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  Subjects -> BUSINESS AND ECONOMICS (Total: 3283 journals)
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BUSINESS AND ECONOMICS (1210 journals)                  1 2 3 4 5 6 7 | Last

Showing 1 - 200 of 1566 Journals sorted alphabetically
4OR: A Quarterly Journal of Operations Research     Hybrid Journal   (Followers: 10)
Abacus     Hybrid Journal   (Followers: 14)
Accounting Forum     Hybrid Journal   (Followers: 25)
Acta Amazonica     Open Access   (Followers: 5)
Acta Commercii     Open Access   (Followers: 4)
Acta Oeconomica     Full-text available via subscription   (Followers: 3)
Acta Scientiarum. Human and Social Sciences     Open Access   (Followers: 8)
Acta Universitatis Danubius. Œconomica     Open Access   (Followers: 3)
Acta Universitatis Nicolai Copernici Zarządzanie     Open Access   (Followers: 4)
AD-minister     Open Access   (Followers: 3)
Adam Academy : Journal of Social Sciences / Adam Akademi : Sosyal Bilimler Dergisi     Open Access  
Admisi dan Bisnis     Open Access  
ADR Bulletin     Open Access   (Followers: 6)
Advances in Developing Human Resources     Hybrid Journal   (Followers: 25)
Advances in Economics and Business     Open Access   (Followers: 14)
AfricaGrowth Agenda     Full-text available via subscription   (Followers: 1)
African Affairs     Hybrid Journal   (Followers: 64)
African Development Review     Hybrid Journal   (Followers: 35)
African Journal of Business and Economic Research     Full-text available via subscription   (Followers: 3)
African Journal of Business Ethics     Open Access   (Followers: 6)
African Review of Economics and Finance     Open Access   (Followers: 3)
Afro-Asian Journal of Finance and Accounting     Hybrid Journal   (Followers: 7)
Afyon Kocatepe Üniversitesi İktisadi ve İdari Bilimler Fakültesi Dergisi     Open Access   (Followers: 3)
Agronomy     Open Access   (Followers: 10)
Akademik Yaklaşımlar Dergisi     Open Access  
Akademika : Journal of Southeast Asia Social Sciences and Humanities     Open Access   (Followers: 7)
Alphanumeric Journal : The Journal of Operations Research, Statistics, Econometrics and Management Information Systems     Open Access   (Followers: 5)
American Economic Journal : Applied Economics     Full-text available via subscription   (Followers: 188)
American Enterprise Institute     Free  
American Journal of Business     Hybrid Journal   (Followers: 17)
American Journal of Business and Management     Open Access   (Followers: 54)
American Journal of Business Education     Open Access   (Followers: 12)
American Journal of Economics and Business Administration     Open Access   (Followers: 27)
American Journal of Economics and Sociology     Hybrid Journal   (Followers: 31)
American Journal of Evaluation     Hybrid Journal   (Followers: 14)
American Journal of Finance and Accounting     Hybrid Journal   (Followers: 21)
American Journal of Health Economics     Full-text available via subscription   (Followers: 13)
American Journal of Industrial and Business Management     Open Access   (Followers: 24)
American Journal of Medical Quality     Hybrid Journal   (Followers: 8)
American Law and Economics Review     Hybrid Journal   (Followers: 27)
ANALES de la Universidad Central del Ecuador     Open Access   (Followers: 3)
Ankara University SBF Journal     Open Access  
Annales de l'Institut Henri Poincare (C) Non Linear Analysis     Full-text available via subscription   (Followers: 1)
Annals in Social Responsibility     Full-text available via subscription  
Annals of Finance     Hybrid Journal   (Followers: 30)
Annals of Operations Research     Hybrid Journal   (Followers: 10)
Annual Review of Economics     Full-text available via subscription   (Followers: 36)
Anuario Facultad de Ciencias Económicas y Empresariales     Open Access   (Followers: 2)
Applied Developmental Science     Hybrid Journal   (Followers: 3)
Applied Economics     Hybrid Journal   (Followers: 43)
Applied Economics Letters     Hybrid Journal   (Followers: 30)
Applied Economics Quarterly     Full-text available via subscription   (Followers: 9)
Applied Financial Economics     Hybrid Journal   (Followers: 27)
Applied Mathematical Finance     Hybrid Journal   (Followers: 7)
Applied Stochastic Models in Business and Industry     Hybrid Journal   (Followers: 6)
Arab Economic and Business Journal     Open Access   (Followers: 4)
Archives of Business Research     Open Access   (Followers: 6)
Arena Journal     Full-text available via subscription   (Followers: 1)
Argomenti. Rivista di economia, cultura e ricerca sociale     Open Access   (Followers: 4)
ASEAN Economic Bulletin     Full-text available via subscription   (Followers: 5)
Asia Pacific Business Review     Hybrid Journal   (Followers: 8)
Asia Pacific Journal of Human Resources     Hybrid Journal   (Followers: 316)
Asia Pacific Journal of Innovation and Entrepreneurship     Open Access  
Asia Pacific Viewpoint     Hybrid Journal  
Asia-Pacific Journal of Business Administration     Hybrid Journal   (Followers: 5)
Asia-Pacific Journal of Operational Research     Hybrid Journal   (Followers: 3)
Asia-Pacific Management and Business Application     Open Access   (Followers: 1)
Asian Business Review     Open Access   (Followers: 3)
Asian Case Research Journal     Hybrid Journal   (Followers: 1)
Asian Development Review     Open Access   (Followers: 13)
Asian Economic Journal     Hybrid Journal   (Followers: 8)
Asian Economic Papers     Hybrid Journal   (Followers: 7)
Asian Economic Policy Review     Hybrid Journal   (Followers: 4)
Asian Journal of Accounting and Governance     Open Access   (Followers: 3)
Asian Journal of Business Ethics     Hybrid Journal   (Followers: 9)
Asian Journal of Social Sciences and Management Studies     Open Access   (Followers: 7)
Asian Journal of Sustainability and Social Responsibility     Open Access   (Followers: 1)
Asian Journal of Technology Innovation     Hybrid Journal   (Followers: 8)
Asian-pacific Economic Literature     Hybrid Journal   (Followers: 5)
AStA Wirtschafts- und Sozialstatistisches Archiv     Hybrid Journal   (Followers: 5)
ATA Journal of Legal Tax Research     Hybrid Journal   (Followers: 4)
Atlantic Economic Journal     Hybrid Journal   (Followers: 11)
Australasian Journal of Regional Studies, The     Full-text available via subscription   (Followers: 1)
Australian Cottongrower, The     Full-text available via subscription   (Followers: 1)
Australian Economic Papers     Hybrid Journal   (Followers: 34)
Australian Economic Review     Hybrid Journal   (Followers: 3)
Australian Journal of Maritime and Ocean Affairs     Hybrid Journal   (Followers: 9)
Balkan Region Conference on Engineering and Business Education     Open Access   (Followers: 1)
Baltic Journal of Real Estate Economics and Construction Management     Open Access   (Followers: 2)
Banks in Insurance Report     Hybrid Journal   (Followers: 1)
BBR - Brazilian Business Review     Open Access   (Followers: 4)
Benchmarking : An International Journal     Hybrid Journal   (Followers: 10)
Benefit : Jurnal Manajemen dan Bisnis     Open Access   (Followers: 1)
BER : Consumer Confidence Survey     Full-text available via subscription   (Followers: 3)
BER : Economic Prospects : An Executive Summary     Full-text available via subscription  
BER : Economic Prospects : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Intermediate Goods Industries Survey     Full-text available via subscription   (Followers: 1)
