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Biodegradation of cyanide under alkaline conditions by a strain of pseudomonas putida isolated from gold mine soil and optimization of process variables through response surface methodology (RSM)
, Article Periodica Polytechnica Chemical Engineering ; Volume 62, Issue 3 , May , 2018 , Pages 265-273 ; 03245853 (ISSN) ; Yaghmaei, S ; Ghobadi Nejad, Z ; Sharif University of Technology
Budapest University of Technology and Economics
2018
Abstract
In regard to highly poisonous effects of cyanide ion, concerns have been focused recently on treatment of such compounds in different ways. Four bacterial strains (C1-C4) capable of using cyanide as nitrogen source were isolated from contaminated gold mine soil samples under alkaline conditions at 30 °C, pH 9.5-10.5, and agitation speed 150 rpm. The gram-negative bacterium C3 (identified as Pseudomonas parafulva NBRC 16636(T) by 16S rRNA gene sequencing) was able to tolerate cyanide up to 500 ppm besides removing 93.5% of 200 ppm cyanide in 13 days which was confirmed by microorganisms growth. The addition of basal salts enhanced the removal efficiency of C3 by 16%. Cyanide removal...
Biodegradation of polychlorinated biphenyls by lysinibacillus macrolides and bacillus firmus isolated from contaminated soil
, Article International Journal of Engineering, Transactions B: Applications ; Volume 32, Issue 5 , 2019 , Pages 628-633 ; 1728144X (ISSN) ; Sharifi, H ; Ghobadi Nejad, Z ; Yaghmaei, S ; Sharif University of Technology
Materials and Energy Research Center
2019
Abstract
Polychlorinated biphenyls (PCBs) cause many significant ecological problems because of their low degradability, high harmfulness, and solid bioaccumulation.Two bacterial strains were isolated from soil that had been polluted with electrical transformer liquid for more than 40 years. The isolates were distinguished as Lysinibacillus macrolides DSM54Tand Bacillus firmus NBRC15306Tthrough 16S rRNA sequencing analysis.This is the primary report of an agent of the genus Bacillus firmus equipped for the removal of PCBs. The strains could develop broadly on 2-Chlorobiphenyl and 2,4-dichlorobiphenyl. GC/MS analysis of individual congeners revealed up to 80% degradation of the xenobiotics in 96h,...
Construction of porous calcite structure using microbially induced calcite precipitation
, Article Journal of Petroleum Science and Engineering ; Volume 217 , 2022 ; 09204105 (ISSN) ; Bazargan, M ; Ghobadi Nejad, Z ; Yaghmaei, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Sporosarcina pasteurii is a well-known ureolytic bacteria that promotes the microbially induced calcite precipitation (MICP) process for several environmental and engineering purposes. In our work, for the first time, MICP has been implemented to form pure, porous calcite structures. The maximum urease activity of S. pasteurii was 1.91 mM urea hydrolyzed min−1 at the late-exponentially phase. A reactor has been designed to achieve semi-continuous treatments, and reagents were introduced to it by a peristaltic pump. A new alternating injection pattern was adopted to obtain well-distributed precipitation. SEM images of treated structures indicated the shapes of CaCO3 crystals at a microscale...
Immobilization of laccase from trametes hirsuta onto CMC coated magnetic nanoparticles
, Article International Journal of Engineering, Transactions A: Basics ; Volume 33, Issue 4 , 2020 , Pages 513-519 ; Ghazvini, S ; Hejazi, S ; Yaghmaei, S ; Ghobadi Nejad, Z ; Sharif University of Technology
Materials and Energy Research Center
2020
Abstract
In this study Fe3O4/CMC magnetic nanoparticles were synthesized through co-precipitation method. Afterward, laccase from Trametes hirsuta was immobilized onto Carboxymethyl cellulose (CMC)-coated magnetic Fe3O4 nanoparticles by covalent bonding between carboxyl groups of carboxymethyl cellulose and amine group of laccases. Also, the resulted magnetic nanoparticles and immobilized laccase were characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and dynamic light scattering (DLS) analysis. Moreover, the vital factors in enzyme immobilization, such as contact time, amount of N-hydroxysuccinimide (NHS), and the amount of nanoparticles were...
