of the precursory aqueous CNC/vinyl monomer lyotropics (7–11 wt% CNC in feed). Two series of polymer composites were prepared: CNC/poly(2-hydroxyethyl methacrylate) (PHEMA) and CNC/poly(2-hydroxyethyl methacrylate-co-acrylic acid) (P(HEMA-co-AA), HEMA:AA = 95:5–70:30 in mol). The mineralization was allowed to proceed solely by soaking the composite films in a salt solution containing Ca2+ and HCO3− under a low-basic condition (pH ≤ 9). Polymorphism of CaCO3 deposited inside the films was examined by X-ray diffractometry as a function of the soaking time (1–5 day) and also of the matrix composition. In the CNC/PHEMA series, the polymorphic form changed from amorphous calcium carbonate (ACC) (1-day soaking) to metastable crystalline vaterite (3-day soaking) and then to a mixture of vaterite and aragonite (5-day soaking). In the mineralization of the CNC/P(HEMA-co-AA) series, the formation of stable calcite was prominent besides minor appearance of vaterite. It was deduced that the mesofiller CNC and the AA unit in the vinyl polymer, both bearing an anionic group (-SO3− or -COO−), contributed to capturing Ca2+ to facilitate the CaCO3 deposition in the swollen film matrix. The pre-invested chiral nematic organization was kept in any of the mineralized films (dried); however, the helical pitch was appreciably reduced relative to that observed before the mineralization, attributable to the increase of ionic strength in the CNCs' surroundings accompanied by the wet process. Thermogravimetry showed that the mineralization definitely improved the thermal performance (heat/flame resistance) of the mesomorphic order-retaining CNC/polymer composites.Graphical abstractUnlabelled Image
       
  • Electrospun lignin-based composite nanofiber membrane as high-performance
           absorbent for water purification
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Wei Zhang, Pei Yang, Xinghui Li, Ziqi Zhu, Minzhi Chen, Xiaoyan Zhou An alkali lignin/poly (vinyl alcohol) (lignin/PVA) composite nanofiber membrane was fabricated by electrospinning and tested as an adsorbent for efficient Safranine T (ST) adsorption. Effect of lignin/PVA ratios on the morphology and chemical properties of the prepared composite membranes were studied. The influence of initial dye pH, time and temperature on the adsorption performance of composite membranes were investigated, and further evaluated the desorption and recycling behavior. The results showed that strong intermolecular hydrogen bonds were formed between the hydroxyl groups of PVA and lignin. The diameter of fiber displayed decreasing tendency to the increase in lignin content and the carbonization process. The excellent bead-free membranes were produced with the lignin content as high as 50 wt%. Further study found that the adsorption capacity increased with increasing the initial dye pH and temperature. The results of adsorption indicated that the absorption behavior of composite membranes was better consistent with the Langmuir isotherm and pseudo-second-order kinetic models. The adsorbent exhibited the excellent desorption behavior with an optimal desorption time of 4 h and constant recycling performance. Overall, these results indicate that lignin/PVA composite nanofiber membrane can be applied as a cost-efficient absorbent for removal of dyes from wastewater.
       
  • Adsorption behavior of heavy metal ions from aqueous solution onto
           composite dextran-chitosan macromolecule resin adsorbent
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Yang Liu, Lishuang Hu, Bo Tan, Jingru Li, Xiaohui Gao, Yaning He, Xifeng Du, Wei Zhang, Weili Wang Dextran-chitosan (DC) macromolecule resin was synthesized by ultrasonic heating and applied to adsorb various heavy metal ions (Cu2+, Co2+, Ni2+, Pb2+, Cd2+). The morphology and structure of the samples were characterized by various testing methods. The effects of five factors on the adsorption properties were studied. The adsorption kinetics, thermodynamics and isotherm models were discussed theoretically. The results show that the adsorption of heavy metal ions by DC resin is a spontaneous single molecule chemical adsorption, and the adsorption capacities of DC resin for Cu2+, Co2+, Ni2+, Pb2+ and Cd2+ were 342 mg g−1, 232 mg g−1, 184 mg g−1, 395 mg g−1, and 269 mg g−1, respectively at 20 °C, pH = 7 and adsorbent dose is 0.01 g. In addition, DC resin adsorbent has good reusability.
       
  • The structure and properties of granular cold-water-soluble starch by a
           NaOH/urea aqueous solution
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Hui Chen, Liwei Chen, Xugang Dang, Zhihua Shan, Rui Dai, Yajuan Wang The NaOH/urea treatment of starch results in granular cold-water-soluble starch (GCWSS). The research indicated that the optimized condition for this treatment was aqueous solution of 14% w/v NaOH and 12% w/v urea (all dosages based on starch weight) at ambient temperature (25 °C) for 10 min with stirring. The aqueous solution was then treated a water-extraction and alcohol-precipitation method. The solid sample was dried in an oven at 60 °C. The GCWSS displayed a cold-water solubility of ~90%. The GCWSS had lower amylose content. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction also indicated that it was an amorphous solid with a V-type pattern (single-helix). The NaOH/urea solution could destroy the inter and intra hydrogen bonding of starch thereby decreasing glass transition temperature, and improve the cold water solubility of native starch.
       
  • Facile synthesis of bentonite/biopolymer composites as low-cost carriers
           
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Mostafa R. Abukhadra, Nermen M. Refay, Ahmed M. El-Sherbeeny, Almetwally M. Mostafa, Mohammed A. Elmeligy Two types of bentonite/biopolymer composites (bentonite/chitosan (BE/CH) and bentonite/Co-Poly 2-hydroxyethyl methacrylate-methyl methacrylate (BE/HEMA-MMA)) were synthesized after modification of bentonite by an organic surfactant (BE/CTAB). The products were characterized as low-cost carriers for the 5-fluorouracil drug of high loading properties and controlled releasing behavior. The experimental loading results revealed the suitability of BE, BE/CTAB, BE/CH and BE/HEMA-MMA to load 114 mg/g, 230 mg/g, 273 mg/g, and 310 mg/g, respectively. The loading behaviors of BE/CTAB, BE/CH, and BE/HEMA-MMA are of excellent fitting with the Langmuir model. The adsorption energies and the thermodynamic studies revealed a physisorption mechanism (coulombic attractive forces) for the drug molecules. The thermodynamic parameters reflected spontaneous loading reactions of endothermic nature. The releasing profile showed significant enhancement with the formation of bentonite/biopolymer composites to extend for 160 h without attending the complete release either in the intestinal fluid (pH 7.4) or the gastric fluid (pH 1.2) with a preference for BE/HEMA-MMA composite. The inspected pharmacokinetics reflected erosion mechanism for the releasing of 5FU from BE/HEMA-MMA and the releasing properties of it from BE/CTAB and BE/CH controlled by a combination of erosion and diffusion mechanisms.
       
  • Ozonation of cassava starch to produce biodegradable films
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Carla I.A. La Fuente, Andressa Tamyris de Souza, Carmen C. Tadini, Pedro Esteves Duarte Augusto In this study, biodegradable films were produced from cassava starch modified by ozone at different levels. The films were produced by casting technique using native and ozonated cassava starch, glycerol as the plasticizer, and water as the solvent. Films were characterized in term of their mechanical, barrier and functional properties, morphology, crystallinity, colour, and opacity. The morphology of the ozonated films was more homogeneous in comparison to the films produced with the non-modified starch and enhanced properties were achieved. Films produced with ozonated cassava starch presented higher tensile strength, Young's modulus and lower elongation. The water vapour permeation and the oxygen permeation were increased by increasing the ozonation time. Moreover, ozone processing resulted in films with a more hydrophilic surface and lower solubility after 24 h. Possible explanations and applications were discussed. In conclusion, the ozone processing showed to be a good alternative for starch based packaging production.
       
  • Novel hyaluronic acid-tyrosine/collagen-based injectable hydrogels as soft
           filler for tissue engineering
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Yannan Liu, Daidi Fan In this study, we fabricated multifunctionalized hydrogel scaffolds based on hyaluronic acid (HA)-tyrosine and human-like collagen (HLC) by crosslinking with 1, 4-butanedioldiglycidyl ether (BDDE) for soft tissue fillers. The physicochemical of HA-tyrosine/BDDE (HTB) and various proportions of HA-tyrosine/BDDE/HLC (HTBH) hydrogels were characterized by swelling ratio, mechanical strength, morphology and thermal stability. The results demonstrated various HTBH hydrogels had superior performance in mechanical properties than HTB hydrogels. The biodegradation in vitro results demonstrated the degradation of HTBH hydrogels were slower than HTB hydrogels, and residual masses of HTBH hydrogels varied with different proportions of HA-tyrosine and HLC in the presence of the combination of HAse/collagenase I. The cell counting kit-8 (CCK-8), Hoechst/PI staining and cell adhesion of various HTBH hydrogels showed less cytotoxic and superior fibroblast attachment than those of HTB hydrogels. Moreover, subcutaneous injections of HTBH hydrogels containing high proportions of HLC in mice and rabbits all exhibit better biocompatibility and anti-biodegradation compared to HTB hydrogels after 1, 4, 8, 12 and 16 weeks. Hematoxylin-eosin staining (H&E), immunohistochemical and transmission electron microscope (TEM) analysis results indicated HTBH hydrogels had less intense inflammatory responses with increase proportion of HLC. Taken together, HTBH hydrogels had great potential application as ideal soft tissue fillers with excellent mechanical properties, biological stability and biocompatibility.
       
  • Structure elucidation and anti-tumor activity in vivo of a polysaccharide
           from spores of Ganoderma lucidum (Fr.) Karst
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Youli Fu, Lei Shi, Kan Ding To explore new anti-tumor constituents in the fungi, a water-soluble polysaccharide, WGLP was obtained from spores of Ganoderma lucidum (Fr.) Karst. The average molecular weight of this polysaccharide was estimated to be 1.5 × 104 Da. Monosaccharide composition analysis indicated that it was composed solely of glucose. From methylation analysis, 1H and 13C NMR spectroscopy, and periodate oxidation and Smith degradation, it could be concluded that WGLP contained β-d-glucose residue exclusively, with an average repeating unit of hexasaccharide, having a backbone consisting of (1 → 3)-β-d-glucopyranosyl residues, to which the side chain consisting of terminal and (1 → 6)-β-d-glucopyranosyl residue is attached at position O-6 of the branching residues. Anti-tumor activity assays in vivo showed that WGLP could significantly inhibit the S180 tumor growth in the mice. Furthermore, no drug-related toxic reactions were observed. It was suggested that WGLP might be a potential anti-tumor agent used in the clinic.Graphical abstractUnlabelled Image
       
  • The versatile O-methyltransferase LrOMT catalyzes multiple O-methylation
           reactions in amaryllidaceae alkaloids biosynthesis
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Wei Li, Chong Qiao, Jing Pang, Guolin Zhang, Yinggang Luo Amaryllidaceae alkaloids are unique benzylphenethylamine derivatives that comprise of more than 600 members with a huge chemical diversity. Most of them showed interesting bioactivities, for instance, galanthamine (GAL) is clinically used for Alzheimer's disease treatment. All Amaryllidaceae alkaloids had been thought to be derived from 4′-O-methylnorbelladine originated from norbelladine catalyzed by norbelladine 4′-O-methyltransferase (N4OMT). Herein we mined the transcriptome datasets of Lycoris radiata, a GAL-producing plant. LrOMT was cloned, overexpressed in Escherichia coli, and purified to homogeneity. Bioinformatics analysis and enzymatic activity assays revealed that LrOMT is an S-adenosylmethionine-dependent Class I OMT. LrOMT exhibited both para- and meta-O-methylation activities toward norbelladine to give 4′- and 3′-O-methylnorbelladine. Twenty-four analogues, including the proposed biosynthetic intermediates, were introduced to investigate the substrate scope of LrOMT and it showed that the aromatic substrates should have two vicinal hydroxyl groups. The LrOMT-catalyzed O-methylation preference is dependent on the properties of the binding group of the substrates. The transcription levels of LrOMT were positively associated with the accumulation of the Amaryllidaceae alkaloids and the biosynthetic intermediates in L. radiata. The present work revealed that LrOMT catalyzes multiple O-methylation reactions and its characterization will be helpful to uncover novel biosynthetic genes for Amaryllidaceae alkaloids biosynthesis.Graphical abstractUnlabelled Image
       
  • Characterization of DNA binding and ligand binding properties of the TetR
           family protein involved in regulation of dsz operon in Gordonia sp.
           IITR100
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Pooja Murarka, Preeti Srivastava Gordonia sp. IITR100 is a biodesulfurizing bacterium which can metabolize dibenzothiophene (DBT) to 2 hydroxybiphenyl in four steps via the 4S pathway. The genes involved in the metabolism are present in the form of an operon, dszABC, which gets activated by a TetR family protein. Here, we report the detailed characterization of the DNA binding and ligand binding property of the TetR family protein. The protein was found to be conserved across other desulfurizing organisms. The protein was purified and was found to exist as dimer. The presence of ligand binding site was identified by docking studies and the structural changes in the protein upon ligand binding were determined by CD spectroscopy and tryptophan fluorescence. Further, it was determined that this protein binds to an imperfect palindromic DNA sequence present in the dsz promoter DNA. Binding to the DNA also changes conformation of the protein.
       
  • Effect of precipitation solvent on some biological activities of
           polysaccharides from Pinus halepensis Mill. seeds
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Amina Abbou, Nabil Kadri, Nadjet Debbache, Sofiane Dairi, Hocine Remini, Farid Dahmoune, Farida Berkani, Khadidja Adel, Amine Belbahi, Khodir Madani This study was designed to evaluate, for the first time, the effect of the precipitation solvent (Acetone, Ethanol, and Propanol) on the antioxidant, anti-inflammatory and anticoagulant activities of the polysaccharides extract from Aleppo pine seeds. The antioxidant activity was evaluated with different tests (ABTS, DPPH, metal chelation, ferric reducing power, antiperoxidation and ORAC tests), the anti-inflammatory activity was assessed with three tests (denaturation protein inhibition, antiproteinase and anti-hemolytic tests). Finally, the anticoagulant activity was tested by endogenous and exogenous ways. The three extracts (AP: acetone polysaccharides extract, EP: ethanol polysaccharides extract and PP: propanol polysaccharides extract) have exhibited a very interesting activities but with different degrees. The AP extract was most effective in almost all antioxidant activities (antiradical ABTS and DPPH, metal chelation, reducing power and ORAC), in two in vitro anti-inflammatory and the anticoagulant activities. However, for the lipid antiperoxidation activity, it was the PP extract that gave better activity. The best antiproteinase activity was expressed by the EP extract. These results indicate that polysaccharides of Aleppo pine seed may be considered as a source of bioactive polysaccharides and the precipitation solvent of the polysaccharides has a major effect on the intensity of the bioactivity of these polysaccharides.
       