BER : Manufacturing Survey : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Motor Trade Survey     Full-text available via subscription  
BER : Retail Sector Survey     Full-text available via subscription   (Followers: 1)
BER : Retail Survey : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Survey of Business Conditions in Building and Construction : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Manufacturing : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Retail : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Trends : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Wholesale Sector Survey     Full-text available via subscription  
Berkeley Business Law Journal     Free   (Followers: 9)
Beykent Üniversitesi Sosyal Bilimler Dergisi     Open Access  
Bio-based and Applied Economics     Open Access   (Followers: 1)
Biodegradation     Hybrid Journal   (Followers: 1)
Biology Direct     Open Access   (Followers: 7)
Bitlis Eren Üniversitesi İktisadi Ve İdari Bilimler Fakültesi Akademik İzdüşüm Dergisi     Full-text available via subscription  
BizInfo (Blace) Journal of Economics, Management and Informatics     Open Access  
Black Enterprise     Full-text available via subscription  
Board & Administrator for Administrators only     Hybrid Journal  
Boletim Técnico do Senac     Open Access  
Border Crossing : Transnational Working Papers     Open Access   (Followers: 4)
Briefings in Real Estate Finance     Hybrid Journal   (Followers: 5)
British Journal of Industrial Relations     Hybrid Journal   (Followers: 36)
Brookings Papers on Economic Activity     Open Access   (Followers: 48)
Brookings Trade Forum     Full-text available via subscription   (Followers: 3)
BRQ Business Research Quarterly     Open Access   (Followers: 2)
Building Sustainable Legacies : The New Frontier Of Societal Value Co-Creation     Full-text available via subscription   (Followers: 1)
Bulletin of Economic Research     Hybrid Journal   (Followers: 17)
Bulletin of Geography. Socio-economic Series     Open Access   (Followers: 5)
Bulletin of Indonesian Economic Studies     Hybrid Journal   (Followers: 3)
Bulletin of the Dnipropetrovsk University. Series : Management of Innovations     Open Access   (Followers: 1)
Business & Entrepreneurship Journal     Open Access   (Followers: 19)
Business & Information Systems Engineering     Hybrid Journal   (Followers: 4)
Business & Society     Hybrid Journal   (Followers: 10)
Business : Theory and Practice / Verslas : Teorija ir Praktika     Open Access   (Followers: 1)
Business and Economic Research     Open Access   (Followers: 7)
Business and Management Horizons     Open Access   (Followers: 12)
Business and Management Research     Open Access   (Followers: 19)
Business and Management Studies     Open Access   (Followers: 11)
Business and Professional Communication Quarterly     Hybrid Journal   (Followers: 6)
Business and Society Review     Hybrid Journal   (Followers: 5)
Business Economics     Hybrid Journal   (Followers: 10)
Business Ethics Quarterly     Full-text available via subscription   (Followers: 13)
Business Ethics: A European Review     Hybrid Journal   (Followers: 18)
Business Horizons     Hybrid Journal   (Followers: 9)
Business Information Review     Hybrid Journal   (Followers: 14)
Business Management and Strategy     Open Access   (Followers: 41)
Business Research     Hybrid Journal   (Followers: 2)
Business Strategy and the Environment     Hybrid Journal   (Followers: 13)
Business Strategy Review     Hybrid Journal   (Followers: 7)
Business Strategy Series     Hybrid Journal   (Followers: 6)
Business Systems & Economics     Open Access   (Followers: 2)
Business Systems Research Journal     Open Access   (Followers: 5)
Business, Management and Education     Open Access   (Followers: 17)
Business, Peace and Sustainable Development     Full-text available via subscription   (Followers: 3)
Business: Theory and Practice     Open Access  
Bustan     Hybrid Journal  
Cadernos EBAPE.BR     Open Access   (Followers: 1)
Cambridge Journal of Economics     Hybrid Journal   (Followers: 62)
Cambridge Journal of Regions, Economy and Society     Hybrid Journal   (Followers: 11)
Canadian Journal of Administrative Sciences / Revue Canadienne des Sciences de l Administration     Hybrid Journal   (Followers: 1)
Canadian Journal of Economics/Revue Canadienne d`Economique     Hybrid Journal   (Followers: 31)
Canadian journal of nonprofit and social economy research     Open Access   (Followers: 3)
Capitalism Nature Socialism     Hybrid Journal   (Followers: 18)
Cappadocia Academic Review     Open Access  
Case Studies in Business and Management     Open Access   (Followers: 10)
CBU International Conference Proceedings     Open Access   (Followers: 3)
Central European Business Review     Open Access   (Followers: 1)
Central European Journal of Operations Research     Hybrid Journal   (Followers: 5)
Central European Journal of Public Policy     Open Access   (Followers: 2)
CESifo Economic Studies     Hybrid Journal   (Followers: 17)
Chain Reaction     Full-text available via subscription  
Challenge     Full-text available via subscription   (Followers: 4)
China & World Economy     Hybrid Journal   (Followers: 16)
China : An International Journal     Full-text available via subscription   (Followers: 18)
China Economic Journal: The Official Journal of the China Center for Economic Research (CCER) at Peking University     Hybrid Journal   (Followers: 12)
China Economic Review     Hybrid Journal   (Followers: 11)
China Finance Review International     Hybrid Journal   (Followers: 5)
China Nonprofit Review     Hybrid Journal   (Followers: 3)
China perspectives     Open Access   (Followers: 12)
Chinese Economy     Full-text available via subscription  
Ciência & Saúde Coletiva     Open Access   (Followers: 2)
Ciencia Sociales y Económicas     Open Access  
CLIO América     Open Access   (Followers: 1)
Cliometrica     Hybrid Journal   (Followers: 4)
COEPTUM     Open Access  
Community Development Journal     Hybrid Journal   (Followers: 27)
Compensation & Benefits Review     Hybrid Journal   (Followers: 7)
Competition & Change     Hybrid Journal   (Followers: 11)
Competitive Intelligence Review     Hybrid Journal   (Followers: 2)
Competitiveness Review : An International Business Journal incorporating Journal of Global Competitiveness     Hybrid Journal   (Followers: 5)
Computational Economics     Hybrid Journal   (Followers: 9)
Computational Mathematics and Modeling     Hybrid Journal   (Followers: 8)
Computer Law & Security Review     Hybrid Journal   (Followers: 17)
Computers & Operations Research     Hybrid Journal   (Followers: 12)
Construction Innovation: Information, Process, Management     Hybrid Journal   (Followers: 14)
Contemporary Wales     Full-text available via subscription   (Followers: 1)
Contributions to Political Economy     Hybrid Journal   (Followers: 5)
Corporate Communications An International Journal     Hybrid Journal   (Followers: 7)
Corporate Philanthropy Report     Hybrid Journal   (Followers: 3)
Corporate Reputation Review     Hybrid Journal   (Followers: 5)
Creative and Knowledge Society     Open Access   (Followers: 9)
Creative Industries Journal     Hybrid Journal   (Followers: 8)
CRIS - Bulletin of the Centre for Research and Interdisciplinary Study     Open Access   (Followers: 1)