Study potential of indigenous pseudomonas aeruginosa and bacillus subtilis in bioremediation of diesel-contaminated water
, Article Water, Air, and Soil Pollution ; Volume 228, Issue 1 , 2017 ; 00496979 (ISSN) ; Kariminia, H. R ; Ghobadi Nejad, Z ; Fletcher, T. H ; Sharif University of Technology
2017
Abstract
Petroleum products which are used in a wide variety of industries as energy sources and raw materials have become a major concern in pollution of terrestrial and marine environments. The purpose of this study was to assess the potential of indigenous microbial isolates for degradation of diesel fuel. Two most proficient bacterial strains among five isolated strains from polluted soil of an industrial refinery were studied. The isolates then were identified as Pseudomonas aeruginosa and Bacillus subtilis using biochemical tests and 16S rRNA gene sequence analyses. P. aeruginosa showed higher biodegradation efficiency than B. subtilis in shaking flask containing diesel-contaminated water. P....
Biodegradation of 4-chlorobenzoic acid by lysinibacillus macrolides DSM54T and determination of optimal conditions
, Article International Journal of Environmental Research ; Volume 14, Issue 2 , 2020 , Pages 145-154 ; Sharifi, H ; Ghobadi Nejad, Z ; Hasan Zadeh, A ; Yaghmaei, S ; Sharif University of Technology
Springer
2020
Abstract
Chlorobenzoic acids (CBAs) are recalcitrant and toxic materials which enter the environment directly using pesticides and herbicides, or indirectly through the biodegradation of polychlorinated biphenyl (PCB) compounds. In the conducted study, biodegradation of 4-chlrobenzoic acid was investigated by Lysinibacillus macrolides DSM54T, which had previously been isolated from PCB-polluted soils. Environmental factors including pH, temperature, 4-CBA concentration and inoculation percentage were optimized using response surface methodology (RSM). 58 experiments were designed according to Historical Data, because of the arbitrary selection of experiments, and the combined effects of the...
Pharmaceuticals removal by immobilized laccase on polyvinylidene fluoride nanocomposite with multi-walled carbon nanotubes
, Article Chemosphere ; Volume 263 , 2021 ; 00456535 (ISSN) ; Golgoli, M ; Ghobadi Nejad, Z ; Sadeghzadeh, S ; Borghei, S. M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
The presence of pharmaceutical micropollutants in water and wastewater is considered a serious environmental issue. To eliminate these pollutants, biodegradation of pharmaceuticals using enzymes such as laccase, is proposed as a green method. In this study, immobilized laccase was used for the removal of two model pharmaceutical compounds, carbamazepine and diclofenac. Polyvinylidene fluoride (PVDF) membrane modified with multi-walled carbon nanotubes (MWCNTs) were synthesized as a tailor-made support for enzyme immobilization. Covalently immobilized laccase from Trametes hirsuta exhibited remarkable activity and activity recovery of 4.47 U/cm2 and 38.31%, respectively. The results also...
Improvement of the microfluidic microbial fuel cell using a nickel nanostructured electrode and microchannel modifications
, Article Journal of Power Sources ; Volume 437 , 2019 ; 03787753 (ISSN) ; Ghasemi, S ; Sanaee, Z ; Ghobadi Nejad, Z ; Mardanpour, M. M ; Yaghmaei, S ; Ghorbanzadeh, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, the effect of utilization of a nanostructured nickel based material as a negative electrode on the performance of microfluidic microbial fuel cell (MFC) with Escherichia coli as biocatalyst has been investigated. Designing the microfluidic MFC with nickel nanostructure resulted in a higher volumetric power density of 343 W m−3 compared to the previously published results. The assessment of effective parameters on the electrochemical performance of cell was investigated. The investigation of the hydraulic diameter impact on the power generation proves that reducing the microchannel hydraulic diameter from 1000 to 350 μm minimized the internal mass-transfer resistance, and...
Production of extracellular protease and determination of optimal condition by bacillus licheniformis BBRC 100053
, Article International Journal of Engineering, Transactions B: Applications ; Volume 22, Issue 3 , 2009 , Pages 221-228 ; 1728-144X (ISSN) ; Yaghmaei, S ; Haji Hosseini, R ; Sharif University of Technology
Materials and Energy Research Center
2009
Abstract
The production of protease by Bacillus licheniformis BBRC 100053 was studied. The most appropriate medium for the growth and protease production is composed of: lactose 1%, yeast extract 0.5%, peptone 0.5%, KH2 PO 4 0.1%, MgSO4 .7H2 O 0.02%. Enzyme production corresponded with growth and reached a maximums level (589 U/ml) during the stationary phase at 35°C, pH equivalent to 10 and with 150 rpm after 73 hours. Protease activity was highest at pH 8 and 45°C. The best carbon sources are respectively lactose and maltose and the best nitrogen source is peptone. The protease was highly active and stable from pH 7.0 to 11.0 with an optimum at pH 7-8....
