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  Subjects -> SCIENCES: COMPREHENSIVE WORKS (Total: 374 journals)
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Middle East Journal of Science
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Online) 2618-6136
Published by DergiPark Homepage  [185 journals]
  • SOME NOVEL SCHIFF BASE DERIVATIVES AS PROMISING CHOLINESTERASE INHIBITORS
           WITH ANTIOXIDANT ACTIVITY AGAINST ALZHEIMER’S DISEASE: SYNTHESIS,
           CHARACTERIZATION AND BIOLOGICAL EVALUATION

    • Authors: Ercan ÇINAR; Mehmet BOĞA, Giray TOPAL, Reşit ÇAKMAK
      Abstract: In this manuscript, five novel Schiff base derivatives containing a pyrazolone ring and a sulfonate moiety (6-10) except for 9 were designed, obtained for the first time and characterized by three spectroscopic techniques. The inhibition performances of these moleucles synthesized in two steps against cholinesterases, namely acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were evaluated. By DPPH and ABTS assays, antioxidant activities of these molecules were also examined. In AChE assay, compound 6 (95.87±1.59 % inhibition) inhibited this enzyme better than galanthamine (76.98±0.42 % inhibition). In BChE assay, compound 10 with 87.92±1.08% inhibition value in the series indicated the highest activity compared to galanthamine (76.30±0.28 % inhibition). In ABTS radical scavenging assay, compounds 7, 8 and 9 except for 6 and 10 indicated higher antioxidant activities compared to butylated hydroxytoluene (BHT). It is believed that these results may contribute to the design and synthesis of novel antioxidant agents, AChE and BChE inhibitors.
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • THE CHEMISTRY MECHANISM OF HAIR DYES

    • Authors: Arzu YILDIRIM; Nur Belinda DEMİR, Berfin AK İZGİ, Büşra Nur ERKOL, Çağla ÖZSU, Gülşah EŞLİK AYDEMİR, Mine MUSTAFAOĞLU, Murat KIZIL, Nubar AYHAN, Sevil EMEN
      Abstract: One of the oldest and most well-known cosmetics, hair color has been used by numerous ancient cultures throughout history on both men and women. It involves treating hair with various chemical compounds for changing hair color. According to how long they remain in the hair, these products are primarily divided into two categories: temporary and permanent. This classification is consistent with the types of active substances used in the dyeing process as well as the dyeing method itself, which are referred to as non-oxidative and oxidative hair dye products, respectively. Permanent hair dyes often consist of active chemicals that are not dyed but are oxidized to provide the desired color. As a result, the phrase "oxidative hair dye" was emerged. The precursor part and coupler part are the two main ingredients in formulations for oxidative hair dyes. Quinonediimine intermediates are momentary compounds that are generated when combined with hydrogen peroxide (developer). As a result, the coupler agent and these compounds interact to form the appropriate hair dye molecule. Notably, the entire dyeing process requires both an alkaline medium and an oxidizing agent, often hydrogen peroxide, to ensure that the staining agents reach the cuticle widely. This review's objective is to provide information about hair dye formulations and mechanisms of action as well as repairing damaged hair and new applications.
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • HIROTA METHOD AND SOLITON SOLUTIONS

    • Authors: Barış YAPIŞKAN
      Abstract: Solitons are an important class of solutions to nonlinear differential equations which appear in different areas of physics and applied mathematics. In this study we provide a general overview of the Hirota method which is one of the most powerful tool in finding the multi-soliton solutions of nonlinear wave and evaluation equations. Bright and dark soliton solutions of nonlinear Schrödinger equation are discussed in detail
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • SYNTHESIS OF NOVEL BIS(PHOSPHINO)AMINE-RUII(ACAC)2 COMPLEXES, AND
           INVESTIGATION OF CATALYTIC ACTIVITY IN TRANSFER HYDROGENATION

    • Authors: Duygu ELMA KARAKAŞ; Uğur IŞIK, Murat AYDEMİR, Feyyaz DURAP, Akın BAYSAL
      Abstract: In this study, reactions of (PPh2)2NCH2CH2N(PPh2)2 (L1) and {(PPh2)2NCH2CH2}3N (L2) with [RuII(acac)2(CH3CN)2] led to the production of new dinuclear complex [Ru(acac)2]2(L1) (1) and trinuclear complex [Ru(acac)2]3(L2) (2). Complex 1 and 2 are excellent candidates for the role of catalyst precursors in the transfer hydrogenation (TH) of acetophenone and its derivatives. Compared to complex (1), the trinuclear complex (2) is an exceptional catalyst, producing the corresponding alcohols in 98–99% yields in 20 minutes at 80 oC (TOF≤300 h-1) for the TH process. A comparison of the catalytic properties of the complexes is also briefly discussed. Complex structures have also been characterized by combining nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR), and elemental analysis.
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • DETERMINATION OF SOME BIOACTIVITIES OF Convallaria majalis L. (LILY OF THE
           VALLEY), ISOLATION PHARMACEUTICAL ACTIVE INGREDIENT AND INVESTIGATION ITS
           INDUSTRIAL USEAGE