        1 2 3 4 5 6 7 | Last

Journal Cover
Biodegradation
Journal Prestige (SJR): 0.876
Citation Impact (citeScore): 2
Number of Followers: 1  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1572-9729 - ISSN (Online) 0923-9820
Published by Springer-Verlag Homepage  [2350 journals]
  • Modulation of microbial consortia enriched from different polluted
           environments during petroleum biodegradation
    • Authors: Rahma Omrani; Giulia Spini; Edoardo Puglisi; Dalila Saidane
      Pages: 187 - 209
      Abstract: Abstract Environmental microbial communities are key players in the bioremediation of hydrocarbon pollutants. Here we assessed changes in bacterial abundance and diversity during the degradation of Tunisian Zarzatine oil by four indigenous bacterial consortia enriched from a petroleum station soil, a refinery reservoir soil, a harbor sediment and seawater. The four consortia were found to efficiently degrade up to 92.0% of total petroleum hydrocarbons after 2 months of incubation. Illumina 16S rRNA gene sequencing revealed that the consortia enriched from soil and sediments were dominated by species belonging to Pseudomonas and Acinetobacter genera, while in the seawater-derived consortia Dietzia, Fusobacterium and Mycoplana emerged as dominant genera. We identified a number of species whose relative abundances bloomed from small to high percentages: Dietzia daqingensis in the seawater microcosms, and three OTUs classified as Acinetobacter venetianus in all two soils and sediment derived microcosms. Functional analyses on degrading genes were conducted by comparing PCR results of the degrading genes alkB, ndoB, cat23, xylA and nidA1 with inferences obtained by PICRUSt analysis of 16S amplicon data: the two data sets were partly in agreement and suggest a relationship between the catabolic genes detected and the rate of biodegradation obtained. The work provides detailed insights about the modulation of bacterial communities involved in petroleum biodegradation and can provide useful information for in situ bioremediation of oil-related pollution.
      PubDate: 2018-04-01
      DOI: 10.1007/s10532-018-9823-3
      Issue No: Vol. 29, No. 2 (2018)
       
  • The effect and biological mechanism of granular sludge size on performance
           of autotrophic nitrogen removal system
    • Authors: Xing Ya-juan; Ji Jun-yuan; Zheng Ping; Wang Lan; Ghulam Abbas; Jiqiang Zhang; Wang Ru; He Zhan-fei
      Abstract: Abstract The autotrophic process for nitrogen removal has attracted worldwide attention in the field of wastewater treatment, and the performance of this process is greatly influenced by the size of granular sludge particles present in the system. In this work, the granular sludge was divided into three groups, i.e. large size (> 1.2 mm), medium size (0.6–1.2 mm) and small size (< 0.6 mm). The medium granular sludge was observed to dominate at high volumetric nitrogen loading rates, while offering strong support for good performance. Its indispensable contribution was found to originate from improved settling velocity (0.84 ± 0.10 cm/s), high SOUR-A (specific oxygen uptake rate for ammonia oxidizing bacteria, 25.93 mg O2/g MLVSS/h), low SOUR-N (specific oxygen uptake rate for nitrite oxidizing bacteria, 3.39 mg O2/g MLVSS/h), and a reasonable microbial spatial distribution.
      PubDate: 2018-05-31
      DOI: 10.1007/s10532-018-9836-y
       
  • Exploring potential applications of a novel extracellular polymeric
           substance synthesizing bacterium ( Bacillus licheniformis ) isolated from
           gut contents of earthworm ( Metaphire posthuma ) in environmental
           remediation
    • Authors: Jayanta Kumar Biswas; Anurupa Banerjee; Mahendra Kumar Rai; Jörg Rinklebe; Sabry M. Shaheen; Santosh Kumar Sarkar; Madhab Chandra Dash; Anilava Kaviraj; Uwe Langer; Hocheol Song; Meththika Vithanage; Monojit Mondal; Nabeel Khan Niazi
      Abstract: Abstract The aim was to isolate, characterize, and explore potentials of gut bacteria from the earthworm (Metaphire posthuma) and imply these bacteria for remediation of Cu(II) and Zn(II). An extracellular polymeric substance (EPS) producing gut bacteria (Bacillus licheniformis strain KX657843) was isolated and identified based on 16S rRNA sequencing and phylogenetic analysis. The strain showed maximum tolerance of 8 and 6 mM for Cu(II) and Zn(II) respectively. It removed 34.5% of Cu(II) and 54.4% of Zn(II) at 25 mg L−1 after 72 and 96 h incubation respectively. The bacteria possessed a great potential to produce indole acetic acid (38.49 μg mL−1) at 5 mg mL−1 l-tryptophan following 12 days incubation. The sterilized seeds of mung beans (Vigna radiata) displayed greater germination and growth under bacterium enriched condition. We observed that the bacterial strain phosphate solubilization ability with a maximum of 204.2 mg L−1 in absence of Cu(II) and Zn(II). Endowed with biosurfactant property the bacterium exhibited 24% emulsification index. The bacterium offered significant potential of plant growth promotion, Cu(II) and Zn(II) removal, and as such this study is the first report on EPS producing B. licheniformis KX657843 from earthworm which can be applied as powerful tool in remediation programs of Cu(II) and Zn(II) contaminated sites.
      PubDate: 2018-05-22
      DOI: 10.1007/s10532-018-9835-z
       