Biodegradation of synthetic dye using partially purified and characterized laccase and its proposed mechanism
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 12 , 2019 , Pages 7805-7816 ; 17351472 (ISSN) ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
The supernatant obtained from the extracellular laccase produced by Phanerochaete chrysosporium was used as the enzyme source to conduct a partial purification, characterization and dye decolorization study. The partially purified enzyme was stable in the pH range of 3–5 and showed an optimum activity at pH 4.0, using guaiacol as a substrate. Laccase stability of pH was determined and discovered to retain 100% of its activity at a pH of 4.0 after 2 h. The maximum enzyme activity was obtained between 30 and 50 °C. The maximum velocity and Michaelis constant were calculated as 3.171 µM−1·min and 1628.23 µM, respectively. The enzyme was activated by Fe2+, Zn2+, Ca2+ and Cu2+, while Hg2+, Mn2+,...
Kinetic studies of Bisphenol A in aqueous solutions by enzymatic treatment
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 2 , 2019 , Pages 821-832 ; 17351472 (ISSN) ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
Bisphenol A (BPA), which is a major component in the production of various consumer products, is one of the most significant endocrine-disrupting chemicals. In this research, the biocatalytic elimination of Bisphenol A using laccase produced by Phanerochaete chrysosporium was examined and optimized. The response surface methodology was used to study the effect of independent variables such as pH, temperature, initial laccase activity, initial Bisphenol A concentration, and the interactive effects of each variable on the removal of Bisphenol A and residual enzyme activity. Based on response surface plots, the maximum Bisphenol A removal (93%) was detected at a pH value of 8, temperature...
Kinetic studies of Bisphenol A in aqueous solutions by enzymatic treatment
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 2 , Febraury , 2018 , Pages 821–832 ; 17351472 (ISSN) ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2018
Abstract
Bisphenol A (BPA), which is a major component in the production of various consumer products, is one of the most significant endocrine-disrupting chemicals. In this research, the biocatalytic elimination of Bisphenol A using laccase produced by Phanerochaete chrysosporium was examined and optimized. The response surface methodology was used to study the effect of independent variables such as pH, temperature, initial laccase activity, initial Bisphenol A concentration, and the interactive effects of each variable on the removal of Bisphenol A and residual enzyme activity. Based on response surface plots, the maximum Bisphenol A removal (93%) was detected at a pH value of 8, temperature 40...
Some investigations on protease enzyme production kinetics using bacillus licheniformis BBRC 100053 and effects of inhibitors on protease activity
, Article International Journal of Chemical Engineering ; 2014 ; ISSN: 1687806X ; Yaghmaei, S ; Moghadam, N ; Sadeghein, B ; Sharif University of Technology
2014
Abstract
Due to great commercial application of protease, it is necessary to study kinetic characterization of this enzyme in order to improve design of enzymatic reactors. In this study, mathematical modeling of protease enzyme production kinetics which is derived from Bacillus licheniformis BBRC 100053 was studied (at 37°C, pH 10 after 73 h in stationary phase, and 150 rpm). The aim of the present paper was to determine the best kinetic model and kinetic parameters for production of protease and calculating K i (inhibition constant) of different inhibitors to find the most effective one. The kinetic parameters K m (Michaelis-Menten constant) and V m (maximum rate) were calculated 0.626 mM and...
Removal of Pharmaceuticals from Polluted Water Using Carbon Nanotube-based Membranes Coated with Enzyme
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
Abstract
Today, presence of micropollutants, including pharmaceutical compounds, in aquatic systems has turned into a major environmental challenge threatening the health of humans and many aquatic and terrestrial organisms. In the recent years, biodegradation of pharmaceuticals using enzymes, such as laccase, has been presented as a green method for eliminating these types of pollutants. Furthermore, regarding the improved stability and reusability of immobilized enzymes, these types of biocatalysts are suitable for industrial applications. Enzymatic membrane reactor is a promising method of enzymatic treatment and fabrication of a high-efficiency enzymatic membrane is a major step to begin this...