  • Fabrication of lightweight and reusable salicylaldehyde functionalized
           chitosan as adsorbent for dye removal and its mechanism
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Nira Parshi, Dipika Pan, Vishal Dhavle, Biswajit Jana, Santu Maity, Jhuma Ganguly Bio-resources have a very significant role in current research approach for the synthesis of benign functionalized biological macromolecules for their stable structural integrity and inherent nature-inspired potentialities. Here, chitosan is used as a core moiety for designing of a porous adsorbent after the attachment of salicylaldehyde to remove the toxic dyes. Salicylaldehyde linked chitosan, with excellent surface porosity, lightweight, non-glucose and low-cost feature, makes it as an efficient adsorbent. The dye loaded material is very easy to remove from the top of the water as it is suspended on water. The physico-chemical characterizations are done by FTIR, rheology, SEM and swelling study. The removal efficiency is 98% and 99% for Crystal Violet and Rose Bengal from water respectively. The thorough adsorption with mechanistic approach shows the Freundlich model as an appropriate one and follows closely pseudo-second-order kinetics model. Thermodynamic study reveals the endothermic nature of the process. Moreover, the reusability of Salicylaldehyde linked Chitosan shows its persistence with the same amount and concentration of dyes in water up to three consecutive cycles. So, the chitosan based macromolecules can be a sustainable candidate in the current scenario for the removal of dyes without the dislocation of the water container.Graphical abstractUnlabelled Image
       
  • How to calculate starch lamellar features with improved accuracy by small
           angle X-ray scattering
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Li Lin, Chengdeng Chi, Chunhua Wu Starch lamellar structures unraveled by small angle X-ray scattering (SAXS) have been critically correlated with its functionalities. However, the lamellar features calculated by the classical linear correlation function based on SAXS data are not well convincingly analyzed, because the thickness of amorphous lamellae calculated by previous studies is smaller than the smallest detectable size extrapolated from the selected data. The main reason causes this unconvincing result is the unsuitable data used. Appropriate data are selected in this study for better portraying the linear correlation function profile and then suitable principles are proposed to convincingly analyze starch lamellar features. For verifying the validity of selected data and calculated results, two criterions are established, i.e., (i) the thickness of amorphous lamellae evaluated from the correlation profiles should be larger than the smallest detectable size extrapolated from the selected data according to the Woolf-Bragg's equation and (ii) the value of the thickness of semi-crystalline lamellae calculated from the linear correlation function profile should close to that obtained from the original SAXS curve. Accordingly, the data of 0.10–2.75 nm−1 are optionally selected for calculating starch lamellar parameters. The results of this study provide a promising pathway to unravel starch lamellar features with improved accuracy.
       
  • Tetrastigma hemsleyanum tubers polysaccharide ameliorates LPS-induced
           inflammation in macrophages and Caenorhabditis elegans
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Qiang Chu, Ruoyi Jia, Meng Chen, Yonglu Li, Xin Yu, Yaxuan Wang, Wen Chen, Xiang Ye, Yangyang Liu, Yong Jiang, Xiaodong Zheng Tetrastigma hemsleyanum Diels et Gilg, a rare herbal plant native to China, possesses high medicinal value. More researches have focused on the flavones in the tubers of Tetrastigma hemsleyanum whereas polysaccharides attract few attentions. In this study, a purified polysaccharide (TTP-1) with the average molecular weights of 478.33 kDa was extracted from Tetrastigma hemsleyanum and conducted multiple analysis to identify its structural information. In vitro, TTP-1 could suppress the inflammation, cytotoxicity, genotoxicity, mitochondrial dysfunction and oxidative damage induced by LPS in RAW264.7 cells. Meanwhile, TTP-1 could attenuate inflammation via COX-2, iNOS, MAPKs pathways and ameliorate oxidative damage through Nrf2-Keap1, Sirt1-FoxO1 pathways in RAW264.7 cells. In vivo, the inflammation induced by LPS triggered the suppression of survival ratio and growing development, as well as the restrain of athletic ability in Caenorhabditis elegans. The treatment of TTP-1 reversed the situation induced by LPS. In a word, TTP-1 could ameliorate LPS-induced inflammation both in vitro and in vivo.
       
  • Central composite designed formulation, characterization and in vitro
           cytotoxic effect of erlotinib loaded chitosan nanoparticulate system
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Parijat Pandey, Dinesh Kumar Chellappan, Murtaza M. Tambuwala, Hamid A. Bakshi, Kamal Dua, Harish Dureja The most common cause of deaths due to cancers nowadays is lung cancer. The objective of this study was to prepare erlotinib loaded chitosan nanoparticles for their anticancer potential. To study the effect of formulation variables on prepared nanoparticles using central composite design. Erlotinib loaded chitosan nanoparticles were prepared by ionic gelation method using probe sonication technique. It was found that batch NP-7 has a maximum loading capacity and entrapment efficiency with a particle size (138.5 nm) which is ideal for targeting solid tumors. Analysis of variance was applied to the particle size, entrapment efficiency and percent cumulative drug release to study the fitting and the significance of the model. The batch NP-7 showed 91.57% and 39.78% drug release after 24 h in 0.1 N hydrochloric acid and Phosphate Buffer (PB) pH 6.8, respectively. The IC50 value of NP-7 evaluated on A549 Lung cancer cells was found to be 6.36 μM. The XRD of NP-7 displayed the existence of erlotinib in the amorphous pattern. The optimized batch released erlotinib slowly in comparison to the marketed tablet formulation. Erlotinib loaded chitosan nanoparticles were prepared successfully using sonication technique with suitable particle size, entrapment efficiency and drug release. The formulated nanoparticles can be utilized for the treatment of lung cancer.
       
  • Natural compound safranal driven inhibition and dis-aggregation of
           α-synuclein fibrils
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Shreyada S. Save, Kavitha Rachineni, Ramakrishna V. Hosur, Sinjan Choudhary Self-assembly of α-synuclein (α-Syn) is linked with a variety of neurodegenerative diseases collectively called as α-synucleiopathies. Therefore, discovering suitable inhibitors for this self-association process of α-Syn is a subject of intense research. In this background, we have demonstrated here that the natural compound, Safranal, delays/inhibits α-Syn fibrillation/aggregation, and we have also characterized its mode of action. The α-Syn fibrillation/aggregation kinetics studies in combination with TEM studies demonstrated that Safranal effectively inhibits α-Syn fibrillation/aggregation. NMR studies revealed that Safranal binds with α-Syn and stabilizes the monomeric protein. ANS fluorescence and CD measurements indicated that Safranal binds to the hydrophobic residues of the protein and causes delay in the formation of β-sheet rich structures which are crucial for the fibrillation to occur. The results obtained from fluorescence quenching, NMR and ANS binding assays, when analysed taking into consideration the molecular structure of Safranal provide valuable insights into the mechanism of inhibition of α-Syn fibrillation/aggregation. We infer that inhibition of α-Syn fibrillation/aggregation is primarily driven by hydrophobic interactions between Safranal and the protein. Further, Safranal is also seen to dis-aggregates pre-formed α-Syn fibrils. These findings implicate that Safranal could become a potent therapeutic intervention in Parkinson's disease and other protein aggregation related disorders.
       
  • Enhanced compatibility of starch with poly(lactic acid) and
           poly(ɛ-caprolactone) by incorporation of POSS nanoparticles: Study on
           thermal properties
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Behnaz Najaf Oshani, Seyed Mohammad Davachi, Iman Hejazi, Javad Seyfi, Hossein Ali Khonakdar, Alireza Abbaspourrad In this work, we explore the ability of polyhedral oligomeric silsesquioxane (POSS) nanoparticles to increase the compatibility of hydrophilic starch with hydrophobic poly(lactic acid) (PLA) and poly(ɛ-caprolactone) (PCL). Morphological analysis demonstrated that lower contents of POSS (0.5 and 1 wt%) enhances the compatibility of the system. However, higher inclusion of POSS results in the formation of aggregates and thus a lower level of compatibility. Transmission electron microscopy revealed that PCL acts as an intermediate between PLA and starch, and that POSS is primarily localized within the PLA and PCL phases. Based on differential scanning calorimetry, PLA's crystallinity increases from 22.9% to 31.6% upon adding a very low content of POSS (0.5 wt%). However, the PCL's crystallinity is slightly hampered due to formation of these PLA crystallites. In contrast with the crystallization behavior and based on the thermal degradation kinetics, we found the composite's thermal stability is greatly increased when moderate to high contents (3 and 5 wt%) of POSS are utilized. Dynamic mechanical analysis results also confirmed good POSS dispersion within the matrix, especially at lower contents. In conclusion, POSS serves as an efficient compatibilizer for PLA/starch/PCL systems with improved thermal properties.
       
  • Rheological, morphological, mechanical, and water-barrier properties of
           agar/gellan gum/montmorillonite clay composite films
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Hansong Lee, Balasubramanian Rukmanikrishnan, Jaewoong Lee Agar (A), gellan gum (G) and montmorillonite (M) based ternary nanocomposite films were prepared via the solution-casting method for food packaging applications. The prepared nanocomposites were investigated for the effect of MMT clay on the structure–property relationships by studying the microstructural, rheological, mechanical, thermal, ultraviolet, and water-barrier properties of AG hydrogel composites. The results indicated that the thermal stability (T5%: 119.4–174.7) and tensile strength (29.9–44 MPa) were significantly enhanced in the reinforced MMT nanoclay. The water barrier (1.9–1.7) and contact angle (56.8°–49.4°) were reduced by the incorporation of MMT clay whereas the rheological properties improved. The AGM composite solution exhibited shear thinning behavior and viscosity reduction at a high rate. Additionally, the composites exhibited significantly higher storage and loss modulus at high frequencies. The complex viscosity differed from the shear viscosity and remained higher than the shear viscosity. The nanocomposite structure, molecular interaction, and interaction in the multicomponent were investigated by FT-IR, XRD and SEM analysis. The AG and AGM nanocomposites exhibited a synergistic reinforcement effect. The results of this study might introduce a new route for enhancing the nanocomposites for sustainable materials.
       
  • Drug release and kinetic models of anticancer drug (BTZ) from a
           
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Abdelrahman I. Rezk, Francis O. Obiweluozor, Ghizlane Choukrani, Chan Hee Park, Cheol Sang Kim A pH-sensitive polymeric carrier was developed in this study for local delivery of anticancer drug bortezomib (BTZ) to cancer cells. Our strategy is based on the conjugation of BTZ to polymeric carriers containing catechol groups, which are considered to release BTZ selectively in cancer cells. In this study we used alginate-conjugated polydopamine as a building block polymer. The catechol moiety of polydopamine binds to the boronic acid group of BTZ drug and release the drug molecules in a pH-dependent method. Cancer tissue has acidic environment where BTZ dissociate from the catechol group of polydopamine to control the release of the free drug. Mathematical equation models were used to clarify the mechanism of drug release. The release profile fitted first order with correlation coefficient (R2 = 0.98), the release mechanism was studied using Korsmeyer–Peppas, Higuchi, Hixson-Crowell, and Kopcha models. We revealed the release mechanism follows non-fickian and diffusion was the dominant mechanism while small portion contributed to erosion. The pH-sensitive mechanism controls the release of BTZ in targeted cancer cells, hence developing a novel idea that is applicable in future towards other boronic acid-containing drugs to treat various kinds of health challenges.
       
  • Preparation and characterization of hybrid chitosan-silver nanoparticles
           (Chi-Ag NPs); A potential antibacterial agent
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): P. Senthilkumar, G. Yaswant, S. Kavitha, E. Chandramohan, G. Kowsalya, R. Vijay, B. Sudhagar, D.S. Ranjith Santhosh Kumar In this study, a novel ecofriendly chitosan- silver nanoparticles hybrid was developed. Biological method using leaf extract of T. portulacifolium was used as reducing agent for its synthesis and the antibacterial efficiency of these hybrid nanoparticles were evaluated against the bacteria E. coli and S. marcescens organisms. The intense peak observed around 419 nm in the UV–Vis indicates the formation of silver nanoparticles. The XRD analysis showed that the hybrid chitosan-silver nanoparticles have a polycrystalline and face-centered cubic configuration. FTIR spectrum hybrid chitosan-silver nanoparticles indicated speaks vibration of NH and OH. The EDS analysis confirmed the presence of Ag, O, C and N elements in the prepared sample. The spherical shape was obtained from TEM analysis and it indicated that with average particles around 3.24 nm to 44.80 nm. The prepared hybrid chitosan-silver nanoparticles showed significant antibacterial activities against E. coli and S. marcescens. In addition, the surface membrane damages and surface morphology of test pathogens were visualized using FESEM analysis.Graphical abstractA graphic abstract representing the key steps involved the green synthesis of hybrid Chi-Ag NPs from Talinum portulacifolium. Talinum portulacifolium leaf extracts were acting as a reducing agent to reduce the Ag ions with addition of chitosan to form hybrid Chi-Ag NPs.Unlabelled Image
       
  • Protective effects of polysaccharides on hepatic injury: A review
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Ye Yuan, Lihe Che, Chong Qi, Zhaoli Meng Chronic hepatic injury caused by hepatitis B and C virus (HBV and HCV) infection, high fat diet and alcohol intake has increased to be the critical promoter of hepatocellular carcinoma (HCC). These high risk factors set into motion a vicious cycle of hepatocyte death, inflammation and fibrosis that finally results in cirrhosis and HCC after several decades. However, the treatment options for HCC are very limited. Therefore, early treatment of liver injury may reduce the incidence and probability of HCC or delay the progression of HCC. Substantial ongoing research has focused on nontoxic biological macromolecules, mainly polysaccharides, which possess prominent efficacies on hepatoprotective activity. Based on these encouraging observations, a great deal of effort has been devoted to discovering novel polysaccharides for the development of effective therapeutics for hepatic injury. This review focuses on the protective effects of polysaccharides on liver injury, including hepatitis virus infection, nonalcoholic steatohepatitis, alcoholic liver disease and other hepatic injuries, and describes the underlying mechanisms.
       
  • Electrically conductive biomaterials based on natural polysaccharides:
           Challenges and applications in tissue engineering
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Somayeh Vandghanooni, Morteza Eskandani Since the introduction of tissue engineering (TE) concept for repair or regeneration of failed tissues/organs, this novel interdisciplinary field has progressed significantly. In this context, cells, signal molecules, and scaffolds are the key fundamental elements which required for a successful TE. Among these, scaffold as an artificial extracellular matrix (ECM) has a prominent role in cell attachment, differentiation, orientation, proliferation, and new tissue formation. Moreover, stimulants such as electric field (EF) affect different aspects of cellular performances, including polarity, wound healing, division, and differentiation. In this respect, simultaneous usage of natural polysaccharides and electrically conductive polymers can be considered as a new strategy to produce composite biomaterials as suitable scaffolds with superior physicochemical and biological properties. This review focuses on the simultaneous usage of natural polysaccharides and electrically conductive polymers for the fabrication of bio-scaffold and investigation of their performance in TE.Graphical abstractThe first up-to-date comprehensive overview of the recent developments in the fabrication and application of electrically conductive natural polysaccharides-based scaffolds in regenerative medicine is presented.Unlabelled Image
       
  • Bio-inspired synthesis of chitosan/copper oxide nanocomposite using rutin
           and their anti-proliferative activity in human lung cancer cells
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Devaraj Bharathi, R. Ranjithkumar, B. Chandarshekar, V. Bhuvaneshwari Polymer functionalized metal oxide nanocomposites are great interest due to wide range of application, especially in nanomedicine. The present study reports an eco-friendly bio-inspired synthesis of chitosan/copper oxide (CS-CuO) nanocomposite for the first time using rutin. The bio-synthesized CS-CuO nanocomposite was characterized using UV–Visible spectroscopy, FE-SEM, EDS, TEM, XRD and FTIR analyses. FE-SEM and TEM images revealed the synthesized CS-CuO nanocomposite having spherical shaped structure with an average size of 10–30 nm. EDS analysis confirmed the elements present in synthesized CS-CuO nanocomposite. FTIR studies revealed the role of rutin and chitosan for reduction, capping and synthesis of CS-CuO nanocomposite from the precursor copper salt. The XRD analysis revealed monoclinic structure of CS-CuO nanocomposite. Anti-proliferative activity of the CS-CuO nanocomposite was evaluated in human lung cancer cell line A549. Synthesized CS-CuO nanocomposite showed concentration-depended anti-proliferative activity against A549 cancer cells and their IC50 value was found to be 20 ± 0.50 μg/mL. Furthermore, synthesized nanocomposite induce apoptosis in treated A549 cancer cells assayed by AO/EtBr fluorescent staining method. In conclusion, the synthesized CS-CuO nanocomposite using rutin can be used as a potential anticancer agent in biomedical and clinical sectors.
       