  • Competition for electrons between mono-oxygenations of pyridine and
           2-hydroxypyridine
    • Authors: Chao Yang; Yingxia Tang; Hua Xu; Ning Yan; Naiyu Li; Yongming Zhang; Bruce E. Rittmann
      Abstract: Abstract Pyridine and its heterocyclic derivatives are widely encountered in industrial wastewaters, and they are relatively recalcitrant to biodegradation. Pyridine biodegradation is initiated by two mono-oxygenation reactions that compete for intracellular electron donor (2H). In our experiments, UV photolysis of pyridine generated succinate, whose oxidation augmented the intracellular electron donor and accelerated pyridine biodegradation and mineralization. The first mono-oxygenation reaction always was faster than the second one, because electrons provided by intracellular electron donors were preferentially utilized by the first mono-oxygenase; this was true even when the concentration of 2HP was greater than the concentration of pyridine. In addition, the first mono-oxygenation had faster kinetics because it had higher affinity for its substrate (pyridine), along with less substrate self-inhibition.
      PubDate: 2018-05-21
      DOI: 10.1007/s10532-018-9834-0
       
  • Application of a low-cost biosurfactant in heavy metal remediation
           processes
    • Authors: Rivaldo B. da Rocha Junior; Hugo M. Meira; Darne G. Almeida; Raquel D. Rufino; Juliana M. Luna; Valdemir A. Santos; Leonie A. Sarubbo
      Abstract: Abstract The industrial interest in microbial surfactants has intensified in recent years due to the characteristics of these compounds, such as biodegradability, low toxicity, and effectiveness in removing heavy metals and hydrophobic organic compounds from soil and water. This paper describes the production of a biosurfactant by the yeast Candida tropicalis grown in distilled water with 2.5% molasses, 2.5% frying oil and 4% corn steep liquor. The production of the biosurfactant reached 27 g/l in a 50-l bioreactor with a surface tension of 30 mN/m. Surface tension and engine oil emulsification assays demonstrated the stability of biosurfactant under extreme conditions of temperature and pH as well as in the presence of NaCl. Chemical structures of the biosurfactant were identified using GC–MS and NMR. The isolated biosurfactant was characterised as an anionic molecule capable of reducing the surface tension of water from 70 to 30 mN/m at 0.5% of the critical micelle concentration, with no toxic effects on plant seeds or brine shrimp. In tests involving both the crude and isolated biosurfactant for the removal of heavy metals from contaminated sand under dynamic conditions, the removal rates for Zn and Cu ranged from 30 to 80%, while the best removal rate for Pb was 15%. Tests in packed columns also confirmed the ability of biosurfactant to remove Cu and Zn at rates ranging from 45 to 65%. However, lead was not removed under static conditions. The removal kinetics demonstrated that 30 min was sufficient for the removal of metals and a single washing with the biosurfactant achieved greater removal efficiency. The use of the biosurfactant led to a significant reduction in the electrical conductivity of solutions containing heavy metals. The present findings as well as a brief economic analysis suggest the great potential of this agent for industrial remediation processes of soil and water polluted with inorganic contaminants.
      PubDate: 2018-05-04
      DOI: 10.1007/s10532-018-9833-1
       
  • Production, formulation and cost estimation of a commercial biosurfactant
    • Authors: Rita de Cássia Freire Soares da Silva; Darne Germano de Almeida; Pedro Pinto Ferreira Brasileiro; Raquel Diniz Rufino; Juliana Moura de Luna; Leonie Asfora Sarubbo
      Abstract: Abstract Due to their amphipathic nature, biosurfactants are multifunctional molecules that have considerable potential in several industries, especially the petroleum industry. In this study, the commercial production of a biosurfactant from Pseudomonas cepacia CCT6659 grown on industrial waste was investigated in a semi-industrial 50-L bioreactor for use in the removal of hydrocarbons from oily effluents. A concentration of 40.5 g/L was achieved in the scale up and the surface tension was reduced to 29 mN/m. The biosurfactant was formulated with an added preservative, tyndallization and the combination of fluent vaporization plus the preservative. Formulated biosurfactant samples were stored for 120 days. Tensioactive properties and stability were evaluated with different pH values, temperatures and salt concentrations. The commercial biosurfactant obtained with all formulation methods demonstrated good stability, with tolerance to a wide range of pH values as well as high temperature and high salinity, enabling application in extreme environmental conditions, as it occurs in industrial plants. The biosurfactant proved to be economically viable for large-scale application, as demonstrated by the cost of the product, estimated at around US$ 0.14–0.15/L and US$ 0.02/g for the formulated and the isolated biosurfactant, respectively. Both products were applied in an oil-fired thermoelectric plant for the treatment of oily effluents and removed up to 100% of the oil. Therefore, this biosurfactant is suitable for application under extreme conditions, such as in the petroleum industry, and can be produced at a more attractive price compared to other commercially available products on the market.
      PubDate: 2018-05-03
      DOI: 10.1007/s10532-018-9830-4
       
