scholarly journals Biodegradation of Allethrin by a Novel Fungus Fusarium proliferatum Strain CF2, Isolated from Contaminated Soils

2020 ◽  
Vol 8 (4) ◽  
pp. 593 ◽  
Author(s):  
Pankaj Bhatt ◽  
Wenping Zhang ◽  
Ziqiu Lin ◽  
Shimei Pang ◽  
Yaohua Huang ◽  
...  
Keyword(s):  
Microbial Degradation ◽  
Contaminated Soils ◽  
Degradation Kinetics ◽  
Fusarium Proliferatum ◽  
Minimal Salt Medium ◽  
Optimum Conditions ◽  
Uninoculated Control ◽  
High Concentrations ◽  
Continuous Use ◽  
Kinetics Of

Continuous use of allethrin has resulted in heavy environmental contamination and has raised public concern about its impact on human health, yet little is known about the kinetics and microbial degradation of this pesticide. This study reported the degradation kinetics in a novel fungal strain, Fusarium proliferatum CF2, isolated from contaminated agricultural fields. Strain CF2 utilized 50 mg·L−1 of allethrin as the sole carbon source for growth in minimal salt medium and tolerated high concentrations of allethrin of up to 1000 mg·L−1. The optimum degradation conditions for strain CF2 were determined to be a temperature of 26 °C and pH 6.0 using response surface methodology. Under optimum conditions, strain CF2 completely degraded allethrin within 144 hours. The degradation kinetics of allethrin followed first order reaction kinetics. Kinetics analysis showed that its half-life was substantially reduced by 507.1 hours, as compared to the uninoculated control. This study provides new insights into the microbial degradation of allethrin with fungal F. proliferatum CF2.

scholarly journals New Insights into the Microbial Degradation of D-Cyphenothrin in Contaminated Water/Soil Environments

2020 ◽  
Vol 8 (4) ◽  
pp. 473 ◽  
Author(s):  
Yaohua Huang ◽  
Ziqiu Lin ◽  
Wenping Zhang ◽  
Shimei Pang ◽  
Pankaj Bhatt ◽  
...  
Keyword(s):  
Microbial Degradation ◽  
Environmental Contamination ◽  
Contaminated Soils ◽  
Culture Conditions ◽  
Synthetic Pyrethroids ◽  
Biochemical Basis ◽  
Benzenedicarboxylic Acid ◽  
Wide Range ◽  
Intermediate Metabolites ◽  
Uninoculated Control

Persistent use of the insecticide D-cyphenothrin has resulted in heavy environmental contamination and public concern. However, microbial degradation of D-cyphenothrin has never been investigated and the mechanism remains unknown. During this study, for the first time, an efficient D-cyphenothrin-degrading bacterial strain Staphylococcus succinus HLJ-10 was identified. Response surface methodology was successfully employed by using Box-Behnken design to optimize the culture conditions. At optimized conditions, over 90% degradation of D-cyphenothrin (50 mg·L−1) was achieved in a mineral salt medium within 7 d. Kinetics analysis revealed that its half-life was reduced by 61.2 d, in comparison with the uninoculated control. Eight intermediate metabolites were detected in the biodegradation pathway of D-cyphenothrin including cis-D-cyphenothrin, trans-D-cyphenothrin, 3-phenoxybenzaldehyde, α-hydroxy-3-phenoxy-benzeneacetonitrile, trans-2,2-dimethyl-3-propenyl-cyclopropanol, 2,2-dimethyl-3-propenyl-cyclopropionic acid, trans-2,2-dimethyl-3-propenyl-cyclopropionaldehyde, and 1,2-benzenedicarboxylic acid, dipropyl ester. This is the first report about the degradation of D-cyphenothrin through cleavage of carboxylester linkage and diaryl bond. In addition to degradation of D-cyphenothrin, strain HLJ-10 effectively degraded a wide range of synthetic pyrethroids including permethrin, tetramethrin, bifenthrin, allethrin, and chlorempenthrin, which are also widely used insecticides with environmental contamination problems. Bioaugmentation of D-cyphenothrin-contaminated soils with strain HLJ-10 substantially enhanced its degradation and over 72% of D-phenothrin was removed from soils within 40 d. These findings unveil the biochemical basis of a highly efficient D-cyphenothrin-degrading bacterial isolate and provide potent agents for eliminating environmental residues of pyrethroids.

scholarly journals Photocatalytic degradation of reactive black 5 on the surface of tin oxide microrods

2018 ◽  
Vol 16 (5) ◽  
pp. 773-781 ◽  
Author(s):  
Shanza Rauf Khan ◽  
Muhammad Umar Khalid ◽  
Saba Jamil ◽  
Songnan Li ◽  
Aiman Mujahid ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Tin Oxide ◽  
Degradation Kinetics ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Reactive Black 5 ◽  
Unit Cells ◽  
High Concentrations ◽  
Co Precipitation ◽  
Kinetics Of

Abstract A simple co-precipitation technique is proposed for synthesis of tin oxide (SnO2) microrods. Stannous chloride and urea were used during synthesis. X-ray powder diffraction (XRD) analysis revealed that the annealed product consists of SnO2 microrods having tetragonal unit cells, while scanning electron microscopy (SEM) analysis revealed the rod-like morphology of a synthesized product. These synthesized microrods are used as photocatalyst for the degradation of reactive black 5 (RB5). Degradation kinetics of RB5 are monitored under daylight in different concentrations of hydrogen peroxide (H2O2) and catalyst. The percentage of RB5 conversion is also calculated at various concentrations of hydrogen peroxide and catalyst which demonstrate that RB5 shows high catalytic degradation at high concentrations of hydrogen peroxide and catalyst.