  • Target DNA detection of human papilloma virus-16 E7 gene by
           capture-target-reporter sandwich on interdigitated electrode sensor
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Jing Lin, Subash C.B. Gopinath, Thangavel Lakshmipriya, Yeng Chen, Wong Ruen Yuan, Mei Yang Human papilloma virus (HPV) affects predominantly the genital area, which includes vagina, cervix, penis, vulva scrotum, rectum and anus. Among 100 types of HPV, 14 types are considered to cause the risky cancer. The gene HPV-16 E7 is responsible for the development of cancer with the infected women. Earlier identification of this gene sequence avoids the cancer progression. The targeted HPV-16 E7 sequence was sandwiched by capture and reporter sequences on the carbodiimidazole-modified interdigitated electrode (IDE) surface. Target sequence at 100 f. was paired to the capture sequence immobilized on IDE sensing surface. To this surface, different concentrations of reporter sequence with and without gold rod (GNR) were evaluated. In both cases the detections were attained 1 aM by the reporter sequence pairing and with GNR increments in current were found. This enhancement was found to be 1000 folds, considering the condition was revealed in the absence of reporter. This sandwich detection strategy of capture-target-reporter sequences for HPV-16 detection on the IDE sensing surface helps to diagnose the association of cervical cancer.
       
  • Mechanistic insight into binding interaction between chemosensory protein
           4 and volatile larval pheromones in honeybees (Apis mellifera)
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Fan Wu, Yilu Feng, Bin Han, Han Hu, Mao Feng, Lifeng Meng, Chuan Ma, Linsheng Yu, Jianke Li Honeybees communicate with members of their intra-species via pheromones. The volatile pheromones, β-ocimene and allo-ocimene, are the primary signals of larvae to beg for the care from the nurses. Of the odorant binding proteins (OBPs)/chemosensory proteins (CSPs), CSP4 has the best affinity with β-ocimene and allo-ocimene. To reveal the binding mechanism of CPS4 with them, fluorescent quenching, UV absorption spectra, circular dichroism (CD) spectra, isothermal titration calorimetry (ITC), molecular docking, molecular dynamic (MD) simulation, and site-directed mutagenesis were applied. The quenching constant Ksv decreased with temperature increase, and the interaction distance was 2.73 nm and 2.43 nm (
       
  • Preparation, characterization, and antibacterial properties of biofilms
           comprising chitosan and ε-polylysine
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Zuolong Yu, Guiwei Rao, Yunxiao Wei, Jie Yu, Sihong Wu, Yupei Fang Of late, the demand for food-packaging materials, in particular, multifunction packaging materials that are biodegradable; antibacterial; have good mechanical and barrier properties; and are edible and transparent, has increased considerably. In this study, we prepared chitosan (CS)/ε-polylysine (PL) biofilms with different CS-to-PL ratios. We studied the preparation, mechanical properties, microstructures, thermal stability, transparency, water-vapor permeability, oil permeability, and antibacterial properties of the composite CS/PL biofilms. The results demonstrate that CS/PL biofilms are mechanically strong, have good thermal stability, high transparency, low water-vapor and oil permeability, and extensive antibacterial properties that act against Escherichia coli, Bacillus subtilis, and yeast. Therefore, we therefore conclude that CS/PL biofilms are promising food-packaging materials.
       
  • Molecular characteristics of kappa-selenocarrageenan and application in
           green synthesis of silver nanoparticles
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Weiping Jin, Yiran Yu, Wenfu Hou, Guozhen Wang, Zhenzhou Zhu, Jingren He, Shuiyuan Cheng, Qingrong Huang Selenium is an essential trace element in human body, and kappa-selenocarrageenan (Se-car) is an organic source of selenium supplement. To further utilize Se-car in food packaging, biotherapy or biosensor, the molecular information of Se-car was characterized here and multi-functional Ag NPs synthesized by Se-car were fabricated. Results of GPC-MALLS, FTIR, potentiometric titration, and intrinsic viscosity showed that Se-car was polymerized by nearly 22 basic units of disaccharide. Sixty-four percentage of sulfated groups (SO42−) in carrageenan was replaced by selenium acid (SeO32−), which belonged to weak acid resulting from a gradually decrease of ζ-potential with acidity process to pH 1.0. Besides, the capacity of biosynthesis silver nanoparticles (Ag NPs) by Se-car was studied and it made a comparison with κ-carrageenan. Results exhibited that Se-car could serve as an efficient reducing and capping agent for Ag NPs fabrication (remarked as Se-car@Ag). The kapp of Se-car@Ag NPs for catalyzing 4-NP degradation was 2.14 × 10−2 s−1. Antibacterial test revealed Se-car@Ag had an ability to inhibit the growth of Escherichia coli and Staphylococcus aureus. To combine the selenium health benefit and functional metal nanoparticles, Se-car@Ag might have potential applications in multiple areas like medicine, disease diagnostic, and drug delivery.
       
  • A potent chitin-hydrolyzing enzyme from Myrothecium verrucaria affects
           
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Ravindra P. Vidhate, Amey J. Bhide, Sushama M. Gaikwad, Ashok P. Giri Chitin, a crucial structural and functional component of insects and fungi, serves as a target for pest management by utilizing novel chitinases. Here, we report the biocontrol potential of recombinant Myrothecium verrucaria endochitinase (rMvEChi) against insect pest and fungal pathogens. A complete ORF of MvEChi (1185 bp) was cloned and heterologously expressed in Escherichia coli. Structure based sequence alignment of MvEChi revealed the presence of conserved domains SXGG and DXXDXDXE specific for GH-18 family, involved in substrate binding and catalysis, respectively. rMvEChi (46.6 kDa) showed optimum pH and temperature as 7.0 and 30 °C, respectively. Furthermore, rMvEChi remained stable within the pH range of 6.0 to 8.0 and up to 40 °C. rMvEChi exhibited kcat/Km values of 129.83 × 103 [(g/L)−1 s−1] towards 4MU chitotrioside. Hydrolysis of chitooligosaccharides with various degrees of polymerization (DP) using rMvEChi indicated the release of DP2 as main end product with order of reaction as DP6 > DP5 > DP4 > DP3. Bioassay of rMvEChi against Helicoverpa armigera displayed potent anti-feedant activity and induced mortality. In vitro antifungal activity against plant pathogenic fungi (Ustilago maydis and Bipolaris sorokiniana) exhibited significant inhibition of mycelium growth. These results suggest that MvEChi has significant potential in enzyme-based pest and pathogen management.
       
  • Augmented control of drug-resistant Candida spp. via fluconazole loading
           into fungal chitosan nanoparticles
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Haddad A. El Rabey, Fahad M. Almutairi, Adel I. Alalawy, Mohammed A. Al-Duais, Mohamed I. Sakran, Nahla S. Zidan, Ahmed A. Tayel Fungal chitosan (ACT) extraction from Amylomyces rouxii, its transforming into nano-form, loading with fluconazole (Flu) and evaluation of synthesized nanoconjugates against drug-resistant (DR) Candida spp., were investigated. The produced ACT was characterized with 112.4 kDa molecular weight and 88.7% deacetylation degree. Synthesis of chitosan nanoparticles (NACT), and loading them with Flu were succeeded, using ionic gelation protocol, to generate stable Flu/NACT nanoconjugate' particles with mean size of 82 nm and zeta potential of +3.36 mV. The NACT entrapment efficiency was 78.7% and the drug loading capacity was 60.2%. Flu slowly released from NACT during the first 5 h, then release dramatically increased to the maximum (94.8%) after 12 h. The infra-red spectrum of Flu/NACT nanoconjugates confirmed the strong cross-linkage between their molecules. The antimycotic activity of NACT and Flu/NACT was proved against DR strains of C. albicans (2 strains), C. parapsilosis and C. glabrata, using qualitative and quantitative assays; Flu/NACT exhibited significant powerful activity, which was confirmed via observations with scanning microscopy. Finished cotton textiles with Flu/NACT had augmented potentiality for inhibiting challenged DR Candida spp., using in vitro assay. Accordingly, the synthesis and application of Flu/NACT nanoconjugates was astoundingly recommended for controlling DR Candida spp.
       
  • Alginate films functionalized with silver sulfadiazine-loaded [Mg-Al]
           layered double hydroxide as antimicrobial wound dressing
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Davi R. Munhoz, Marcela P. Bernardo, João O.D. Malafatti, Francys K.V. Moreira, Luiz H.C. Mattoso Alginate (ALG) is an abundant, biocompatible, regenerative, and nontoxic polysaccharide that has potential applications in tissue engineering. Silver sulfadiazine (SDZ) is a topical antibiotic used to control bacterial infection in burns. Aiming to combine the intrinsic alginate characteristics and silver sulfadiazine antimicrobial properties, hydrotalcite ([Mg-Al]-LDH) was used as a host matrix to obtain a system efficient in delivering SDZ from alginate films. SDZ was successfully intercalated in [Mg-Al]-LDH through structural reconstruction. Different solutions were prepared using sodium alginate at 10 wt%, glycerol at 10 wt% as a plasticizer and [Mg-Al]-LDH and [Mg-Al]-LDH/SDZ as fillers at 1 wt% and 5 wt%. Films were obtained by continuous casting and further characterized for their microstructural, mechanical, water barrier and antimicrobial properties. Cytotoxicity tests were also performed on fibroblasts cells. The incorporation of [Mg-Al]-LDH and [Mg-Al]-LDH/SDZ presented neither negative nor positive effects on the mechanical properties and morphology of the alginate films. Moreover, samples containing SDZ exhibited inhibitory activity against S. aureus, E. coli, and S. enterica. The addition of [Mg-Al]-LDH/SDZ even at the highest concentration did not afford a very significant cytotoxicity to the alginate-[Mg-Al]-LDH/SDZ films. These results describe a suitable approach for preparing innovative active wound dressings integrated to efficient drug delivery.
       
  • Enhanced antimycotic activity of nanoconjugates from fungal chitosan and
           Saussurea costus extract against resistant pathogenic Candida strains
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Fawzia A. Alshubaily Targeting the control of pathogenic Candida spp., especially the fungicides resistant strains from C. albicans and C. glabrata, nanoconjugates from the biopolymer (chitosan) and costus root extract (Saussurea costus) was synthesized and characterized. Chitosan was extracted from the grown mycelia of Aspergillus niger and characterized with high deacetylation degree of 91.2% and moderate molecular weight of 106.8 kDa. Synthesis of nanoconjugates from fungal chitosan/costus extract (NCt/CE) was conducted using ionic gelation technique; the resulted NCt/CE particles were characterized with mean diameter of 48 nm, positive zeta potentiality (+3.28 mV) and high stability. The infra-red spectra of synthesized nanoconjugates indicated their strong biochemical cross-linkage. The antimycotic activities, of the synthesized NCt, CE and their nanocomposite, were evaluated against standard and antibiotic-resistant strains from C. albicans and C. glabrata and revealed that the entire agents had notable antimycotic potentiality against all examined strains; the NCt/CE nanoconjugates had significantly stronger antimicrobial action. The scanning microscope imaging, of exposed resistant strains to NCt/CE, indicated their vigorous structural and morphological alterations and confirmed the antimycotic activity of the nanocomposite. NCt/CE nanoconjugates' synthesis could be exceedingly recommended as a natural, biodegradable and effectual antimycotic agent to control resistant pathogenic yeast strains.
       
  • Thermally reversible nanocellulose hydrogels synthesized via the
           furan/maleimide Diels-Alder click reaction in water
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Ricardo Klaus Kramer, Mohamed Naceur Belgacem, Antonio José Felix Carvalho, Alessandro Gandini The study deals with the synthesis of thermally reversible hydrogels from modified cellulose nanofibers via the Diels-Alder “click” reaction in an aqueous medium. “Never-dried” cellulose fibres derived from hardwood were submitted to shearing and surface TEMPO-oxidation before being modified with furfurylamine. The ensuing pendant furan moieties were reacted with a water-soluble bismaleimide via Diels-Alder coupling at 65 °C to produce a hydrogel, whose deconstruction was induced by the corresponding retro-Diels-Alder reaction carried out at 95 °C. Differential scanning calorimetry and rheological measurement were used to characterize the hydrogels. These aqueous cellulosic materials should provide original applications in such areas as strong paper-based artefacts and biocompatible gels.
       