  • 1,4-Dioxane degradation characteristics of Rhodococcus aetherivorans JCM
           14343
    • Authors: Daisuke Inoue; Tsubasa Tsunoda; Norifumi Yamamoto; Michihiko Ike; Kazunari Sei
      Abstract: Abstract Rhodococcus aetherivorans JCM 14343 can degrade 1,4-dioxane as a sole carbon and energy source. This study aimed to characterize this 1,4-dioxane degradation ability further, and assess the potential use of the strain for 1,4-dioxane removal in industrial wastewater. Strain JCM 14343 was able to degrade 1,4-dioxane inducibly, and its 1,4-dioxane degradation was also induced by tetrahydrofuran and 1,4-butanediol. The demonstration that 1,4-butanediol not only induced but also enhanced 1,4-dioxane degradation was a novel finding of this study. Although strain JCM 14343 appeared not to be an effective 1,4-dioxane degrader considering the maximum specific 1,4-dioxane degradation rate (0.0073 mg-dioxane/mg-protein/h), half saturation concentration (59.2 mg/L), and cell yield (0.031 mg-protein/mg-1,4-dioxane), the strain could degrade over 1100 mg/L of 1,4-dioxane and maintain its degradation activity at a wide range of temperature (5–40 °C) and pH (4–9) conditions. This suggests the usefulness of strain JCM 14343 in 1,4-dioxane treatment under acidic and cold conditions. In addition, 1,4-dioxane degradation experiments in the presence of ethylene glycol (EG) or other cyclic ethers revealed that 1,4-dioxane degradation by strain JCM 14343 was inhibited in the presence of other cyclic ethers, but not by EG, suggesting certain applicability of strain JCM 14343 for industrial wastewater treatment.
      PubDate: 2018-04-25
      DOI: 10.1007/s10532-018-9832-2
       
  • Anthelmintic efficacy of glycolipid biosurfactant produced by Pseudomonas
           plecoglossicida : an insight from mutant and transgenic forms of
           Caenorhabditis elegans
    • Authors: Sabarinathan Devaraj; Mohankumar Amirthalingam; Poorna Chandrika Sabapathy; Shanmugam Govindan; Sundararaj Palanisamy; Preethi Kathirvel
      Abstract: Abstract The current research focuses on the production and characterization of glycolipid biosurfactant (GB) from Pseudomonas plecoglossicida and its anthelmintic activity against Caenorhabditis elegans. The GB was purified and characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography and Mass Spectrometry (GC–MS) analysis. Anthelmintic activity of GB was studied at six different pharmacological doses from 10 to 320 µg/mL on C. elegans. Exposure of different developmental stages (L1, L2, L3, L4 and adult) of C. elegans to the GB reduced the survivability of worms in a dose and time-dependent manner. Adult and L4 worms were least susceptible, while L1, L2 and L3 were more susceptible to GB when compared to the untreated control. An increased exposure period drastically reduced the survival rate of worms and reduction in LC50 value. The GB significantly inhibited the development of C. elegans with an IC50 value of 53.14 µg/mL and even reduced the adult body length and egg hatching. Fecundity rate of the worms treated with GB at 20, 40 and 80 µg/mL decreased from 261.90 ± 3.21 to 239.70 ± 5.58, 164.20 ± 5.94 and 44.80 ± 6.22 eggs per worm, respectively. Besides the toxicological effects, prolonged exposure to GB significantly decreased (p ≤ 0.0001) the lifespan of wild type worms under standard laboratory conditions. Additionally, GB was found to be lethal towards ivermectin and albendazole resistant C. elegans strains. Overall, the data indicated that the GB extracted from P. plecoglossicida could be utilized for the control of non-susceptible and resistant gastrointestinal nematodes towards broad spectrum anthelmintic drugs, ivermectin and albendazole.
      PubDate: 2018-04-16
      DOI: 10.1007/s10532-018-9831-3
       
  • Kinetics study of nicosulfuron degradation by a Pseudomonas nitroreducens
           strain NSA02
    • Authors: Haoyu Zhao; Jianyi Zhu; Shengnan Liu; Xiaogang Zhou
      Abstract: Abstract A bacterial strain NSA02, isolated from contaminated soil and identified as Pseudomonas nitroreducens based on partial 16S rDNA gene sequence analysis and BIOLOG microbiology analysis, was used to study biodegradation of nicosulfuron in the culture medium. The optimal degradation conditions were determined to be 30 °C and pH 7.0. Batch tests were performed for seven different initial substrate concentrations to observe substrate degradation and associated cell growth. The biodegradation kinetics was found to follow a first-order model with regression values greater than 0.98. Specific degradation rate and specific growth rate of bacterial cells were observed to follow substrate inhibition kinetics, and the maximum values of both rates were observed at 100 mg L−1 of nicosulfuron concentration. Kinetic parameters of three substrate inhibition models (Haldane, Aiba–Edwards and Teissier–Edwards) were fitted to the relationship between those rates and substrate concentrations. With the date obtained, Haldane and Teissier–Edwards models provide better representation when compared to Aiba–Edwards model. Inoculating nicosulfuron-treated soil samples with strain NSA02 resulted in a 5–6 times higher rate of nicosulfuron removal than that in non-inoculated soil. Five metabolites of nicosulfuron degradation were detected and identified by liquid chromatography mass spectrometry, and three possible biotransformation pathways were proposed. These results highlight the potential of the isolated bacterium to be used in the bioremediation of nicosulfuron-contaminated soils.
      PubDate: 2018-04-10
      DOI: 10.1007/s10532-018-9828-y
       
  • Nitrogen removal performance and microbial community of an enhanced
           multistage A/O biofilm reactor treating low-strength domestic wastewater
    • Authors: Han Chen; Ang Li; Qiao Wang; Di Cui; Chongwei Cui; Fang Ma
      Abstract: Abstract The low-strength domestic wastewater (LSDW) treatment with low chemical oxygen demand (COD) has drawn extensive attention for the poor total nitrogen (TN) removal performance. In the present study, an enhanced multistage anoxic/oxic (A/O) biofilm reactor was designed to improve the TN removal performance of the LSDW treatment. Efficient nitrifying and denitrifying biofilm carriers were cultivated and then filled into the enhanced biofilm reactor as the sole microbial source. Step-feed strategy and internal recycle were adopted to optimize the substrate distribution and the organics utilization. Key operational parameters were optimized to obtain the best nitrogen and organics removal efficiencies. A hydraulic retention time of 8 h, an influent distribution ratio of 2:1 and an internal recycle ratio of 200% were tested as the optimum parameters. The ammonium, TN and COD removal efficiencies under the optimal operational parameters separately achieved 99.75 ± 0.21, 59.51 ± 1.95 and 85.06 ± 0.79% with an organic loading rate at around 0.36 kg COD/m3 d. The high-throughput sequencing technology confirmed that nitrifying and denitrifying biofilm could maintain functional bacteria in the system during long-period operation. Proteobacteria and Bacteroidetes were the dominant phyla in all the nitrifying and denitrifying biofilm samples. Nitrosomonadaceae_uncultured and Nitrospira sp. stably existed in nitrifying biofilm as the main nitrifiers, while several heterotrophic genera, such as Thauera sp. and Flavobacterium sp., acted as potential genera responsible for TN removal in denitrifying biofilm. These findings suggested that the enhanced biofilm reactor could be a promising route for the treatment of LSDW with a low COD level.
      PubDate: 2018-04-07
      DOI: 10.1007/s10532-018-9829-x
       