Study of kinetics of degradation of cyclohexane carboxylic acid by acclimated activated sludge

2016 ◽  
Vol 73 (10) ◽  
pp. 2552-2558 ◽  
Author(s):  
Chunhua Wang ◽  
Shuian Shi ◽  
Hongyan Chen
Keyword(s):  
Carboxylic Acid ◽  
Activated Sludge ◽  
Degradation Kinetics ◽  
Experimental Conditions ◽  
First Order Kinetics ◽  
Effects Of Ph ◽  
High Concentrations ◽  
Cyclohexane Carboxylic Acid ◽  
Kinetics Of ◽  
Acclimated Activated Sludge

Activated sludge contains complex microorganisms, which are highly effective biodegrading agents. In this study, the kinetics of biodegradation of cyclohexane carboxylic acid (CHCA) by an acclimated aerobic activated sludge were investigated. The results showed that after 180 days of acclimation, the activated sludge could steadily degrade >90% of the CHCA in 120 h. The degradation of CHCA by the acclimated activated sludge could be modeled using a first-order kinetics equation. The equations for the degradation kinetics for different initial CHCA concentrations were also obtained. The kinetics constant, kd, decreased with an increase in the CHCA concentration, indicating that, at high concentrations, CHCA had an inhibiting effect on the microorganisms in the activated sludge. The effects of pH on the degradation kinetics of CHCA were also investigated. The results showed that a pH of 10 afforded the highest degradation rate, indicating that basic conditions significantly promoted the degradation of CHCA. Moreover, it was found that the degradation efficiency for CHCA increased with an increase in temperature and concentration of dissolved oxygen under the experimental conditions.

Removal of Acid Yellow 17 Dye by Fenton Oxidation Process

2018 ◽  
Vol 0 (0) ◽  
Author(s):  
Jehangeer Khan ◽  
Murtaza Sayed ◽  
Fayaz Ali ◽  
Hasan Mahmood Khan
Keyword(s):  
Ph Value ◽  
Degradation Kinetics ◽  
Research Work ◽  
Degradation Process ◽  
Optimum Conditions ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Degradation Reaction ◽  
Fenton Oxidation Process ◽  
Kinetics Of

Abstract In the present research work the degradation of acid yellow 17 (AY 17) by H2O2/Fe2+ was investigated. The effect of various conditions such as pH value, temperature, conc. of H2O2, Fe2+, conc. of AY 17 were studied. Additionally the scavenging effects of various anions such as Cl−, SO42−, CO32− and HCO3−, on percent degradation of AY 17 were examined. It was found that these anions decrease percent degradation as well as rate of degradation reaction. The optimum conditions were determined as [AY 17]=[Fe2+]=0.06 mM [H2O2]=0.9 mM, and pH 3.0 for 60 min of reaction time. It was found that at optimum conditions 89% degradation of AY17 was achieved. The degradation kinetics of AY17 followed pseudo-first-order reaction kinetics. Thermodynamic studies under natural conditions showed positive value of ∆H (enthalpy) which indicates the degradation process is endothermic.

Microbial degradation kinetics of solid alkane dissolved in nondegradable oil phase

1999 ◽  
Vol 3 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Dong Hyuk Choi ◽  
Katsutoshi Hori ◽  
Yasunori Tanji ◽  
Hajime Unno
Keyword(s):  
Microbial Degradation ◽  
Degradation Kinetics ◽  
Kinetics Of

scholarly journals Characterization of deltamethrin degradation and metabolic pathway by co-culture of Acinetobacter junii LH-1-1 and Klebsiella pneumoniae BPBA052

2020 ◽  
Author(s):  
Jie Tang ◽  
Qiong Hu ◽  
Dan Lei ◽  
Min Wu ◽  
Chaoyi Zeng ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Contaminated Soils ◽  
Degradation Kinetics ◽  
Degradation Pathway ◽  
Gas Chromatography Mass Spectrometry ◽  
Acinetobacter Junii ◽  
Pyrethroid Pesticides ◽  
First Time ◽  
Kinetics Of

Abstract Deltamethrin and its major metabolite 3-phenoxybenzoic acid (3‐PBA) have caused serious threat to the environment as well as human health, yet little is known about their degradation pathways by bacterial co-cultures. In this study, the growth and degradation kinetics of Acinetobacter junii LH-1-1 and Klebsiella pneumoniae BPBA052 during deltamethrin and 3-PBA degradation were established, respectively. When the inoculum proportion of the strains LH-1-1 and BPBA052 was 7.5:2.5, and LH-1-1 was inoculated 24 h before inoculation of strain BPBA052, 94.25% deltamethrin was degraded and 9.16 mg/L of 3-PBA remained within 72 h, which was 20.36% higher and 10.25 mg/L lesser than that in monoculture of LH-1-1, respectively. And the half-life of deltamethrin was shortened from 38.40 h to 24.58 h. Based on gas chromatography–mass spectrometry, 3-phenoxybenzaldehyde, 1,2-benzenedicarboxylic butyl dacyl ester, and phenol were identified as metabolites during deltamethrin degradation in co-culture. This is the first time that a co-culture degradation pathway of deltamethrin has been proposed based on these identified metabolites. Bioremediation of deltamethrin-contaminated soils with co-culture of strains LH-1-1 and BPBA052 significantly enhanced deltamethrin degradation and 3-PBA removal. This study provides a platform for further studies on deltamethrin and 3-PBA biodegradation mechanism in co-culture, and it also proposes a promising approach for efficient bioremediation of environment contaminated by pyrethroid pesticides and their associated metabolites.

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