  • Lignin prepared from different alkaline pretreated sugarcane bagasse and
           its effect on enzymatic hydrolysis
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Chao Xu, Jun Zhang, Yu Zhang, Ying Guo, Huijuan Xu, Cuiyi Liang, Zhongming Wang, Jingliang Xu Sugarcane bagasse (SCB) was pretreated by sodium hydroxide (SH), alkaline ethanol (AE) and alkaline hydrogen peroxide (AHP), and the solid residue with similar lignin content after different pretreatment was selected. Enzymatic saccharification with different substrates was performed at 2%, 10%, and 20% (w/v) solid loading. After that, the lignin from different substrate was extracted and its structure was characterized. Furthermore, the adsorption capability of isolated lignin to cellulase and its effect on enzymatic hydrolysis were studied. The results showed that, as the substrate content increased from 2% (w/v) to 20% (w/v), the glucose yield after digestion of SH, AE, and AHP pretreated SCB reduced by 41.8%, 35.4%, and 28.7%, respectively. The inhibitory effect of different prepared lignin on the digestibility of Avicel was as follows, SH pretreated lignin (SHL) > cellulase enzymatic hydrolysis lignin (CEL) > AE pretreated lignin (AEL) > AHP pretreated lignin (AHPL), which exhibited positive correlation with its non-productive adsorption capability to cellulase. Lignin samples with low negative zeta potential, high hydrophobicity and high ration of syringyl (S) to guaiacyl (G) were unfavorable for the enzymatic saccharification of cellulose.Graphical abstractUnlabelled Image
       
  • Fungal polysaccharide similar with host Dendrobium officinale
           polysaccharide: Preparation, structure characteristics and biological
           activities
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Ying-Jie Zeng, Hui-Rong Yang, Xiao-Yang Ou, Hui-Hui Su, Min-Hua Zong, Ji-Guo Yang, Weng-Yong Lou Based on the concept of endophytic fungus, if endophytic fungus can produce the same or similar product as the host plant, which will get rid of the restrictions of farmland, seasonal and pest, the active product could be sustainably obtained. In this study, an endophytic fungus polysaccharide FP showing the similar structure with the host Dendrobium officinale polysaccharide (DOP) was sustainably and cost-effectively obtained under preferred reaction conditions with different C/N ratio. The FP with high yield up to 2.77 ± 0.51 g/L showed same monosaccharide composition with DOP as well as some host-plant-associated polysaccharides in published literatures. The main chain of FP was composed by →3,6)-β-L-Man-(1→, α-D-Glc-(1→, →4)-α-D-Glc-(1→, →3,6)-β-D-Gal-(1→, and →6)-β-D-Gal-(1→, while the side chain was α-D-Glc-(1→. Meanwhile, FP was confirmed as a safe polysaccharide with good antioxidant, antiglycation and immunomodulatory activities. Furthermore, TLR2 and TLR4 were confirmed as the membrane receptors of FP on RAW264.7 cells.Graphical abstractUnlabelled Image
       
  • Insight into the binding of a synthetic nitro-flavone derivative with
           human poly (ADP-ribose) polymerase 1
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Anindita Mitra, Ria Biswas, Angshuman Bagchi, Rita Ghosh Flavones are important bioactive compounds, many of which are effective in cancer therapy for their ability to target enzymes related to DNA repair and cell proliferation. In this report, the interaction of a synthetic nitroflavone, 2,4-nitrophenylchromen-4-one (4NCO) with human poly (ADP-ribose) polymerase 1 (hPARP1) was investigated to explore its inhibitory action. Its interaction with hPARP1 was compared with that of other inhibitors through molecular docking studies. Further insight into the 4NCO-hPARP1 interaction was obtained from competitive docking and molecular dynamic simulation studies. In silico mutagenesis studies and per-residue interaction energy calculations were carried out. Quantitative Structure Activity Relationship analysis was also performed to calculate its predictive percent inhibitory activity. Our results indicated that 4NCO exhibited competitive mode of binding to hPARP1. It formed a stable interaction with the protein thereby hindering any further molecular interaction to render it inactive with a predictive inhibition of 96%. It also had good ADMET properties and showed best Autodock binding free energy values compared to other known inhibitors. 4NCO showed good hPARP1 inhibitory properties with higher bioavailability and lower probability of getting effluxed. Development of inhibitors against hPARP1 is important for cell proliferative disorders, where 4NCO can be predicted as a potential new drug.Graphical abstractUnlabelled Image
       
  • Optimization of ultrasonic-assisted extraction, characterization and
           biological activities of polysaccharides from Orchis chusua D. Don (Salep)
           
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Rehebati Nuerxiati, Aytursun Abuduwaili, Paiheerding Mutailifu, Atikan Wubulikasimu, Nigora Rustamova, Cui Jingxue, Haji Akber Aisa, Abulimiti Yili In the present study, ultrasonic-assisted extraction (UAE) of polysaccharides from Orchis chusua D. Don (salep) was optimized by response surface methodology (RSM) combined with a Box–Behnken design (BBD), the optimum conditions were determined to be: ultrasonic power of 390 W, extraction temperature of 60 °C, extraction time of 50 min and water/raw material ratio of 40 mL/g. Based on it, 48.30 ± 0.6% yield of crude polysaccharide was obtained. After purification, the chemical compositions, physicochemical and structural property was investigated based on the GC–MS, TGA, XRD, SEM and Congo red test. The results showed that USP-U and USP-N were hetero-polysaccharides, mainly composed of mannose and glucose, and the average molecular weight was 25.57 kDa and 11.64 kDa, respectively. FT-IR spectra and NMR results indicated that the presence of α-linkage glycopyranose via typical peaks. Furthermore, reducing power and antioxidant activities of both purified fractions showed a relatively high ability to scavenge free radicals. Lastly, the cytotoxicity assay showed that purified polysaccharides have no obvious cytotoxicity against RAW267.4 and L6 cells at their effective concentration and had potent anti-inflammatory activity in a concentration-dependent manner. Salep polysaccharide is expected to be developed as a new efficacy factor in the pharmaceutical and food industry.
       
  • Glycyrrhiza polysaccharide-mediated synthesis of silver nanoparticles and
           
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Zhixiang Cai, Qiaoyu Dai, Yalong Guo, Yue Wei, Min Wu, Hongbin Zhang Water-soluble glycyrrhiza polysaccharides (GPs), extracted from the root and stem of licorice, were utilized in the photo-induced synthesis of Ag nanoparticles. The size and size distribution, morphology and structures of the Ag nanoparticles were characterized by UV–vis spectroscopy (UV), X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FT-IR). The results showed that GPs played an essential role in the synthesis and stabilization of Ag particles. The prepared Ag nanoparticles varied in size and shape, dependent on the concentrations of GPs and silver nitrate. The obtained GP-stabilized Ag nanoparticles were incorporated into a biopolymeric film of curdlan as a novel source of potential antibacterial biomaterials. The resulting nanocomposite films exhibited an obvious antibacterial property with uniformly distributed Ag nanoparticles of 20–50 nm. Our results suggest that these nanocomposite films are promising templates for the design of novel antibacterial biomaterials.Graphical abstractUnlabelled Image
       
  • The chemical character of polysaccharides from processed Morindae
           officinalis and their effects on anti-liver damage
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Huilin Xu, Lulu Liu, Yanxu Chen, Hao Ma, Man Li, Wensheng Qu, Jiye Yin, Xin Zhang, Yating Gao, Junjie Shan, Yueqiu Gao The medicinal plant Morinda officinalis How and its root have long been used in traditional medicines in China. The aims of the present study were to investigate the chemical composition and liver-protective effect of crude polysaccharides (MOP-100) from the processed root of Morinda officinalis against Concanavalin A (ConA)-induced liver damage in vivo and vitro. The processed root of the herbal medicine was extracted with water at 100 °C, then precipitated with ethanol, dialyzed and freeze-dried to obtain MOP-100. The molecular weight of MOP-100 was a wide distribution. However, the processed root was extracted consecutively at 60 °C and 100 °C to obtain two crude polysaccharides MOP-60 and MOP-60-100. MOP-60 mainly contained an inulin-type fructooligosaccharide with molecular weight of 2071 Da. MOP-100 significantly inhibited the infiltration of neutrophils and macrophages into liver, improved the hepatic injury induced by ConA in mice. It stimulated the proliferation of human liver LO2 cells and decreased the cell death induced by ConA. MOP-100 also significantly inhibited the HBeAg secretion of Hep2.5.5 hepatocytes in vitro. MOP-60 and MOP-60-100 both exhibited good activity of protecting hepatocytes against ConA-induced damage in vitro. These results suggested Morinda officinalis polysaccharides exert significant hepatoprotective effect, and it might be used for treatment of immune-mediated liver disease in the future.
       
  • Chitosan coatings incorporated with propolis extract and Zataria
           multiflora Boiss oil for active packaging of chicken breast meat
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Tooraj Mehdizadeh, Ali Mojaddar Langroodi The impact of dipping in combination of propolis extract (PE) and chitosan (CH) coating enriched with Zataria multiflora essential oil (ZEO) on chemical, microbial and organoleptic properties of poultry meat was determined at 4 °C. GC–MS analysis showed that the most components of PE were Dihydrochrysin (9.69%) and b- Pinostrobin (7.41%). The results of mesophilic total viable plate counts (TVC), lactic acid bacteria (LAB), Psychotropic bacteria and Pseudomonas spp. showed detectably lower (p 
       
  • Physical and antimicrobial properties of edible films containing
           Lactococcus lactis
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Donghui Ma, Yue Jiang, Saeed Ahmed, Wen Qin, Yaowen Liu In this study, we developed edible films designed to control the growth of Staphylococcus aureus in tryptone soya agar. We analyzed three edible film-forming substrates: sodium alginate, sodium carboxymethylcellulose, and collagen. In addition, we evaluated Lactococcus lactis, which produces bacteriocin and lactic acid. Lactococcus lactis-containing edible films were constructed via tape-casting method. Optical, mechanical, and antimicrobial properties of the edible films were measured to examine the effects of Lactococcus lactis on film matrices. Further, we determined the survival of Lactococcus lactis after the film-drying process and viability of Lactococcus lactis stored for 24 days at 4 °C. Our results indicate that incorporation of Lactococcus lactis changed the physical properties of edible films. Films containing Lactococcus lactis showed reduced gloss and transparency. There are insignificant modifications were observed in terms of tensile strength and elongation at break. At 4 °C, used to represent a low-temperature environment, the growth of Staphylococcus aureus was inhibited for 7 days in edible films populated with Lactococcus lactis. The viability of Lactococcus lactis was higher in sodium alginate/sodium carboxymethylcellulose films, and was highest in films composed of sodium alginate and methylcellulose. In summary, our study provides a new method for functional food packaging.Graphical abstractUnlabelled Image
       
  • Preparation and characterization of high-strength and water resistant
           lignocelluloses based composites bonded by branched polyethylenimine (PEI)
           
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Yutao Yan, Yindan Wang, Jie Wu, Zhe Wang, Xiaoping Shen, Qingfeng Sun, Chunde Jin High-strength and water resistant lignocelluloses based composites (LC) were fabricated using branched polyethylenimine (PEI) as the main bonding agent combined with glutaraldehyde cross-linking reaction and grinding pre-treatment. Physical and mechanical properties of different composites prepared were measured and investigated. It is evident that PEI was efficient in endowing LC with high strength and excellent water resistance. The obtained physical and mechanical properties of LC were complied with the requirement of the Chinese national standard for medium-density fiberboard (MDF). Most notably, the glutaraldehyde cross-linking and grinding pre-treatment could further improve these properties. When 5% PEI and 2.5% glutaraldehyde were incorporated, together with 2-hour grinding treatment, the LC prepared exhibited the optimum modulus of rupture (MOR) 58.1 MPa, modulus of elasticity (MOE) 5077 MPa, internal bonding strength (IB) 2.14 MPa, and thickness swell (TS) 30.2%. The excellent properties obtained could be attributed to the cross-linking effect and Schiff's base addition reaction among lignocelluloses, PEI and glutaraldehyde, which were confirmed by the Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analysis. The high-strength LC prepared in this study is expected to be used as load-bearing material in structural application.
       
  • Inhibition of α-glucosidase activity and non-enzymatic glycation by
           tannic acid: Inhibitory activity and molecular mechanism
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Qian Huang, Wei-Ming Chai, Zuo-Yuan Ma, Chong Ou-Yang, Qi-Ming Wei, Shuang Song, Zheng-Rong Zou, Yi-Yuan Peng The inhibition of α-glucosidase and glycation is considered as an effective approach for the treatment of type 2 diabetes. In this study, multispectroscopic and molecular docking techniques were employed to investigate the inhibition of tannic acid on α-glucosidase and glycation. Kinetics analyses revealed that tannic acid had a significant inhibition on α-glucosidase (IC50 = 0.35 ± 0.02 μM) in a reversible and mixed competitive manner. The results acquired from fluorescence quenching and ANS-binding fluorescence methods revealed that tannic acid could bind to α-glucosidase and reduce the hydrophobic area on the surface of the enzyme. In addition, synchronous fluorescence analysis showed that tannic acid decreased the hydrophobicity of α-glucosidase and changed the conformation of the enzyme. In vitro glycation assays showed that tannic acid had strong inhibitory effects on the formation of fructosamine, dicarbonyl compounds, and fluorescent AGEs. ANS-binding fluorescence analysis showed that tannic acid could bind to BSA and reduce the hydrophobicity of BSA in glycation. Moreover, the results of molecular docking showed the interaction between tannic acid and α-glucosidase was mainly driven by hydrogen bond, electrostatic, and hydrophobic interaction. And the interaction between tannic acid and BSA was mainly driven by hydrogen bond and hydrophobic interaction.
       
  • The ubiquitin-like modification by ThiS and ThiF in Escherichia
           coli
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Xibing Xu, Tao Wang, Yulong Niu, Ke Liang, Yi Yang Escherichia coli, one of the most well-studied gram-negative bacterial species, encodes two ubiquitin-like proteins (UBLs), ThiS and MoaD. The studies on prokaryotic UBLs such as Pup, and small archaeal modifier protein have revealed the function of UBLs. However, in gram-negative bacteria, the functions of UBLs in protein modification are still poorly understood to date. Here, we report that ThiS, which has a β-grasp fold and carboxy-terminal diglycine motif similar to ubiquitin, is able to form protein conjugates in vivo and in vitro. We also constructed in vitro ThiS conjugation (thisylation) system and identified the modified lysine sites by MS/MS, this provides an essential platform for studying the UBLs thisylation system in E. coli. The modification system is dependent on lysine 83 (ATPase activity site) and cysteine 169 (zinc binding site) in ThiF and three important substrates, GroEL, PriC, FtsA, were found to be covalently modified by this system in vitro. Taken together, this study provided evidence that the protein conjugation function of β-grasp fold UBLs is conserved in the three major evolutionary lineages of life.
       
  • Molecular identification and expression analysis of natural
           resistance-associated macrophage protein (Nramp) gene from yellow catfish
           Pelteobagrus fulvidraco (Siluriformes: Bagridae)
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Ting-Ting Yang, Meng-Jie Zhang, Zhong-Jun Fan, Sen-Hao Jiang, Qiu-Ning Liu, Min Liu Natural resistance associated macrophage protein genes (Nramp) is one of the important candidate genes responsible for regulating immune response against pathogen infection. The aim of the present was to quantify expression of Nramp gene in response to pathogen infection. Here, a Nramp was identified and molecularly characterized from Pelteobagrus fulvidraco (PfNramp). The obtained 3134 bp cDNA fragment of PfNramp comprised a 5′-untranslated region (UTR) of 81 bp, a 3′-UTR of 1403 bp and an open reading frame (ORF) of 1650 bp, encoding a polypeptide of 549 amino acids that contained a typical structural features of Nramp domain (Pfam01566). BLAST analysis exhibited that PfNramp shared sequence similarity to other organisms, in particular to Ictalurus furcatus (92%), Danio rerio (82%), and Homo sapiens (77%). Phylogenetic analysis revealed that PfNramp is close to Teleostei. Real-time quantitative reverse transcription-PCR (qRT-PCR) analysis showed that PfNramp was expressed in all examined tissues, with the highest abundance in liver. The mRNA expression of PfNramp was remarkably increased at different time points after lipopolysaccharide (LPS), and polyriboinosinic polyribocytidylic acid (poly I:C) challenge. These results suggest that PfNramp is an inducible protein in the innate immune reactions of P. fulvidraco and probably in other fish species.
       