  • Biodegradation of pentafluorosulfanyl-substituted aminophenol in
           Pseudomonas spp.
    • Authors: Marta Saccomanno; Sabir Hussain; Neil K. O’Connor; Petr Beier; Mate Somlyay; Robert Konrat; Cormac D. Murphy
      Abstract: Abstract The pentafluorosulfanyl (SF5–) substituent conveys properties that are beneficial to drugs and agrochemicals. As synthetic methodologies improve the number of compounds containing this group will expand and these chemicals may be viewed as emerging pollutants. As many microorganisms can degrade aromatic xenobiotics, we investigated the catabolism of SF5-substituted aminophenols by bacteria and found that some Pseudomonas spp. can utilise these compounds as sole carbon and energy sources. GC–MS analysis of the culture supernatants from cultures grown in 5-(pentafluorosulfanyl) 2-aminophenol demonstrated the presence of the N-acetylated derivative of the starting substrate and 4-(pentafluorosulfanyl)catechol. Biotransformation experiments with re-suspended cells were also conducted and fluorine-19 NMR analyses of the organic extract and aqueous fraction from suspended cell experiments revealed new resonances of SF5-substituted intermediates. Supplementation of suspended cell cultures with yeast extract dramatically improved the degradation of the substrate as well as the release of fluoride ion. 4-(Pentafluorosulfanyl)catechol was shown to be a shunt metabolite and toxic to some of the bacteria. This is the first study to demonstrate that microorganisms can biodegrade SF5-substituted aromatic compounds releasing fluoride ion, and biotransform them generating a toxic metabolite.
      PubDate: 2018-03-30
      DOI: 10.1007/s10532-018-9827-z
       
  • Improvement of sulfamethoxazole (SMX) elimination and inhibition of
           formations of hydroxylamine-SMX and N4-acetyl-SMX by membrane bioreactor
           systems
    • Authors: Min-Hui Tang; Nan Gao; Jiao Zhou; Yan Zhao; Jing-Sheng Cheng; Wen-Kun Su; Ying-Jin Yuan
      Abstract: Abstract Sulfamethoxazole (SMX) has frequently been detected in aquatic environments. In natural environment, not only individual microorganism but also microbial consortia are involved in some biotransformation of pollutants. The competition for space under consortia causing cell–cell contact inhibition changes the cellular behaviors. Herein, the membrane bioreactor system (MBRS) was applied to improve SMX elimination thorough exchanging the cell-free broths (CFB). The removal efficiency of SMX was increased by more than 24% whether under the pure culture of A. faecalis or under the co-culture of A. faecalis and P. denitrificans with MBRS. Meanwhile, MBRS significantly inhibited the formation of HA-SMX, and Ac-SMX from parent compound. Additionally, the cellular growth under MBRS was obviously enhanced, indicating that the increases in the cellular growth under MBRS are possibly related to the decreases in the levels of HA-SMX and Ac-SMX compared to that without MBRS. The intracellular NADH/NAD+ ratios of A. faecalis under MBRS were increased whether thorough itself-recycle of CFB or exchanging CFB between the pure cultures of A. faecalis and P. denitrificans, suggesting that the enhancement in the bioremoval efficiencies of SMX under MBRS by A. faecalis is likely related to the increases in the NADH/NAD+ ratio. Taken together, the regulation of cell-to-cell communication is preferable strategy to improve the bioremoval efficiency of SMX.
      PubDate: 2018-03-15
      DOI: 10.1007/s10532-018-9826-0
       
  • Anaerobic biodegradation of partially hydrolyzed polyacrylamide in
           long-term methanogenic enrichment cultures from production water of oil
           reservoirs
    • Authors: Hao Hu; Jin-Feng Liu; Cai-Yun Li; Shi-Zhong Yang; Ji-Dong Gu; Bo-Zhong Mu
      Abstract: Abstract The increasing usage of partially hydrolyzed polyacrylamide (HPAM) in oilfields as a flooding agent to enhance oil recovery at so large quantities is an ecological hazard to the subsurface ecosystem due to persistence and inertness. Biodegradation of HPAM is a potentially promising strategy for dealing with this problem among many other methods available. To understand the responsible microorganisms and mechanism of HPAM biodegradation under anaerobic conditions, an enrichment culture from production waters of oil reservoirs were established with HPAM as the sole source of carbon and nitrogen incubated for over 328 days, and analyzed using both molecular microbiology and chemical characterization methods. Gel permeation chromatography, High-pressure liquid chromatography and Fourier-transformed infrared spectroscopy results indicated that, after 328 days of anaerobic incubation, some of the amide groups on HPAM were removed and released as ammonia/ammonium and carboxylic groups, while the carbon backbone of HPAM was converted to smaller polymeric fragments, including oligomers and various fatty acids. Based on these results, the biochemical process of anaerobic biodegradation of HPAM was proposed. The phylogenetic analysis of 16S rRNA gene sequences retrieved from the enrichments showed that Proteobacteria and Planctomycetes were the dominant bacteria in the culture with HPAM as the source of carbon and nitrogen, respectively. For archaea, Methanofollis was more abundant in the anaerobic enrichment. These results are helpful for understanding the process of HPAM biodegradation and provide significant insights to the fate of HPAM in subsurface environment and for possible bioremediation.
      PubDate: 2018-03-03
      DOI: 10.1007/s10532-018-9825-1
       