Biodegradation of effluents from dairy plant by bacterial isolates
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 26, Issue 1 , 2007 , Pages 55-59 ; 10219986 (ISSN) ; Samadi, A ; Ghobadi, Z ; Sharif University of Technology
2007
Abstract
Micro flora of the effluents from a dairy factory in Tehran(Pegah Dairy Processing Plant) were isolated and screened for their ability to reduce the organic matter content and COD of the effluents. 10 bacteria were selected due to reduction in COD content from the 4th to 6th day of incubation at 30 °C and pH =11. Highest COD reduction were obtained by two isolates, BP3 and BP4, 70.7 % and 69.5 %, respectively (The initial COD concentration was 3000 mg/l and reduced to 880 and 920 mg/l).After optimization of the condition for test organisms, big reductions in COD, carbohydrate, fat and protein content of the effluents were observed by BP3 up to 84.70 %, 98 %, 45.30 % and 53 %, respectively...
Pharmaceutical Active Compounds Removal by Immobilized Laccase on the Membrane
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
Abstract
Pharmaceutical active compounds existence in the water would cause serious ecological risks and human health-related adverse effects which turn to environmental concern, therefore several studies have done to remove pharmaceutical active compounds efficiently. Carbamazepine (CBZ), a widely used psychiatric drug, is one of the most frequently detected compounds in the surface water and groundwater which is studies in the current study. Recently, biocatalytic degradation using ligninolytic enzymes such as laccase provides a promising approach for their removal from water and wastewater. In this work, carbamazepine removal by immobilized laccase on modified membrane by multi wall carbon nanotube...
Bioremediation of Polychlorinated Biphenyls Contaminated Soils (with Emphasis on 4-chlorobenzoic acid) by Slurry Systems
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
Abstract
Polychlorobiphenyl compounds are a class of persistent organic pollutants consisting of two biphenyl rings and chlorine substations. Polychlorobiphenyls do not dissolve in water, are very stable at high temperatures, and are considered a good conductor. Due to the mentioned properties in the 1930s and 1940s, these compounds were widely used in various industries such as power plants, Painting industry, Plastics industry, etc. After years of use, these substances have been found to be very dangerous to the health of living organisms and the environment due to their high resistance to decomposition and the ability to accumulate in adipose tissue. Today, although the production and use of these...
Removal of Micropollutants using the Combination of Advanced Oxidation Process and Bioreactor
, M.Sc. Thesis Sharif University of Technology ; Ghasemian, Saloumeh (Supervisor) ; Ghobadi Nejad, Zahra (Supervisor)
Abstract
Micropollutants are a wide group of organic compounds that are detected in most compartments of the environment. Their environmental concentration is usually in the range of few ng/l to mg/l, but they remain biologically active even at such low concentrations; may be accumulated through the food chain, and pose a serious threat to the environment, fauna, and human health. Among micropollutants, pharmaceutical active compounds (PhACs) are of special concern. It is accepted that the main sources of PhACs in the environment are effluents from wastewater treatment plants (WWTPs), where conventional activated sludge processes are not able to degrade most of them. To address these concerns, the...
Treatment of Triclosan Through Enhanced Microbial Biodegradation
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Supervisor)
Abstract
Triclosan is widely used as an antibacterial agent in personal health care products, especially in recent years with the spread of the Coronavirus. This substance is one of the emerging contaminants, and due to its stable and toxic nature, this material cannot be destroyed in the process of biological wastewater treatment. In this research, a new bacterial strain was isolated and purified from industrial wastewater for the biological removal of triclosan. Based on 16S rRNA sequencing, it was found that the isolated strain belongs to the Enterobacter cloacae family and can grow in high concentrations of triclosan. It was observed that naphthalene dioxygenase and laccase enzymes are active...
Studying of Laccase Immobilization on Nanoparticles for Bisphenol A Removal
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
Abstract
Bisphenol A is one of Endocrine Disturbing Chemicals. Enzymatic removal of bisphenol A is an interesting and green method. However, application of enzymes has been hampered due to lower operational stability and lots of difficulties in recovery and recycling. Enzyme immobilization can ba an innovative approach to circumvent these drawbacks. Laccase from Trametes hirsuta used for Bisphenol A removal. Firstly, magnetic nanoparticles were synthesized by coprecipitation method and aminofunctionalized by (3-aminopropyl)-mmethoxysilane. Subsequently, laccase was precipitated with i-propanol in the presence of aminofunctionalized nanoparticles and followed by addition of glutaraldehyde to the final...