  • Geobacillin 26 - high molecular weight bacteriocin from a thermophilic
           bacterium
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Manta Vaičikauskaitė, Marija Ger, Mindaugas Valius, Andrius Maneikis, Eglė Lastauskienė, Lilija Kalėdienė, Arnoldas Kaunietis Bacteriocins are ribosomally synthesized peptides/proteins produced by bacteria. These compounds have antibacterial activity against other bacteria that are usually closely related to the producer strain. Here we describe bacteriocin geobacillin 26 from a thermophilic Gram-positive bacterium Geobacillus stearothermophilus 15. We have purified native bacteriocin, determined its amino acid sequence and heterologously expressed in Gram-negative Escherichia coli. Geobacillin 26 is a heat-labile, high molecular weight antibacterial protein belonging to class III bacteriocins. It has a narrow antibacterial spectrum against other thermophilic bacteria. Our study suggests that this bacteriocin is not a cell wall hydrolyzing enzyme as most of high molecular weight bacteriocins. In addition, geobacillin 26 has no amino acid sequence similarities to other known function proteins. No other class III bacteriocin from a thermophilic bacterium has been reported and well characterized before. Geobacillin 26 as a natural antibacterial agent has a great potential in industry where contamination with other thermophilic bacteria is unwanted. Moreover, this study may prompt to disclose more novel geobacillin 26-like antibacterial proteins, which could find their applications in food industry or medicine.
       
  • Study on the compatible interface of bamboo fiber/polylactic acid
           composites by in-situ solid phase grafting
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Wenhao Li, Xiaoyu He, Yingfeng Zuo, Shu Wang, Yiqiang Wu The in-situ reactive interfacial compatibilization and properties of polylactic acid-g-bamboo fiber (PLA-g-BF)/polylactic acid (PLA) composites, produced by blending with a three-component plasticizer, glycerol/formamide/tributyl citrate, were investigated. The PLA-g-BF/PLA composites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimeter (DSC), thermal gravimetric analyzer (TGA) and rotational rheometer, and the bending, tensile, and water resistance properties were also tested. The bending strength and elongation at break of PLA-g-BF/PLA composite reached 35.6 MPa and 5.59%, which increased by 19.3% and 30.1% relative to the ungrafted composites. The initial contact angle of the PLA-g-BF/PLA composite was 74.3°, which was larger than that of the ungrafted composite (41.2°), and the water absorption ratio reached 4.3% after 24 h, which was less than the unmodified material (6.1%). SEM results showed that PLA matrix showed smooth surfaces and the interfacial adhesion between modified BF and matrix PLA was greatly improved after grafting modification. The crystal structure results proved that the grafting treatment of BF strengthened the interfacial interactions between the filler BF and matrix PLA, and reduced the mobility of PLA molecular chain. The rotational rheometer illustrated that the initial storage modulus of PLA-g-BF/PLA composites was the largest and decreased slowly, which improved the processing properties of composites.Graphical abstractUnlabelled Image
       
  • Special issue: 12th APCCS-14th ICCC-2018-chemistry, environmental,
           biotechnology and biomedical aspects of chitin and chitosan
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): H. Tamura, T. Furuike, R. Jayakumar
       
  • Physicochemical properties and bioactivities of original and Se-enriched
           polysaccharides with different molecular weights extracted from Pleurotus
           ostreatus
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Li Wang, Peng-zhan Zhang, Jin-wen Shen, Yan-yan Qian, Miao Liu, Yuan Ruan, Xu-guang Wang, Shao-ning Zhang, Bing-ji Ma Three polysaccharides (WZP1, WZP2, WZP3) and their Se-enriched products (SeWZP1, SeWZP2 and SeWZP3) were obtained from Pleurotus ostreatus using a simple, rapid method and HNO3-Na2SeO3 method, respectively. The molecular weight distribution profiles of all samples except SeWZP2 showed double peaks. The average molecular weights (Mw) of WZP1–3 were 48.6 kDa, 20.2 kDa and 11.8 kDa, respectively, and of SeWZP1–3 were 19.6 kDa, 37.7 kDa, 14.5 kDa, respectively. The complexity of monosaccharide composition of WZP1–3 was inversely proportional to the ethanol concentration used in the ethanol precipitation process. Additionally, the results of biological activity tests indicated that α-glucosidase inhibitory activity of WZP1–3 was related to the molecular weight and the monosaccharide composition complexity. The selenized modification can improve the α-glucosidase-inhibiting, hydroxyl radical-scavenging activity of P. ostreatus polysaccharides. Therefore, by improving their bioactivities by selenization, the polysaccharides of P. ostreatus could be utilized as a natural health food supplement.Graphical abstractUnlabelled Image
       
  • pH-sensitive and specific ligand-conjugated chitosan nanogels for
           efficient drug delivery
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Lei Xing, Ya-Tong Fan, Li-Jun Shen, Chen-Xi Yang, Xiao-Ying Liu, Yan-Ni Ma, Lian-Yu Qi, Ki-Hyun Cho, Chong-Su Cho, Hu-Lin Jiang Nanogels have been recently attracted attentions because they exhibit significantly different behaviors compared with nanoparticles. Among them, chitosan (CS) nanogels have gained considerable attentions from researchers for in vivo applications due to bioactivity, biodegradability, mucoadhesiveness, and biocompatibility of CS. In this review, we have summarized the applications of CS nanogels for efficient drug delivery. Specifically, CS nanogels can be modified by pH-sensitive groups or specific ligands to obtain the corresponding functions. These functional CS nanogels have been used to deliver therapeutic agents, such as anti-cancer drugs, genes, and vaccines. By reviewing the recent research progress on CS nanogels in pharmaceutical applications, it will provide biomaterial researchers potential help for the development of CS nanogel delivery system to meet clinical needs.
       
  • Isolation, structural characterizations and bioactivities of
           exopolysaccharides produced by Bacillus licheniformis
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Zhenxiang Xu, Guoqiang Chen, Le Xue, Haibo Zhang, Jiming Wang, Haiying Xiang, Jinglong Li, Kai Zheng Extraction polysaccharide from microorganism is a research hotspot. In this work, a new type of water-soluble exopolysaccharides (EPS) was isolated from Bacillus licheniformis. Firstly, response surface methodology (RSM), based on a three-level, three-factor, was used to determine optimum conditions for EPS extraction. And RSM analysis indicated optimum condition was at the temperature of 8 °C for 10.44 h with ethanol at a concentration of 79.22% (v/v), the maximum yield of EPS was 3.07 g/mL. Secondly, EPS were seperated using DEAE-Sepharose Fast Flow column chromatography and acquired two polysaccharide fractions, BL-P1 and BL-P2. BL-P1 had larger molecular weight than BL-P2 from structural analyses, because of higher content of mannose, ribose, glucuronic acid, galactose, arabinose and fructose in BL-P2. Moreover, the characterization of BL-P1 and BL-P2 was investigated with Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy, the results indicated that EPS was mainly composed of→3)-α-d-Galp-(1→, →3,5)-α-l-Araf-(1→, →3)-β-d-Glcp-(1→, β-d-Glcp-(1 → and→4)-β-l-Fucp-(1 → 4)-β-d-Xylp-(1 → 4)-α-l-Rhap (1 → 3) -β-d-Manp-(4 → residues. In vitro antioxidant activity assay, EPS exhibited potent quenching capacities on hydroxyl and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals in a dose-dependent manner. Furthermore, BL-P2 had higher activity than BL-P1 in inhibiting α-amylase and α-glucosidase, which would have potential to be applied in nutraceutical and pharmaceutical industries.
       
  • Dynamic structural determinants underlie the neurotoxicity of the
           N-terminal tau 26-44 peptide in Alzheimer's disease and other human
           tauopathies
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Giordano Perini, Gabriele Ciasca, Eleonora Minelli, Massimiliano Papi, Valentina Palmieri, Giuseppe Maulucci, Matteo Nardini, Valentina Latina, Veronica Corsetti, Fulvio Florenzano, Pietro Calissano, Marco De Spirito, Giuseppina Amadoro The intrinsically disordered tau protein plays a pivotal role in the pathogenesis of Alzheimer's disease (AD) and other human tauopathies. Abnormal post-translational modifications of tau, such as truncation, are causally involved in the onset/development of these neurodegenerative diseases. In this context, the AD-relevant N-terminal fragment mapping between 26 and 44 amino acids of protein (tau26-44) is interesting, being endowed with potent neurotoxic effects in vitro and in vivo. However, the understanding of the mechanism(s) of tau26-44 toxicity is a challenging task because, similarly to the full-length tau, it does not have a unique 3D structure but exists as dynamic ensemble of conformations. Here we use Atomic Force Spectroscopy, Small Angle X-ray Scattering and Molecular Dynamics simulation to gather structural and functional information on the tau26-44. We highlight the presence, the type and the location of its temporary secondary structures and we unveil the occurrence of relevant transient tertiary conformations that could contribute to tau26-44 toxicity. Data are compared with those obtained on the biologically-inactive, reverse-sequence (tau44-26 peptide) which has the same mass, charge, aminoacidic composition as well as the same overall unfolded character of tau26-44.
       
  • Improved pullulan production by a mutant of Aureobasidium melanogenum
           TN3-1 from a natural honey and capsule shell preparation
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Lu Chen, Zhe Chi, Guang-Lei Liu, Si-Jia Xue, Zhi-Peng Wang, Zhong Hu, Zhen-Ming Chi Aureobasidium melanogenum TN3-1 isolated from a natural honey was a highly genome-duplicated yeast-like fungal strain and a very high pullulan producer. In this study, simultaneous removal of both duplicated AMY1 genes encoding α-amylase and duplicated PKS1 genes responsible for melanin biosynthesis in A. melanogenum TN3-1 rendered a mutant AMY-PKS-11 to transform 140.0 g/L of glucose to produce 103.50 g/L of pigment-free pullulan with molecular weight (Mw) of 3.2 × 105 g/mol. α-Amylase activity produced by the mutant AMY-PKS-11 and expression of the AMY1 genes and PKS genes in it was reduced, but expression of various genes responsible for pullulan biosynthesis in the mutant AMY-PKS-11 was up-regulated. The produced pullulan was used to make the capsule shells successfully and the prepared pullulan capsule shells had various advantages such as high strength, good oxygen barrier properties, raw materials availability, tightness, lightness and high water resistance and may be suitable for all the consumers. Therefore, the prepared capsule shells had highly potential applications in food and pharmaceutical industries.
       
  • Characterization and application of the microencapsulated carvacrol/sodium
           alginate films as food packaging materials
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Meng Cheng, Juan Wang, Rongfei Zhang, Ruiqi Kong, Wenqian Lu, Xiangyou Wang The carvacrol (CAR) was microencapsulated by β-cyclodextrin (βCD). To extend the shelf-life of white mushrooms against Trichoderma sp., the microencapsulated CAR (βCD-CARM)/sodium alginate (SA) films were prepared and characterized. The antifungal, physical, and mechanical properties of the films were investigated in this study. The results showed that the βCD-CARM with a core-to-wall ratio of 1:10 had better encapsulation efficiency and antifungal activity against Trichoderma sp., which was isolated from postharvest white mushrooms stored at 4 °C. The optimum concentration of βCD-CARM against Trichoderma sp. in vitro was 15 g/L. The water resistance, mechanical properties, light barrier property and heat aging of the film were enhanced after adding βCD-CARM. The films with 30 g/L βCD-CARM could efficiently against Trichoderma sp. The performance of βCD-CARM/SA films was confirmed to control the release of CAR for enhanced antifungal activity. Besides, the βCD-CARM/SA films increased the activities of active free-radical scavenging enzymes to alleviate oxidative damage and delay senescence of the postharvest white mushrooms.Graphical abstractUnlabelled Image
       
  • Synergistic effect of a novel chitosan/silica nanocomposites-based
           formulation against gray mold of table grapes and its possible mode of
           action
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Khamis Youssef, Admilton G. de Oliveira, Cesar Augusto Tischer, Ibrar Hussain, Sergio Ruffo Roberto Ecofriendly nanostructured materials have been proposed as promising alternative control means to prevent plant diseases. Chitosan nanoparticles (CN), silica nanoparticles (SN) and chitosan-silica nanocomposites (CSN) were synthesized and their morphology and structure was characterized by transmission electron microscope (TEM), scanning electron microscopy (SEM), infrared spectra (FT-IR) and Raman spectroscopy. Their antifungal efficiency against Botrytis cinerea, the causal fungus of gray mold disease of table grapes, was tested in vitro and in vivo (under artificial and natural infections). In vitro tests showed that CN, SN and CSN reduced fungal growth by 72, 76 and 100%, respectively at 1% as compared to control. Under natural infection, at the end of cold storage, CSN was the most effective treatment, and reduced the development of gray mold by 59 and 83%, for ‘Italia’ and ‘Benitaka’ grapes, respectively as compared to the water control. Results indicate that a synergistic effect of CSN against gray mold was observed. The impact of tested nanocomposites on soluble solids - TSS, titrable acidity - TA, TSS/TA, berry color, mass loss, stem browning and shattered berries was investigated. No negative effect of tested nanomaterials in term of grape quality was observed. For ‘Italia’ table grape, CN and CSN can preserve bunches from mass loss as compared to control. Also, the effect of CSN on reactive species of oxygen (ROS), ATP content and mitochondrial membrane potential (MMP) of B. cinerea spores was determined to verify its mode of action. The obtained results suggested CSN, as alternative control means, to reduce/substitute the use of fungicides to control gray mold of table grapes while maintaining grape quality.
       
  • Interaction between barley β-glucan and corn starch and its effects on
           the in vitro digestion of starch
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Hui Zhang, Zhi Li, Yanjun Tian, Zibo Song, Lianzhong Ai A β-glucan was extracted from hull-less barley (HBBG) and its effects on the solution properties and in vitro digestion of corn starch (CS) were studied. Rheological results showed that HBBG diminished the gelling ability and increased the apparent viscosity of CS solution. The critical concentration was lowered from 1.10% (CS) to 0.48% (CS/HBBG mixture), and the slow relaxation component T22 decreased from 1417.47 to 464.16 ms after the incorporation of HBBG to CS solution. In vitro digestion study indicated that HBBG significantly increased the apparent viscosity of digesta and inhibited the starch hydrolysis and glucose diffusion. The entanglement and overlap formed by HBBG and CS interaction and aggregates of HBBG itself were considered to enhance the viscosity, thus limiting the water mobility of the system, reducing the contact of digestive enzyme with starch and diffusion of glucose to the small intestinal microvilli. This study suggests that HBBG can be recognized as an important ingredient in starch food to reduce postprandial glycemic responses.
       