  • Contaminant concentration versus flow velocity: drivers of biodegradation
           and microbial growth in groundwater model systems
    • Authors: Michael Grösbacher; Dominik Eckert; Olaf A. Cirpka; Christian Griebler
      Abstract: Abstract Aromatic hydrocarbons belong to the most abundant contaminants in groundwater systems. They can serve as carbon and energy source for a multitude of indigenous microorganisms. Predictions of contaminant biodegradation and microbial growth in contaminated aquifers are often vague because the parameters of microbial activity in the mathematical models used for predictions are typically derived from batch experiments, which don’t represent conditions in the field. In order to improve our understanding of key drivers of natural attenuation and the accuracy of predictive models, we conducted comparative experiments in batch and sediment flow-through systems with varying concentrations of contaminant in the inflow and flow velocities applying the aerobic Pseudomonas putida strain F1 and the denitrifying Aromatoleum aromaticum strain EbN1. We followed toluene degradation and bacterial growth by measuring toluene and oxygen concentrations and by direct cell counts. In the sediment columns, the total amount of toluene degraded by P. putida F1 increased with increasing source concentration and flow velocity, while toluene removal efficiency gradually decreased. Results point at mass transfer limitation being an important process controlling toluene biodegradation that cannot be assessed with batch experiments. We also observed a decrease in the maximum specific growth rate with increasing source concentration and flow velocity. At low toluene concentrations, the efficiencies in carbon assimilation within the flow-through systems exceeded those in the batch systems. In all column experiments the number of attached cells plateaued after an initial growth phase indicating a specific “carrying capacity” depending on contaminant concentration and flow velocity. Moreover, in all cases, cells attached to the sediment dominated over those in suspension, and toluene degradation was performed practically by attached cells only. The observed effects of varying contaminant inflow concentration and flow velocity on biodegradation could be captured by a reactive-transport model. By monitoring both attached and suspended cells we could quantify the release of new-grown cells from the sediments to the mobile aqueous phase. Studying flow velocity and contaminant concentrations as key drivers of contaminant transformation in sediment flow-through microcosms improves our system understanding and eventually the prediction of microbial biodegradation at contaminated sites.
      PubDate: 2018-02-28
      DOI: 10.1007/s10532-018-9824-2
       
  • Biochemical pathways and enhanced degradation of di- n -octyl phthalate
           (DOP) in sequencing batch reactor (SBR) by Arthrobacter sp. SLG-4 and
           Rhodococcus sp. SLG-6 isolated from activated sludge
    • Authors: Ke Zhang; Yihao Liu; Qiang Chen; Hongbing Luo; Zhanyuan Zhu; Wei Chen; Jia Chen; You Mo
      Abstract: Two bacterial strains designated as Arthrobacter sp. SLG-4 and Rhodococcus sp. SLG-6, capable of utilizing di-n-octyl phthalate (DOP) as sole source of carbon and energy, were isolated from activated sludge. The analysis of DOP degradation intermediates indicated Arthrobacter sp. SLG-4 could completely degrade DOP. Whereas DOP could not be mineralized by Rhodococcus sp. SLG-6 and the final metabolic product was phthalic acid (PA). The proposed DOP degradation pathway by Arthrobacter sp. SLG-4 was that strain SLG-4 initially transformed DOP to PA via de-esterification pathway, and then PA was metabolized to protocatechuate acid and eventually converted to tricarboxylic acid (TCA) cycle through meta-cleavage pathway. Accordingly, Phthalate 3,4-dioxygenase genes (phtA) responsible for PA degradation were successfully detected in Arthrobacter sp. SLG-4 by real-time quantitative PCR (q-PCR). q-PCR analysis demonstrated that the quantity of phthalate 3,4-dioxygenase was positively correlated to DOP degradation in SBRs. Bioaugmentation by inoculating DOP-degrading bacteria effectively shortened the start-up of SBRs and significantly enhanced DOP degradation in bioreactors. More than 91% of DOP (500 mg L−1) was removed in SBR bioaugmented with bacterial consortium, which was double of the control SBR. This study suggests bioaugmentation is an effective and feasible technique for DOP bioremediation in practical engineering. Graphical abstract
      PubDate: 2018-02-15
      DOI: 10.1007/s10532-018-9822-4
       
  • Biodegradation of n -alkanes on oil–seawater interfaces at different
           temperatures and microbial communities associated with the degradation
    • Authors: Synnøve Lofthus; Roman Netzer; Anna S. Lewin; Tonje M. B. Heggeset; Tone Haugen; Odd Gunnar Brakstad
      Abstract: Abstract Oil biodegradation studies have mainly focused on microbial processes in dispersions, not specifically on the interfaces between the oil and the seawater in the dispersions. In this study, a hydrophobic adsorbent system, consisting of Fluortex fabrics, was used to investigate biodegradation of n-alkanes and microbial communities on oil–seawater interfaces in natural non-amended seawater. The study was performed over a temperature range from 0 to 20 °C, to determine how temperature affected biodegradation at the oil–seawater interfaces. Biodegradation of n-alkanes were influenced both by seawater temperature and chain-length. Biotransformation rates of n-alkanes decreased by reduced seawater temperature. Low rate coefficients at a seawater temperature of 0 °C were probably associated with changes in physical–chemical properties of alkanes. The primary bacterial colonization of the interfaces was predominated by the family Oceanospirillaceae at all temperatures, demonstrating the wide temperature range of these hydrocarbonoclastic bacteria. The mesophilic genus Oleibacter was predominant at the seawater temperature of 20 °C, and the psychrophilic genus Oleispira at 5 and 0 °C. Upon completion of n-alkane biotransformation, other oil-degrading and heterotrophic bacteria became abundant, including Piscirickettsiaceae (Cycloclasticus), Colwelliaceae (Colwellia), Altermonadaceae (Altermonas), and Rhodobacteraceae. This is one of a few studies that describe the biodegradation of oil, and the microbial communities associated with the degradation, directly at the oil–seawater interfaces over a large temperature interval.
      PubDate: 2018-02-03
      DOI: 10.1007/s10532-018-9819-z
       