    • Authors: Nazan DEMİR; Sıla Nezahat DAŞDEMİR, Alevcan KAPLAN, Yaşar DEMİR
      Abstract: In this study, some biological activities of Convallaria majalis L. (Asparagaceae), which grows naturally in Muğla and its surroundings and attracts attention with its pleasant smell, were determined, and the isolation of drug active substances and industrial usability were investigated. For this purpose, the protease enzyme that catalyzes the hydrolysis of proteins, which is one of the most important enzyme groups in both industrial and biochemical applications, into peptides and amino acids was purified from C. majalis. Protease enzyme was purified using TPP (Three Phase Partitioning) method. Optimum pH and optimum temperature for the enzyme, Km and Vmax values for casein, azocasein, gelatin, hemoglobin, azoalbumin substrates were determined. SDS-PAGE was used to check the purity of the purified protease enzyme. The molecular weight of the enzyme was calculated as 54.347 kDa using gel filtration chromatography. The effects of SDS, EDTA, β-mercaptoethanol compounds and Mg2+, Ca2+, Mn2+, Ni2+, Hg2+, Fe2+, Fe3+ cations, 10 mM, 1 mM, 0.1 mM concentrations on enzyme activity were investigated. Volatile and flavoring components analyzed with Headspace GC/MSD. It was determined that C.majalis flowers contain volatile organic compounds, citronellol (9.6%), geraniol (8.4%), benzyalcohol (35%), phenylacetonitrile (3.0%), farnesol (1.9 %) and 2,3-dihydrofarnesol (0.88 %), green grassy notes: (Z)-3-hexen-1-ol (11 %), (Z)-3-hexenyl acetate (7.8%). As a result of the work, it was determined that the aromatic of C. majalis can be used as an active ingredient and it has been concluded that there is an industrial use.
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • SOLUTION FOR STEKLOV BOUNDARY VALUE PROBLEM INVOLVING THE P(X)- LAPLACIAN
           OPERATORS

    • Authors: Zehra YÜCEDAĞ; Vahup MURAD
      Abstract: In this paper, we concerned with Steklov boundary value problem involving - Laplacian operator. By means of the Mountain Pass theorem together with Ambrosetti- Rabinowitz condition, we prove the existence nontrivial weak of solutions in Sobolev spaces with variable exponent under appropriate conditions on f(x,u) .
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • DYNAMIC SUBSTANCE RESEARCH IN DOMESTIC AND IMPORTED BLACK TEA SOLD IN
           TURKEY

    • Authors: Kasım TAKIM; Mehmet Emin AYDEMİR
      Abstract: Tea is a popular product known worldwide with health benefits for consumers. For centuries, it has been considered a safe and healthy beverage. Although the tea plant has many beneficial effects on human health, the chemicals that can be found in the tea plant can cause negative effects on health. Recently, the use of dyes in teas comes to the fore among imitations or adulterations made in foods recently. These substances pose a health risk.The purpose of this study; sold in the provinced in Turkey's Southeast Anatolia and Eastern Anatolia regions and to assess the presence of dye in the domestic and imported tea. In the study (Mardin; 7, Sirnak, 3, Van, 15, Diyarbakir, 13, Siirt, 9, Batman; 4, Gaziantep, 14, Kilis, 4 and Sanliurfa; 10) Iran, Sri Lanka, India and originating in Turkey A total of 79 samples were taken from the black teas and a wool yarn dyeing analysis with ( GMMAY S: 94-107 ) method was performed to look for dyes. The analyzes were carried out in an advanced private laboratory with European Union accreditation. According to the analysis results, no dye was detected in any of the tea samples. According to these results, it was concluded that no dyestuff is used in the harvesting, processing, drying and packaging stages of local and imported teas sold in the Southeastern Anatolia and Eastern Anatolia regions. Turkey determined to make the presence of dyes in general in the domestic and imported tea in other regions such analysis is required.
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • MODIFICATION OF ASPERGILLUS NIGER ATCC 11414 GROWTH FOR THE ENHANCEMENT OF
           PROTEASE PRODUCTION BY THE EFFECT OF NATURAL MICROPARTICLES