  • Slow degrading hyaluronic acid hydrogel reinforced with cationized
           graphene nanosheets
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Rahul Patil, Vrushti Kansara, Debes Ray, Vinod K. Aswal, Prafulla K. Jha, Pratap Bahadur, Sanjay Tiwari Graphene possesses a large surface area and offers high loading capacity for aromatic compounds. However, the load is quickly released in the absence of rate limiting diffusion barrier. In this study, we have explored the electrostatic interaction between polyanionic hyaluronic acid (HA) and cationized reduced graphene oxide (rGO) as a means to develop a reinforced hydrogel matrix. We tested if; (i) degradation kinetics of HA matrix can be modulated in the presence of cationized nanosheets, and (ii) reinforced hydrogel can offer controlled release of paclitaxel (PLX) stacked over the sheets. Successful synthesis, cationization and drug loading on graphene sheets were demonstrated using Raman and FT-IR spectroscopy. Reinforcement was confirmed through electron microscopy, neutron scattering and texture profile analyses. While incorporation of sheets enhanced the resistance of HA hydrogel against enzymatic digestion, a significant improvement in the biocompatibility of cationized rGO was obtained through this association. Reinforced gel offered sustained release of PLX up to 104 h which can further be extended by tuning its architecture.Graphical abstractUnlabelled Image
       
  • Development of chitin cross-linked enzyme aggregates of L-methioninase for
           upgraded activity, permanence and application as efficient therapeutic
           formulations
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Suganya Kannan, Murugan Marudhamuthu In this study, L-methioninase (METs) was precipitated from Pseudomonas putida MTCC 9782 and was cross-linked with a cross-linking agent glutaraldehyde to obtain a catalytically active insoluble enzyme. Among the various precipitants tested, ammonium sulfate displayed the highest precipitating (80%) efficiency. A double-response statistical concept, software that provides 20 different runs, was employed to assess the role of precipitant, concentration of cross-linking agent, and duration of cross linking. From the different 20 runs performed, the highest enzyme activity was observed in run 6 (88.17 U): the aggregate size was 11.57 μm, the concentration of saturated ammonium sulfate was 80% and glutaraldehyde 2 mM, and the incubation period was 12 h. R2 values of 0.9754 (enzyme activity) and 0.9203 (aggregate size) were obtained, which showed an enhanced association between the experimental and predicted values of enzyme activity. Enzyme molecules covalently cross-linked with chitin beads showed increased activities compared to free enzymes and enzymes cross-linked with glutaraldehyde. FTIR spectra confirmed the secondary structural alterations between CLEA-METs and chitin-cross-linked CLEA-METs. Thermal stability assays showed that chitin cross-linked CLEA-METs and CLEA-METs retained maximum enzyme activities of 95% and 80% at temperatures 55 °C and 60 °C, respectively. Storage stability assays showed that CLEA-METs retained 65% of their initial activity and chitin-immobilized CLEAs retained 88% of their activity. Moreover, scanning electron microscopy, transmission electron microscopy, and high content screening imaging technique revealed that chitin-immobilized CLEA-MET microspheres showed good monodispersity and mesoporous structure with the amorphous clusters of CLEA with few pores. Cytotoxicity analysis demonstrated that chitin-immobilized CLEA-MET significantly inhibited the proliferation of A549 cells up to 96.66% compared to free enzyme (72%) and CLEA-METs (76%).Graphical abstractIllustration of CLEA preparation and its therapeutic application.Unlabelled Image
       
  • New pectin-induced green fabrication of Ag@AgCl/ZnO nanocomposites for
           visible-light triggered antibacterial activity
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Ningxiang Yu, Hailong Peng, Liang Qiu, Ronghui Wang, Chengjia Jiang, Taimei Cai, Yong Sun, Yanbin Li, Hua Xiong The pectin (CEP) was used as matrix material to prepare Ag@AgCl/ZnO nanocomposites with a green method for photocatalytic antibacterial activity in visible-light. Briefly, Ag@AgCl plasmonic hybrids were prepared in the CEP macromolecule matrix with size control, which was attributed to the stability of carboxyl and hydroxyl groups on the CEP. Subsequently, an effective and green two-steps approach was explored for the fabrication of CEP-Ag@AgCl/ZnO nanocomposites with resource saving and environment friendly. Interestingly, more Ag+ was converted into metallic Ag in the CEP-Ag@AgCl/ZnO than that in the CEP-Ag@AgCl. This phenomenon was attributed that the reducibility of free hemiacetal hydroxyl groups on CEP was realized with the help of NaOH in the preparation of CEP-ZnO. In addition, the CEP chains were not obviously destroyed except for the change in the crystallinity after the preparation of the CEP-Ag@AgCl/ZnO nanocomposites, indicating that the method was non-destructive. Moreover, the pH triggered release of Zn2+ and low release of Ag+ in CEP-Ag@AgCl/ZnO nanocomposites with excellent photocatalytic antibacterial activity were confirmed in this work. The proposed green process provides a new idea for the large-scale production of antibacterial pectin-based nanocomposites in industry with a low-cost.
       
  • PVA/(ligno)nanocellulose biocomposite films. Effect of residual lignin
           content on structural, mechanical, barrier and antioxidant properties
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Eduardo Espinosa, Isabel Bascón-Villegas, Antonio Rosal, Fernando Pérez-Rodríguez, Gary Chinga-Carrasco, Alejandro Rodríguez Nanocelluloses with and without residual lignin were isolated from wheat straw. In addition, the effect of TEMPO-mediated oxidation on the production of lignin-containing nanocellulose was studied. The different nanocelluloses were used as reinforcing agent in Poly(vinyl alcohol) films. The morphology, crystallinity, surface microstructure, barrier properties, light transmittance, mechanical and antioxidant properties were evaluated. The translucency of films was reduced by the addition of nanocellulose, however, the ability to block UV-light increased from 10% for PVA to>50% using lignin-containing nanocellulose, and 30% for lignin-free samples. The mechanical properties increased considerably, however, for loads higher than 5% a negative trend was observed presumptively due to a clustering of nanocellulose components in PVA matrix. The barrier properties of the films were improved with the use of nanocellulose, especially at small amounts (1–3%). The antioxidant capacity of films was increased up to 10% using lignin-containing nanocellulose compared to 4.7% using PVA.
       
  • Reinforced lignin-phenol-glyoxal (LPG) wood adhesives from coconut husk
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Nurul Azila Aziz, Ahmad Faiz Abdul Latip, Leo Choe Peng, Nur Hanis Abd Latif, Nicolas Brosse, Rokiah Hashim, M. Hazwan Hussin Lignin was extracted from coconut husk via alkaline pulping, either Kraft or soda. The isolated lignin samples were classified as hydroxy-benzaldehyde, vanillin, and syringaldehyde type according to Fourier-transform Infrared Spectroscopy, 1H and 13C Nuclear Magnetic Resonance (NMR) spectra. Soda lignin (SL) showed higher thermal stability and glass transition temperature (Tg) than Kraft lignin (KL) as proven by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. The soda-lignin-phenol-glyoxal (SLPG) resins with the optimum percentage of lignin substitution at 30% showed improved solid content and gel time in comparison to 30% of Kraft-lignin-phenol-glyoxal (KLPG) and phenol-glyoxal (PG) resin. The good mechanical properties in SLPG is due to the higher amount of molecular weight as well as higher phenolic and G-type unit in lignin that improve the properties of 30% SLPG adhesive. Moreover, the addition of layered double hydroxides (LDH) as reinforced filler up to 15%–30% SLPG adhesive blend shows a great performance (especially mechanical properties) as compared to 30% SLPG adhesive alone.
       
  • Effect of sodium alginate and carboxymethyl cellulose edible coating with
           epigallocatechin gallate on quality and shelf life of fresh pork
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Chengcheng Ruan, Yumeng Zhang, Yue Sun, Xueling Gao, Guoyuan Xiong, Jin Liang The active edible coatings were prepared by incorporating epigallocatechin gallate (EGCG) into sodium alginate (SA) and carboxymethyl cellulose (CMC) to investigate the effect of SA-CMC-EGCG coatings on quality and shelf life of fresh pork stored at 4 ± 1 °C for 7 days. The antioxidant effects against lipid oxidation (TBARS), total volatile basic nitrogen (TVB-N) and antimicrobial activity against total viable counts (TVC) were analyzed. Besides, the changes in color parameters and sensory attributes of all pork samples were evaluated. The results showed that fresh pork coated with SA-CMC edible coating with EGCG had a significant inhibitory effect on its microbial growth (P 
       
  • Development a smart edible nanocomposite based on mucilage of Melissa
           officinalis seed/montmorillonite (MMT)/curcumin
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): H. Rostami, A. Aliakbar Esfahani The aim of the present study was, first to fabricate Melissa officinalis seed gum (MOSG)-based films incorporated with montmorillonite (MMT) at various concentrations and subsequently, evaluate of the physicochemical properties of the developed films. Afterward, the anti-bacterial and anti-mold activities of the developed nanocomposites were assessed. Finally, curcumin was incorporated into formulation of the fabricated film at optimal condition to sense pH changes. Incorporating MMT nanoparticles into MOSG-based films could reduce the thickness, water solubility and moisture content of the samples. Tensile strength (TS) and elongation at break (EB) values significantly increased with increase of MMT concentration. The nanoparticle addition specifically at higher levels resulted in increase of agglomeration. Neither anti-mold and nor anti-microbial activity were observed for the tested nanocomposites. The films containing curcumin had good antibacterial and anti-mold activities and can be used as smart package due to their ability to sense the pH change.
       
  • Core-shell-corona chitosan-based micelles for tumor intracellular
           pH-triggered drug delivery: Improving performance by grafting polycation
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Pengwei Xie, Peng Liu Core-shell-corona chitosan-based micelles were designed for the tumor intracellular pH-triggered doxorubicin (DOX) delivery, via a facile in-situ micellization in an aqueous solution of DOX and polyethylene glycol (PEG) and poly(2-(diisopropylamino) ethyl methacrylate) (PDPA) dual-modified chitosan (PEG-g-CS-g-PDPA). The effect of the PDPA modification on the diameter, drug loading-capacity (DLC) and pH-triggered drug release was investigated for the three different polymerization degrees of PDPA (25, 32, and 42) with a similar modification degree of ~22%. The optimized ones, the core-shell-corona DOX/PEG-g-CS-g-PDPA32 micelles possessed a mean hydrodynamic diameter (Dh) of 211 nm and DLC of 54%, showing an excellent pH-triggered drug release with negligible premature drug leakage in 60 h. Such results indicated that grafting polycation could efficiently improve the performance of the chitosan-based drug delivery system (DDS) for tumor chemotherapy.
       
  • Chitosan production from Paecilomyces saturatus using three
           monosaccharides via mixture design
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Chen-Hsueh Lin, Po-Hsin Wang, Ten-Chin Wen In this study, we demonstrate that chitosan is produced from Paecilomyces saturatus fungi using ternary monosaccharide carbon sources liquid cultivation via mixture design strategy. Sixteen experiments were carried out to obtain regression equations of fungal dry mycelial biomass (W), chitosan ratio (R), and deacetylation degree (DD) for plotting contour lines. Contour lines reveal that the maximum W, R, and DD can be simultaneously obtained in cultivated media containing 20% glucose, 60% fructose and 20% mannitol rather than pure monosaccharide cultivation. Three additional confirmation experiments based on the maximum FuCS deacetylation degree had been performed to confirm to be 92.3% via Fourier-transform infrared spectra. Accordingly, FuCS possessed much better anti-microbial activity on E. coli than commercial chitosan (CrCS). Meanwhile, X-ray diffraction results confirmed that FuCS possessed both α and γ crystalline peaks while CrCS possessed only α crystalline peak, being collaborated with thermogravimetric analysis results. The superior FuCS was obtained by using ternary monosaccharides system in fungal culture via mixture design for the first time. This study provides a new approach to produce chitosan from fungal cultivation by using the mixture design strategy.
       
  • Sargassum muticum extract based on alginate biopolymer as a new efficient
           biological corrosion inhibitor for carbon steel in hydrochloric acid
           pickling environment: Gravimetric, electrochemical and surface studies
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): I. Nadi, Z. Belattmania, B. Sabour, A. Reani, A. Sahibed-dine, C. Jama, F. Bentiss The inhibition effect of the invasive brown seaweed Sargassum muticum extract (ESM), harvested from the Atlantic coast of Morocco, against the corrosion of carbon steel (CS) in 1 M HCl medium was studied for the first time using gravimetric, electrochemical and surface techniques. The methanolic crude extract of Sargassum muticum (ESM) is rich in alginate biopolymer. The evaluation corrosion tests showed that this algal extract acts as a good mixed corrosion inhibitor for CS substrate in 1 M HCl since inhibition efficiency of 97% was reached with 1 g/L of ESM at 303 K. AC impedance findings showed that the seaweed extract adding in the corrosive electrolyte increases the polarization resistance and conversely decreases the charge capacitance at the interface. Adsorption of ESM on the substrate surface followed the Langmuir adsorption isotherm. X-ray photoelectron spectroscopy analyses (XPS) demonstrated that the corrosion inhibition mechanism of CS substrate in 1 M HCl environment by the investigated algal extract is typical of the chemisorption process and the protective barrier is mainly formed by the adsorbed biological macromolecules.
       
  • Development of a conserved chimeric vaccine based on helper T-cell and CTL
           epitopes for induction of strong immune response against Schistosoma
           mansoni using immunoinformatics approaches
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Abolfazl Rahmani, Masoud Baee, Maryam Rostamtabar, Ahmad Karkhah, Solmaz Alizadeh, Mehdi Tourani, Hamid Reza Nouri Currently, three recombinant antigens based vaccines are under clinical trials against Schistosomiasis, but there is no vaccine available for prophylaxis or therapeutic. This study was conducted to construct a multi-epitope based vaccine against Schistosoma mansoni via utilizing Sm14, Sm21.7, Sm23, Sm29, Smp80, Sm-CB and SM-TSP-2 antigens. Helper T lymphocyte (HTL), cytotoxic T lymphocyte (CTL) and IFN-γ epitopes were predicted. Furthermore, Pan HLA DR-binding epitope was added to the vaccine. Moreover, 50S ribosomal protein L7/L12 of Mycobacterium tuberculosis as a novel TLR4 agonist was applied. The TAT peptide was added to the vaccine to augment intracellular delivery. The selected epitopes were linked together through appropriate linkers and chimeric vaccine was constructed with 617 amino acids with molecular weight of 65.43 kDa. Physico-chemical properties revealed a soluble protein with antigenic and non-allergic properties. Further analyses validated the stability of the construct that was able to interact with TLR4. Immunoinformatics analysis demonstrated the strong potential of constructed vaccine to stimulate T and B-cell mediated immune responses. In summary, obtained data indicated that the proposed vaccine can properly induce both T and B cells immune responses and could possibly be utilized for prophylactic or therapeutic aims in response to infection caused by S. mansoni.
       