  • Simultaneous nitrification and denitrification with different mixed
           nitrogen loads by a hypothermia aerobic bacterium
    • Authors: Tengxia He; Zhenlun Li; Deti Xie; Quan Sun; Yi Xu; Qing Ye; Jiupai Ni
      Abstract: Abstract Microorganism with simultaneous nitrification and denitrification ability plays a significant role in nitrogen removal process, especially in the eutrophic waters with excessive nitrogen loads. The nitrogen removal capacity of microorganism may suffer from low temperature or nitrite nitrogen source. In this study, a hypothermia aerobic nitrite-denitrifying bacterium, Pseudomonas tolaasii strain Y-11, was selected to determine the simultaneous nitrification and denitrification ability with mixed nitrogen source at 15 °C. The sole nitrogen removal efficiencies of strain Y-11 in simulated wastewater were obtained. After 24 h of incubation at 15 °C, the ammonium nitrogen fell below the detection limit from an initial value of 10.99 mg/L. Approximately 88.0 ± 0.33% of nitrate nitrogen was removed with the initial concentration of 11.78 mg/L and the nitrite nitrogen was not detected with the initial concentration of 10.75 mg/L after 48 h of incubation at 15 °C. Additionally, the simultaneous nitrification and denitrification nitrogen removal ability of P. tolaasii strain Y-11 was evaluated using low concentration of mixed NH4+-N and NO3−–N/NO2−–N (about 5 mg/L-N each) and high concentration of mixed NH4+–N and NO3−–N/NO2−–N (about 100 mg/L-N each). There was no nitrite nitrogen accumulation at the time of evaluation. The results demonstrated that P. tolaasii strain Y-11 had higher simultaneous nitrification and denitrification capacity with low concentration of mixed inorganic nitrogen sources and may be applied in low temperature wastewater treatment.
      PubDate: 2018-01-30
      DOI: 10.1007/s10532-018-9820-6
       
  • Biodegradation of sulfonamides by Shewanella oneidensis MR-1 and
           Shewanella sp. strain MR-4
    • Authors: Fei Mao; Xiaohong Liu; Kang Wu; Chen Zhou; Youbin Si
      Abstract: Abstract Because of extensive sulfonamides application in aquaculture and animal husbandry and the consequent increase in sulfonamides discharged into the environment, strategies to remediate sulfonamide-contaminated environments are essential. In this study, the resistance of Shewanella oneidensis MR-1 and Shewanella sp. strain MR-4 to the sulfonamides sulfapyridine (SPY) and sulfamethoxazole (SMX) were determined, and sulfonamides degradation by these strains was assessed. Shewanella oneidensis MR-1 and Shewanella sp. strain MR-4 were resistant to SPY and SMX concentrations as high as 60 mg/L. After incubation for 5 days, 23.91 ± 1.80 and 23.43 ± 2.98% of SPY and 59.88 ± 1.23 and 63.89 ± 3.09% of SMX contained in the medium were degraded by S. oneidensis MR-1 and Shewanella sp. strain MR-4, respectively. The effects of the initial concentration of the sulfonamides and initial pH of the medium on biodegradation, and the degradation of different sulfonamides were assessed. The products were measured by LC–MS; with SPY as a substrate, 2-AP (2-aminopyridine) was the main stable metabolite, and with SMX as a substrate, 3A5MI (3-amino-5-methyl-isoxazole) was the main stable metabolite. The co-occurrence of 2-AP or 3A5MI and 4-aminobenzenesulfonic acid suggests that the initial step in the biodegradation of the two sulfonamides is S–N bond cleavage. These results suggest that S. oneidensis MR-1 and Shewanella sp. strain MR-4 are potential bacterial resources for biodegrading sulfonamides and therefore bioremediation of sulfonamide-polluted environments.
      PubDate: 2018-01-04
      DOI: 10.1007/s10532-017-9818-5
       
  • Identification of metolachlor mineralizing bacteria in aerobic and
           anaerobic soils using DNA-stable isotope probing
    • Authors: Ramdas G. Kanissery; Allana Welsh; Andres Gomez; Lynn Connor; Gerald K. Sims
      Abstract: Abstract The influence of soil environmental factors such as aeration on the ecology of microorganisms involved in the mineralization and degradation of the popular soil-applied pre-emergent herbicide, metolachlor is unknown. To address this knowledge gap, we utilized DNA-based stable isotope probing (SIP) where soil microcosms were incubated aerobically or anaerobically and received herbicide treatments with unlabeled metolachlor or 13C-metolachlor. Mineralization of metolachlor was confirmed as noted from the evolution of 14CO2 from 14C-metolachlor-treated microcosms and clearly demonstrated the efficient utilization of the herbicide as a carbon source. Terminal restriction fragment length polymorphisms (T-RFLP) bacterial community profiling performed on soil DNA extracts indicated that fragment 307 bp from aerobic soil and 212 bp from anaerobic soil were detected only in the herbicide-treated (both unlabeled metolachlor and 13C-metolachlor) soils when compared to the untreated control microcosms. T-RFLP profiles from the ultracentrifugation fractions illustrated that these individual fragments experienced an increase in relative abundance at a higher buoyant density (BD) in the labeled fractions when compared to the unlabeled herbicide amendment fractions. The shift in BD of individual T-RFLP fragments in the density-resolved fractions suggested the incorporation of 13C from labeled herbicide into the bacterial DNA and enabled the identification of organisms responsible for metolachlor uptake from the soil. Subsequent cloning and 16S rRNA gene sequencing of the 13C-enriched fractions implicated the role of organisms closely related to Bacillus spp. in aerobic mineralization and members of Acidobacteria phylum in anaerobic mineralization of metolachlor in soil.
      PubDate: 2017-12-28
      DOI: 10.1007/s10532-017-9817-6
       
  • Ammonium removal using algae–bacteria consortia: the effect of ammonium
           concentration, algae biomass, and light
    • Authors: Huijun Jia; Qiuyan Yuan
      Abstract: Abstract In this study, the effects of ammonium nitrogen concentration, algae biomass concentration, and light conditions (wavelength and intensity) on the ammonium removal efficiency of algae-bacteria consortia from wastewater were investigated. The results indicated that ammonium concentration and light intensity had a significant impact on nitrification. It was found that the highest ammonia concentration (430 mg N/L) in the influent resulted in the highest ammonia removal rate of 108 ± 3.6 mg N/L/days, which was two times higher than the influent with low ammonia concentration (40 mg N/L). At the lowest light intensity of 1000 Lux, algae biomass concentration, light wavelength, and light cycle did not show a significant effect on the performance of algal–bacterial consortium. Furthermore, the ammonia removal rate was approximately 83 ± 1.0 mg N/L/days, which was up to 40% faster than at the light intensity of 2500 Lux. It was concluded that the algae-bacteria consortia can effectively remove nitrogen from wastewater and the removal performance can be stabilized and enhanced using the low light intensity of 1000 Lux that is also a cost-effective strategy.
      PubDate: 2017-12-13
      DOI: 10.1007/s10532-017-9816-7
       
 
 
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