    • Authors: Hasan Buğra ÇOBAN
      Abstract: Even though fungal proteases under interest, bulk fungal growth during the productions decreases the overall mass transfer and consequently the yield. In this study, instead of inorganic microparticles, various organic microparticles were used in the production medium to prevent bulky fungal growth and increase the homogeneity. Results showed that all microparticle additions did not only increased the maximum enzyme activity but also decreased the required time to reach the highest value. Among organic microparticle addition productions, the highest protease activity was reported as 100,76 U/ml in walnut shells added flasks, which was approximately 1,4 fold higher compared to highest activity obtained in the control production. It was also reported that microparticle addition increased the homogeneity but also resulted in higher viscosity due to hyphae type growth. Additionally, evaluation of various storage temperatures showed that produced enzyme lost only its 7% activity at 4oC at the end of 25 days.
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • SEVERE PRE-ECLAMPSIA COMPLICATED BY HELLP SYNDROME IN THE HOFFBAUER AND
           

    • Authors: Yusuf NERGİZ; Şebnem NERGİZ ÖZTÜRK, Fırat AŞIR, Engin DEVECİ, Muhammet Erdal SAK, Mehmet Sıddık EVSEN, Selcuk TUNİK, Uğur ŞEKER
      Abstract: The aim of this study was to evaluate the immunohistochemistry and ultrastructural of syncytiotrophoblast and Hoffbauer cells in placental villi of HELLP syndrome patients. Placental samples with twenty control (normotensive) and twenty HELLP syndrome were fixed in 10% neutral formalin solution for paraffin-embedding wax protocol. Placental samples were fixed in 2.5% buffered glutaraldehyde and then, in 1% osmium tetra oxide for routine electron microscopic procedure. When the HELLP group fetal placental sections were examined, intracytoplasmic edema in syncytiotrophoblast, degenerative vacuoles and degenerative findings on cell surface membranes were observed. Moreover, villous edema was remarkable. The number of CD68 positive Hoffbauer cells per villus control group sections was 0.23 ± 0.02 and the number of CD68 positive cells per villus in HELLP group placenta sections was 0.83 ± 0.12 . The increase in the number of Hoffbauer cells per villus in the HELLP group was statistically significant (p
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • EVALUATION OF SERUM VITAMIN D LEVELS ACCORDING TO SEASON, AGE, AND GENDER
           IN MARDIN PROVINCE AND ITS SURROUNDINGS

    • Authors: Ahmet DÜNDAR
      Abstract: Vitamin D is a steroid in character and a fat-soluble vitamin. It is produced primarily from cholesterol in the skin and is also taken up in a small amount in the diet. 25(OH)D3 levels are used as an indirect measure of vitamin D levels. Our aim was to investigate the variation in serum 25(OH)D3 levels of patients admitted to the hospital in and around Mardin based on gender, season, and age. 25(OH)D3 concentrations were evaluated at Mardin Training and Research Hospital between 01.01.2017 and 01.01.2020. Our study established subgroups according to gender, season, age, and 25(OH)D3 status. 25(OH)D3 concentration was measured using the chemiluminescence method. A significant decrease was observed in the 25(OH)D3 levels of female (13.62±11.53 ng/ml) patients compared to male patients (12.14±9.38 ng/ml).. A significant increase was detected in the summer and autumn seasons compared to winter and spring (p
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
  • REMOVAL OF HEAVY METALS FROM SYNTHETIC ACIDIC MINE WATER USING RECYCLED
           AGGREGATES

    • Authors: Gülşen TOZSİN
      Abstract: Acid mine drainage (AMD), a highly acidic and sulfate (SO42-)-rich solution, is an environmental concern related to the release of metal-containing wastewater from mining areas into the environment. In this study, recycled aggregates (RA) produced from concrete debris were used in the treatment of acidic mine water contaminated with heavy metals. For a model synthetic acidic mine water with a pH of 2.31, SO42- and iron (Fe) concentrations of 5200 mg L-1 and 700 mg L-1, respectively, RA increased the pH value to 11.18 and reduced the SO42- and Fe concentrations by 90.51% and 100%, respectively, at RA/AMD ratio of 100 mg L-1 after 300 minutes of shaking at room temperature in batch experiments. The test results also showed that 100% of copper (Cu), zinc (Zn), manganese (Mn), silver (Pb) and cobalt (Co) concentrations were removed at this ratio and shaking time. This study demonstrates that RA have significant potential to neutralize acidity and remove heavy metals from AMD, a serious problem for ecological systems and health.
      PubDate: Sat, 31 Dec 2022 00:00:00 +030
       
 
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