  • Modulation in quality attributes of dough and starch digestibility of
           unleavened flat bread on replacing wheat flour with different minor millet
           flours
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Bharati Sharma, Hardeep Singh Gujral The dough characteristics and flat bread quality parameters were studied on replacing a part of wheat flour with different minor millets (finger, foxtail, barnyard, kodo, little, proso) in the proportion 3:1. The dietary fiber and phytic acid increased while damaged starch decreased on replacing wheat flour with millet flour. The millet flours lowered water absorption and dough stability however protein weakening, gelatinization temperature and peak viscosity during heating increased. Flat breads prepared from wheat millet composite flour displayed more shrinkage and bake loss and reduced puffing and starch retrogradation. Rapidly digestible starch and glycemic index lowered while slowly digestible and resistant starch increased significantly (p 
       
  • Natural protein-based hydrogels with high strength and rapid self-recovery
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Zhao Liu, Ziqing Tang, Lin Zhu, Shaoping Lu, Feng Chen, Cheng Tang, Huan Sun, Jia Yang, Gang Qin, Qiang Chen Natural protein hydrogels are considered as the promising candidates for biomaterials. However, natural protein hydrogels often exhibit poor mechanical properties. Herein, using bovine serum albumin (BSA) as natural protein model, a new kind of D/C-hybrid DN gels, consisting of tetrakis(hydroxymethyl)phosphonium chloride (THPC) cross-linked BSA (THPC-BSA) as dynamic covalent bond cross-linked first network and covalently cross-linked polyacrylamide (PAAm) as second network, were successfully synthesized by a facile method. Different from fully chemical DN gels without recovery, the optimized THPC-BSA/PAAm D/C-hybrid DN gel not only demonstrated excellent tensile properties, but also displayed extremely fast self-recovery property and fatigue resistance. More importantly, various natural proteins could be also used to prepare natural protein-based D/C-hybrid DN gels, and all of them showed improved mechanical properties and fast self-recovery properties. The results indicate our new strategy to fabricate recoverable natural protein-based D/C-hybrid DN gels is general. We hope our new strategy as well as our natural protein-based D/C-hybrid DN gels will provide a new avenue to prepare and study high performance natural protein hydrogels.
       
  • Synthesis of chitosan cross-linked 3D network-structured hydrogel for
           methylene blue removal
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Wei Wang, Haoyu Bai, Yunliang Zhao, Shichang Kang, Hao Yi, Tingting Zhang, Shaoxian Song TiO2 loaded 2D montmorillonite (2DMMT)-chitosan-poly (acrylic acid) hydrogel with 3D network structure as a novel adsorbent for methylene blue (MB) removal was investigated. The hydrogel was formed via the polymerization and molecular forces between 2DMMT and polysaccharide. Physicochemical analysis and factor experiments were implemented on hydrogel. The results implied that hydrogel possessed a porous structure and high surface area, facilitating the access and removal of MB. A completely removal of MB could be achieved in a small hydrogel dose of 0.2 g/L within 120 min even after 5 regeneration cycles, which could lower costs and enhance efficiency dramatically. MB adsorption onto hydrogel was reasonably correlated with pseudo-second-order kinetic model and Redlich-Peterson isotherm model. MB adsorption mechanism onto hydrogel was analyzed by FTIR, EDS and XPS. It was found MB molecules reacted with carboxyl groups as well as substituted cation from 2DMMT. Such hydrogel could not only realize the green/sustainable application in water treatment, but also guide the preparation for polymer materials from polyelectrolyte and nanoclay.Graphical abstractUnlabelled Image
       
  • Comparative studies on structure and physiochemical changes of millet
           starch under microwave and ultrasound at the same power
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Yang Li, Aijun Hu, Jie Zheng, Xiaoyi Wang As two novel starch modification technologies, the comparative study between microwave (MC) and ultrasound (UC) is of important significance for their applications. The objective of this work is to compare the changes of millet starch with MC and UC, focusing on the viscosity, swelling power (SP), transparency (TR), short-range molecular order (FT-IR spectrum), thermal properties (DSC), long-range molecular order (X-ray diffraction), in vitro enzymatic digestibility, and morphological properties. MC changed the type of the pasting curves form B-type to C-type, and the maximum decrease of the peak viscosity and relative crystallinity of MC starch was 74.9% and 100%, however, these changes for UC starch were only 14.8% and 23.2%. MC decreased the SP, TR, DSC, and ratio of absorbances at 1047/1022 cm−1, but UC caused opposite trend of these properties. Both MC and UC increased the in vitro enzymatic digestibility by 26.7% and 13.3%, respectively. MC also destroyed the original appearance of the starch granules and formed smaller and lamellar gel blocks. In conclusion, MC had greater influence on starch structure and properties than UC, even in a short period.Graphical abstractUnlabelled Image
       
  • Galactomannan from the seeds of Caesalpinia pulcherrima prevents
           indomethacin-induced gastrointestinal damage via neutrophil migration
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Fabrícia da Cunha Jácome Marques, Patrícia da Silva Pantoja, Victor Emanuel Araujo Matos, Renan Oliveira Silva, Samara Rodrigues Bonfim Damasceno, Álvaro Xavier Franco, Rômulo Couto Alves, Priscilla Fernanda Campos Justino, Marcellus Henrique Loiola Ponte de Souza, Judith Pessoa Andrade Feitosa, Rondinelle Ribeiro Castro, Pedro Marcos Gomes Soares Galactomannans are neutral polysaccharides isolated from the endosperm of some Leguminosae seeds. They consist of a (1 → 4) linked β-mannopyranosyl backbone partially substituted at O-6 with α-d-galactopyranosyl side groups. C. pulcherrima have anti-inflammatory and muco-adhesive proprieties. Acute gastritis is an inflammatory disease triggered by use of non-steroidal anti-inflammatory drugs. We investigated the gastroprotective effect of galactomannan obtained from the seeds of Caesalpinia pulcherrima L. (GM-CP) in acute gastritis model induced by indomethacin. Gastritis was induced with indomethacin (30 mg/kg, P.·O.) in female Swiss mice. Animal groups (n = 7) were pretreated with saline-dissolved GM-CP (3 mg/kg, 10 mg/kg, 30 mg/kg, P.O.) or vehicle 1 h before gastritis induction. Mice were euthanized seven hours after the induction. The stomach and blood samples were collected for analysis. At 10 mg/kg, GP-CP reduced the extension of macroscopic lesion and the loss of superficial cells by alleviating inflammatory symptoms (neutrophil infiltration, migration and adhesion of mesenteric leukocytes, production of TNF-α and thiobarbituric acid reactive species (TBARS) and helping to maintain mucin labeling of the tissue. Thus, the findings of the study suggest that GM-CP exhibits gastroprotective effects.
       
  • Efficient immobilization of phospholipase D on novel polymer supports with
           hierarchical pore structures
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Yan Li, Jia-Qin Wu, Neng-Bing Long, Rui-Feng Zhang In this article, novel epoxy resin-based hierarchical porous polymers (HPSs) have been prepared through a non-sol-gel and template-free approach using crystalline trimethylolpropane (TMP) as porogen. The polymers exhibit dimensional stability and possess 3-dimentional interconnected multi-scale pores. In range of 50 μm~10 nm are ultra-macro-pore in between skeleton, macro-pore on skeleton and meso-pore in network, respectively. The porosity and specific surface area can be adjusted in range of 91.2–82.5% and 225–156 m2/g, respectively. Using three kinds of hierarchical porous polymers as supports phospholipase D (PLD) was effectively immobilized through physical adsorption. Owing to high porosity of the support and improvement of mass transfer the loading amount of PLD reached as high as 223 mg/gsupport and the corresponding specific activity achieved up to 3.75 × 103 U/gsupport. Under optimized conditions and the phosphatidylserine (PS) yield reached 95.5% within 40 min at 45 °C. The immobilized PLD exhibited not only better storage stability and but also resistance to pH and thermal inactivation than free PLD. It was found that 73.5% of PS yield retained after 12 cycling reuses.
       
  • Evaluation of cartilage regeneration of chondrocyte encapsulated gellan
           gum-based hyaluronic acid blended hydrogel
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Won Kyung Kim, Joo Hee Choi, Myeong Eun Shin, Jin Woo Kim, Pil Yun Kim, Namyeong Kim, Jeong Eun Song, Gilson Khang Hydrogels have shown to be advantageous in supporting damaged cartilage because of its analogous to the extracellular matrix (ECM) of cartilage tissue. However, problems such as infection and inflammation are still a challenge to be solved. In terms of tissue engineering, natural materials are more advantageous than synthetic materials in biocompatibility and biodegradability status. Herein, physically blended nature-derived gellan gum (GG) hydrogel and hyaluronic acid (HA) hydrogel is suggested as a one of solution for cartilage tissue engineering material. The purpose of this study is to determine the effect of GG/HA hydrogel in vitro and in vivo. The chemical and mechanical properties were measured to confirm the compatibility of hydrogels for cartilage tissue engineering. The viability, proliferation, morphology, and gene expression of chondrocytes encapsulated in hydrogels were examined in vitro. Furthermore, the beneficial effect of the blended hydrogel was confirmed by performing the in vivo experiment. The chemical properties of hydrogels confirmed the well physically blended hydrogels. The mechanical studies of hydrogels displayed that as the content of HA increases, the swelling ratio was higher, compressive strength decreased and degradation was faster. Therefore, to use the hydrogel of GG and HA network, the proper amount must be blended. The in vitro study of chondrocytes encapsulated GG/HA hydrogel showed that the proper amount of HA enhanced the cell growth, attachment, and gene expression. The in vivo examination verified the advantageous effect of GG/HA hydrogel. Overall results demonstrate that GG/HA hydrogel is suitable for culturing chondrocyte and can be further applied for the treatment of cartilage defects.
       
  • Further stabilization of lipase from Pseudomonas fluorescens immobilized
           on octyl coated nanoparticles via chemical modification with bifunctional
           agents
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Nathalia Saraiva Rios, Eva Gomes Morais, Wesley dos Santos Galvão, Davino M. Andrade Neto, José Cleiton Sousa dos Santos, Felipe Bohn, Marcio A. Correa, Pierre Basílio Almeida Fechine, Roberto Fernandez-Lafuente, Luciana Rocha Barros Gonçalves The lipase from Pseudomonas fluorescens (PFL) was adsorbed on superparamagnetic NiZnFe2O4 octyl-nanoparticles via interfacial activation, producing the biocatalyst OCTYL-NANO-PFL. In order to further improve the stability of the immobilized lipase, the immobilized enzyme biocatalyst was chemically modified with different concentrations of diverse bifunctional molecules (glutaraldehyde (GA), divinylsulfone (DVS) or p-benzoquinone (BQ)). The concentrations of bifunctional agents were varied (0.5, 1, 2.5 and 5% (v/v for GA and DVS and w/v for BQ)). The results showed a greatly improved stability after chemical modification with all bifunctional molecules, mainly with 5% (v/v) GA or 1% (v/v) DVS. The biocatalysts OCTYL-NANO-PFL-GA 5% and -DVS 1% were about 60 folds more stable at pH 7 than the unmodified preparation and, at pH 5,>200 folds for 5% GA modified enzyme. The most stable BQ treated biocatalysts, OCTYL-NANO-PFL-BQ 0.5%, was about 8.3 more stable than OCTYL-NANO-PFL at pH 7, while was 20 fold more stable at pH 9.
       
  • Solid state synthesis of docosahexaenoic acid-loaded zinc oxide
           nanoparticles as a potential antidiabetic agent in rats
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Jihan Hussein, Mohamed F. Attia, Mona El Bana, Sherien M. El-Daly, Nadia Mohamed, Zakeria El-Khayat, Mehrez E. El-Naggar Our goal in this study is to improve the efficiency of docosahexaenoic acid (DHA) toward the enhancement of insulin signaling pathway in vivo via loading with zinc oxide nanoparticles (ZnO NPs). To this end, two consecutive steps were undertaken, preparation of ZnO NPs by one-step solid-state reaction in dry conditions and calcinated followed by loading DHA. Both developed nanoparticles, with and without DHA were then characterized by TEM, SEM, EDX, and Zetasizer. For comparison between free and loaded DHA, four groups of rats were prepared to receive different treatments. Group I; healthy rats (reference), group II; diabetes (streptozotocin-induced), group III and group IV are diabetes orally administered with free DHA and DHA-loaded ZnO NPs (10 mg/kg bw/day), respectively. Blood samples were collected and analyzed where the results demonstrated that fasting blood sugar and insulin resistance were significantly increased in diabetic group along with upgrading in oxidative stress parameters emphasizing the oxidative properties of streptozotocin. HPLC analysis of cell membrane fatty acids resulted in the reduction of omega-6 and 9 and elevation of omega-3 after free DHA and DHA-loaded ZnO NPs streptozotocin treatments. DHA-loaded ZnO NPs had high performance in enhancing insulin signaling pathway as expressed in changes of phosphatidylinositol 3-kinase (PI3K) levels.Graphical abstractUnlabelled Image
       
  • Effects of sulfated modification on the physicochemical properties and
           biological activities of β-glucans from Qingke (Tibetan hulless barley)
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Huan Guo, Hong-Yi Li, Lu Liu, Chao-Yi Wu, Hui Liu, Li Zhao, Qing Zhang, Yun-Tao Liu, Su-Qing Li, Wen Qin, Ding-Tao Wu In this study, the reaction conditions of sulfur trioxide-pyridine (SO3-Pyr) method for the modification of Qingke β-glucans (THB) were optimized by response surface methodology, and effects of different degrees of substitution (low, medium, and high) on the physicochemical properties, antioxidant activities, and in vitro hypolipidemic activities of THB were investigated. The optimal reaction conditions to obtain the high degree of substitution of sulfated β-glucans were as follows: ratio of SO3-Pyr to THB of 16.88 g/g, reaction time of 2.03 h, and reaction temperature of 57.54 °C. Results showed that sulfated modification significantly affected the water solubilities, apparent viscosities, molecular weights, and molar ratios of constituent monosaccharides of THB. Besides, the sulfated THB exhibited much better antioxidant activities (DPPH and nitric oxide radical scavenging activities, and reducing powers), in vitro binding properties (fat, cholesterol, and bile-acid binding capacities), and pancreatic lipase inhibition activities than that of THB. Indeed, the sulfated THB with higher degree of substitution has stronger antioxidant activities and in vitro hypolipidemic activities. Results suggested that the sulfated modification could be an efficient approach for the improvement of functional properties of THB, and sulfated THB could be further explored as functional food ingredients for industrial applications.
       
  • Production optimization, partial characterization and properties of an
           exopolysaccharide from Lactobacillus sakei L3
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Binbin Wang, Qiaozhi Song, Fangkun Zhao, Ye Han, Zhijiang Zhou The production optimization, partial characterization and properties of an exopolysaccharide (EPS) from Lactobacillus sakei L3 were performed. Sucrose concentration, initial pH and inoculation volume were the most significant variables that improved the L3 EPS production in a three-level Plackett-Burman design. The maximum EPS yield of 69.65 g/L (2.16-fold greater than the original yield) was obtained under optimal conditions of 127.80 g/L sucrose, initial pH 6.87 and 3.15% inoculation volume. Chemical analyses revealed that the observed EPS bioactivity was mainly due to the sugar moieties. The chain conformation was characterized by the Congo red test, a β-elimination reaction and circular dichroism, which indicated that the L3 EPS exhibited a random coil structure and O-linkages in aqueous solution, and the EPS concentration did not alter the EPS chain conformation but did modify the hydrogen-bond interactions and chirality of the polysaccharide. The purified L3 EPS exhibited high water solubility, probiotic effects and emulsification activity. The L3 EPS at 2.0 mg/mL formed a highly active and stable emulsion with sunflower oil, with EA, ES24, ES48 and ES72 indices of 62.30 ± 0.06%, 57.95 ± 0.18%, 42.73 ± 0.26% and 43.05 ± 0.08%, respectively. These results collectively describe a high-yield EPS with unique characteristics for exploitation in large-scale industrial food applications.Graphical abstractUnlabelled Image
       
  • Extraction, derivatization and antioxidant activity of bitter gourd
           polysaccharide
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Fang Chen, Gangliang Huang The effect of derivatization on the antioxidant activity of bitter gourd polysaccharide was investigated. Bitter gourd polysaccharide (P) was prepared with hot water. Carboxymethylated bitter gourd polysaccharide (CM-P) and acetylated bitter gourd polysaccharide (AcP) were successfully prepared, which were identified by IR and NMR spectra. On this basis, the antioxidant activities of three polysaccharides were tested, including hydroxyl radical scavenging capacity, DPPH radical scavenging capacity, and anti-lipid peroxidation capacity. The results showed that different chemical modifications had different enhancement on the antioxidant activities of bitter gourd polysaccharide. So, bitter gourd polysaccharide could be used to develop potential antioxidants.
       
  • Recent advances in thermal properties of hybrid cellulosic fiber
           reinforced polymer composites
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Senthilkumar Krishnasamy, Senthil Muthu Kumar Thiagamani, Chandrasekar Muthu Kumar, Rajini Nagarajan, Shahroze R.M., Suchart Siengchin, Sikiru O. Ismail, Indira Devi M.P Bio-composites are easy to manufacture and environmentally friendly, could reduce the overall cost and provide lightweight due to the low density of the natural fibers. In a bid to compete with the synthetic fiber reinforced composites, a single natural fiber composite may not be a good choice to obtain optimal properties. Hence, hybrid composites are produced by adding two or more natural fibers together to obtain improved properties, such as mechanical, physical, thermal, water absorption, acoustic and dynamic, among others. Regarding thermal stability, the composites showed a significant change by varying the individual fiber compositions, fiber surface treatments, addition of fillers and coupling agents. The glass transition temperature and melting point obtained from the thermomechanical analysis and differential scanning calorimetry are not the same values for several hybrid composites, since the volume variation was not always parallel with the enthalpy change. However, the difference between the temperature calculated from the thermomechanical analysis and differential scanning calorimetry was lower. Significantly, this critical reviewed study has a potential of guiding all composite designers, manufacturers and users on right selection of composite materials for thermal applications, such as engine components (covers), heat shields and brake ducts, among others.
       
  • Characterization of the complete mitochondrial genomes of two species of
           the genus Aphaena Guérin-Méneville (Hemiptera: Fulgoridae) and its
           phylogenetic implications
    • Abstract: Publication date: 1 December 2019Source: International Journal of Biological Macromolecules, Volume 141Author(s): Wenqian Wang, Yixin Huang, Charles R. Bartlett, Fanmei Zhou, Rui Meng, Daozheng Qin The complete mitochondrial genomes (mitogenomes) of Aphaena (Callidepsa) amabilis and Aphaena (Aphaena) discolor nigrotibiata were sequenced. The mitogenomes of these two species are 16,237 bp and 16,116 bp in length with an A + T content of 77.9% and 77.0%, respectively. Each contains 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs) and a control region (A + T-rich region). All PCGs initiate with the standard start codon of ATN and terminate with the complete stop codon of TAA or TAG except for atp6, where nad1 ends with an incomplete T codon. All tRNAs have the typical clover-leaf structure except for trnS1 and trnV which have a reduced DHU arm. Moreover, these two mitogenomes have trnL2, trnR and trnT with an unpaired base in the acceptor stem. The putative A + T-rich region includes multiple types of tandem repeat regions. These phylogenetic analyses are reconstructed based on 13 protein-coding genes of 25 auchenorrhynchan mitogenomes, with both maximum likelihood and Bayesian analyses yielding robust identical phylogenetic trees. These results support a monophyletic Auchenorrhyncha and the relationship (Pyrops + (Lycorma + Aphaena)) within Fulgoridae.
       
  • Synthesis of cellulose acetate/chitosan/SWCNT/Fe3O4/TiO2 composite
           nanofibers for the removal of Cr(VI), As(V), Methylene blue and Congo red
           from aqueous solutions
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Abolfazl ZabihiSahebi, Shahnaz Koushkbaghi, Mohammad Pishnamazi, Anis Askari, Reza Khosravi, Mohammad Irani The potential of electrospun cellulose acetate/chitosan/single walled carbon nanotubes/ferrite/titanium dioxide (CA/chitosan/SWCNT/Fe3O4/TiO2) nanofibers was investigated for the removal of Cr(VI), As(V), Methylene blue and Congo red from aqueous solutions via the adsorption and photocatalytic reduction processes. The properties of synthesized SWCNT/Fe3O4/TiO2 and fibers were characterized using TEM, SEM, FTIR, XRD, TGA and BET analysis. In adsorption process, the influence of adsorbent type including SWCNT to Fe3O4 ratio, TiO2 to SWCNT/Fe3O4 ratio and SWCNT/Fe3O4/TiO2 concentration as well as the adsorption parameters including pH, contact time, and initial concentration of adsorbates on the Cr(VI), As(V), Methylene blue and Congo red adsorption in a batch mode was investigated. The reusability of nanofibers was also investigated for five adsorption-desorption cycles. The photocatalytic reduction of Cr(VI), As(V), Methylene blue and Congo red was also investigated using various nanofibrous catalysts. The obtained results indicated that the removal of Cr(VI) and As(V) using CA/chitosan/SWCNT/Fe3O4/TiO2 nanofibrous adsorbent via adsorption process could be preferred for the lower concentrations of metal ions. The photocatalytic reduction was an effective method for the Cr(VI), As(V) removal at higher concentrations and degradation of Methylene blue and Congo red under both lower and higher concentrations of azo dyes.
       
  • Immobilization of xylanase on modified grafted alginate polyethyleneimine
           bead based on impact of sodium cation effect
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Faten A. Mostafa, Abeer A.A. El Aty, Mohamed E. Hassan, Ghada E.A. Awad Alginate- polyethyleneimine gel beads modified by using 0.3 M Na+ were used for covalent immobilization of Aspergillus flavus xylanase. SEM images showed distorted structure with addition of Na+ that impaired the egg-box structure formation offered much covalent binding with xylanase. Immobilization onto (Alg+PEI/Na+) showed an enhancement in the operational stability, immobilization efficiency as well as immobilization yield. Covalent immobilization of xylanase onto (Alg+PEI/Na+) enhanced xylanase activity over a wide range of pHs (4–5.5) comparable to its free formula. As well as an increase in reaction temperature up to 60°C. However, immobilized formula of enzyme showed abroad thermal stability that it retained 79.0% of its initial activity at 70°C up to 30 min whereas, free formula completely lost its activity at this temperature. Thermodynamics studies showed an enhancement in thermal stability at high temperature for the immobilized xylanase. i.e. At 70°C the t1/2 and D-value for free formula of enzyme increased from 24 to165 min and from 79.95to 548.23 min, respectively. Moreover, the enzyme stability enhancement for immobilized formula of xylanase was proved with a remarkable increase in enthalpy and free energy. 93% of the immobilized xylanase activity was retained over 6 weeks of storage at -4°C.
       
  • Methionine γ-lyase in enzyme prodrug therapy: An improvement of
           pharmacokinetic parameters of the enzyme
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Elena A. Morozova, Vitalia V. Kulikova, Natalya V. Anufrieva, Alexey N. Minakov, Alexandr S. Chernov, Georgij B. Telegin, Svetlana V. Revtovich, Vasily S. Koval, Tatyana V. Demidkina Citrobacter freundii methionine γ-lyase (MGL), in addition to the physiological reaction, catalyzes the β-elimination reaction of S-alk(en)yl-L-cysteine sulfoxides to yield thiosulfinates, which have antibacterial activity. We have obtained the mutant form C115H MGL, which cleaves S-alk(en)yl-L-cysteine sulfoxides more effectively than the wild type enzyme does. The binary system MGL/S-alk(en)yl-L-cysteine sulfoxides may be considered as a new pharmacological pair in enzyme prodrug therapy (EPT). Despite of the successful application of this pair in antibacterial studies in vitro, in vivo experiments may lead to several problems typical of therapeutic proteins including a relatively short-lasting biological activity. To circumvent these problems, we have investigated several approaches to improve safety and efficacy of the enzyme component of the pharmacological pair. This included covalent attachment of poly(ethylene glycol) to the enzyme, its encapsulation in liposomes and polymeric vesicles (PICsomes). The steady-state and pharmacokinetic parameters of modified/encapsulated enzyme were determined. It was demonstrated that the encapsulation in PICsomes prolongs in vivo stability of C115H MGL to over 42 h compared to PEGylated enzyme (3 h). Antibacterial activity of binary system (“pharmacological pair”) modified/encapsulated enzyme/S-alk(en)yl-L-cysteine sulfoxides was tested and remained the same as for the naked enzyme. Thus, the usage of MGL-loaded PICsomes as enzymatic nanoreactors in ETP to produce antimicrobial thiosulfinates is promising.
       
  • Preparation, properties, and structural characterization of
           β-glucan/pullulan blend films
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Jinyu Chang, Wanrong Li, Qin Liu, You Zhou, Xuan Chen, Qingyun Lyu, Gang Liu This study investigates the physico-mechanical and structural properties of β-glucan (BG)/pullulan (PUL) composite edible films successfully prepared with 0–0.3 g of BG. Results demonstrated that BG addition significantly increases the elongation at break (p 
       
  • Antibacterial and antioxidant assessment of cellulose
           acetate/polycaprolactone nanofibrous mats impregnated with propolis
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Kamyar Khoshnevisan, Hassan Maleki, Hadi Samadian, Maryam Doostan, Mohammad Reza Khorramizadeh Cellulose acetate (CA) electrospun nanofibers are one of the most practical cellulosic material which normally applied as carriers for drug delivery and wound healing systems. In this study, CA and polycaprolactone (PCL) was applied to fabricate the electrospun nanofibrous for wound dressing application. Propolis is a resin-like macromolecule produced by honeybees from the buds and diverse plants. Among many applications of this macromolecule, it has been occasionally employed directly to the skin for wound healing applications. Herein, owing to the significance of propolis, CA/PCL nanofibers were impregnated with a propolis-extracted solution to reach antibacterial and antioxidant mat. The scanning electron microscopy (SEM) images revealed that electrospinning of 10% (w/w) CA along with 14% (w/w) PCL produced excellent nanofibers compared to the resultant nanofibers. Hydrophobicity/hydrophilicity nature of CA/PCL mats was measured using water contact-angle method before and after treatment with NaOH. The nanofibrous mats exhibited a high water absorption capacity of about 400%. Antioxidant effect was measured by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay and propolis-CA/PCL presented a high antioxidant activity. Additionally, propolis-CA/PCL mats showed antibacterial activity against both the Gram-positive and Gram-negative bacteria. In conclusion, our results have confirmed that the propolis-impregnated CA/PCL mats have provided an appropriate surface for wound healing system.Graphical abstractUnlabelled Image
       
  • Computational design of Bacillus licheniformis RN-01 levansucrase for
           control of the chain length of levan-type fructooligosaccharides
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Pongsakorn Kanjanatanin, Rath Pichyangkura, Thassanai Sitthiyotha, Thanapon Charoenwongpaiboon, Karan Wangpaiboon, Surasak Chunsrivirot Levansucrase (LS) from Gram-positive bacteria generally produces a large quantity of levan polymer, a polyfructose with glucose at the end (GFn) but a small quantity of levan-type fructooligosaccharides (LFOs). The properties of levan and LFOs depend on their chain lengths, thereby determining their potential applications in food and pharmaceutical industries such as prebiotics and anti-tumor agents. Therefore, an ability to redesign and engineer the active site of levansucrase for synthesis of products with desired degree of polymerization (DP) is very beneficial. We employed computational protein design, docking and molecular dynamics to redesign and engineer the active site of Bacillus licheniformis RN-01 levansucrase for production of LFOs with DP up to five (GF4), using two approaches: 1) blocking oligosaccharide binding track of GF3-LS complex with large aromatic residues and 2) eliminating hydrogen bond interactions between terminal glucose of GF4 and side chains of binding residues of GF4-LS complex. The designed enzymes and their product patterns from these two approaches were experimentally characterized. The experimental results show that the first approach was successful in creating N251W and N251W/K372Y mutants that synthesized LFOs with DP up to five. This work illustrates how computer-aided approaches can offer novel opportunities to engineer enzymes for desired products.
       
  • Recombinant porcine NK-lysin inhibits the invasion of hepatocellular
           carcinoma cells in vitro
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Ajab Khan, Kuohai Fan, Na Sun, Wei Yin, Yaogui Sun, Panpan Sun, Ali Raza Jahejo, Hongquan Li The therapeutics having ability to target cancer cells specifically and exhibit nominal cytopathic effect on normal healthy cells are highly significant for cancer therapeutic applications. Recombinant porcine natural killer lysin (rpNK-lysin) has proven cationic anti-bacterial and anti-tumor peptide. Herein, we report its anti-invasion and anti-metastasis effects on hepatocellular carcinoma (HCC) cells in vitro. We first investigate the maximum non-toxic concentration (MNTC) of rpNK-lysin for the normal hepato cells (L-02). Using MNTC rpNK-lysin, we explore anti-proliferative, anti-adhesive, anti-invasive and anti-metastatic effect of rpNK-lysin on three different HCC cells lines (SMMC-7721, 97-H and HepG2) through MTT, wound-healing, adhesion and invasion assay along with mRNA and protein expression. The results reveal that rpNK-lysin has potential to specifically inhibit HCC cells growth in a dose and time-dependent manner with a little cytopathic effect on the L-02 cells, effectively reduce migration, adhesion and invasion ability of HCC cells. rpNK-lysin significantly reduce Fascin1 expression, which subsequently decrease β-catenin expression and metaloproteinases (MMP-2 and MMP9). This study suggest that MNTC rpNK-lysin has an anti-invasion and anti-metastasis effect on HCC cells in vitro through inhibition of Fascin 1 expression which regulates Wnt/β-catenin signaling pathway by inducing β-catenin degradation and subsequently results in suppression of MMP-2 and MMP9 expression.
       
  • A novel hydrochloride-free chitosan oligosaccharide production method to
           improve taste
    • Abstract: Publication date: 1 November 2019Source: International Journal of Biological Macromolecules, Volume 140Author(s): Seiji Kurozumi, Masatoshi Kiyose, Takako Noguchi, Kimihiko Sato Chitosan oligosaccharide hydrochloride (COS-HCl) has an unpleasant taste. To improve this taste, we used an enzymatic hydrolysis with chitosan to manufacture hydrochloride-free chitosan oligosaccharide (HFCOS). We found that HFCOS powder with weight-average molecular weight (Mw) of approximately 1000 and a high degree of deacetylation can be obtained from amorphous chitosan in carbonated water by enzymatic hydrolysis because amorphous chitosan slightly dissolves in carbonated water. HFCOS was stable enough to be atomized by spray-drying. However, HFCOS yield was quite low (15.7%). There were few chloride ions in HFCOS (0.1% ± 0.1%), in contrast to the number of chloride ions in COS-HCl (16.6% ± 0.6%) with statistical significance (p 
       
 
 
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