The effects (stimulatory/inhibitory) of two representative microelements, zinc and copper, on the... more The effects (stimulatory/inhibitory) of two representative microelements, zinc and copper, on the aerobic co-metabolic removal of trichloroethylene (10 mg/L) by the indigenous isolate Pseudomonas plecoglossicida were investigated. The strain was previously isolated from a petroleum contaminated site using toluene (150 mg/L) as growth substrate. Different concentrations (1, 10, and 100 mg/L) of microelements provided with SO42- and Cl- as the anions were tested. The results showed the supplement of Zn2+ and Cu2+ at the low concentration (1 mg/L) significantly enhanced cell growth. The removal efficiencies for toluene and trichloroethylene were also enhanced at the low concentration (1 mg/L) of Zn2+ and Cu2+, compared to the higher concentrations (10 and 100 mg/L). Compared to the control without zinc supplement, higher concentrations of zinc (10 and 100 mg/L) enhanced the removal efficiencies for both toluene and trichloroethylene in the first 3 days but showed some inhibitory effect afterward. However, the higher concentrations of Cu2+ (10 and 100 mg/L) always showed inhibitory to the toluene removal while showing inhibitory to the TCE removal after 3 days. For both Zn2+ and Cu2+, the anions SO42- and Cl- did not show significant difference in their effects on the toluene removal. A possible mechanism for Zn2+ and Cu2+ to enhance the removal of toluene and trichloroethylene would be their involvement in toluene oxygenase-based transformation processes. In addition, high concentrations of Zn2+ and Cu2+ ions could be removed from the liquid by the cells accordingly. The results imply a great potential of supplementing low concentrations of zinc and copper to enhance bioremediation of the sites co-contaminated with toluene and trichloroethylene.
Environmental Progress & Sustainable Energy, 2020
Exploration of eco‐friendly energy resources substituting conventional fossil fuels is the real c... more Exploration of eco‐friendly energy resources substituting conventional fossil fuels is the real challenge globally. Prospectively, current investigation accentuates the fermentative conversion of low‐cost lignocellulosic biomass waste, sugarcane bagasse (SCB) into bioethanol and biohydrogen exploiting thermophilic cellulolytic bacterium Clostridium thermocellum DSMZ 1313. Initially, the optimization of some key fermentation factors for bioethanol and biohydrogen productions was done in 150 ml serum bottles employing Taguchi orthogonal array L27 (3̂13) experimental design. Results elucidated that the most suitable factors for ethanologenesis were 70 g/L cellulose, 10 g/L corn‐steep liquor (CSL), 15 mg/L ferrous sulfate (FeSO4·6H2O), 1 g/L magnesium chloride (MgCl2·6H2O), pH 7, and 5 days incubation whereas for hydrogen fermentation were 60 g/L cellulose, 30 g/L CSL, 5 mg/L FeSO4·6H2O, 2 g/L MgCl2·6H2O, pH 7, and 3 days incubation. Quantitatively, 7.422 g/L ethanol and 56.891/50 ml hy...
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.], 2010
Three bacterial strains J1, J2, J3 which could use pyrene as the sole carbon and energy sources w... more Three bacterial strains J1, J2, J3 which could use pyrene as the sole carbon and energy sources were isolated from soils contaminated with polycyclic aromatic hydrocarbons (PAHs) by enrichment culture. The strains were identified as Pseudomonas aeruginosa, Flavobacterium mizutaii, Brevibacillus parabrevis according to the results of morphology, physiology and the phylogenetical analyses of 16S rDNA sequence. It was observed that the three strains could use pyrene at the concentrations of 50, 100, 200, 500, 1 000 mg/L and after 7 days culture the concentrations of microorganisms in the liquid medium were the highest. Under the treatment of 200 mg/L pyrene the degradation rate of pyrene by strain J1, J2, J3 was 53.04%, 65.03%, 51.02%. The three strains could grow and use pyrene at the culture medium pH 4 to pH 9 and the pH 7 was the best for the microbe growth and the degradation. Compare with the dichloromethane, N, N-dimethylformamide which could increase the solution of pyrene and ...
IOP Conference Series: Earth and Environmental Science
Triclosan (TCS), one of the most widely used antimicrobial agents, is frequently detected at wast... more Triclosan (TCS), one of the most widely used antimicrobial agents, is frequently detected at wastewater treatment plants and environmental matrices including soil, water, sediment, and biota samples. In this study, a TCS-degrading bacterium was isolated from local activated sludge and identified as Burkholderia sp. L303. Strain L303 could degrade TCS (0.5-8 mg/L) as sole carbon source. The optimal condition was 35°C and pH 7. The in-vitro assay with the glucose-enriched cells showed the ability of TCS degradation in real water samples, indicating the functional enzyme expressed in the absence of TCS. The bioaugmentation of strain L303 in non-sterile wastewater showed better degradation rate than that in the control groups. The community profiles showed the potential cooperative interactions between strain L303 and indigenous bacteria, thereby enhancing the TCS degradation in the real polluted water. The finding of this study could facilitate in developing appropriate bioaugmentation...
The effects (stimulatory/inhibitory) of two representative microelements, zinc and copper, on the... more The effects (stimulatory/inhibitory) of two representative microelements, zinc and copper, on the aerobic co-metabolic removal of trichloroethylene (10 mg/L) by the indigenous isolate Pseudomonas plecoglossicida were investigated. The strain was previously isolated from a petroleum contaminated site using toluene (150 mg/L) as growth substrate. Different concentrations (1, 10, and 100 mg/L) of microelements provided with SO42- and Cl- as the anions were tested. The results showed the supplement of Zn2+ and Cu2+ at the low concentration (1 mg/L) significantly enhanced cell growth. The removal efficiencies for toluene and trichloroethylene were also enhanced at the low concentration (1 mg/L) of Zn2+ and Cu2+, compared to the higher concentrations (10 and 100 mg/L). Compared to the control without zinc supplement, higher concentrations of zinc (10 and 100 mg/L) enhanced the removal efficiencies for both toluene and trichloroethylene in the first 3 days but showed some inhibitory effect afterward. However, the higher concentrations of Cu2+ (10 and 100 mg/L) always showed inhibitory to the toluene removal while showing inhibitory to the TCE removal after 3 days. For both Zn2+ and Cu2+, the anions SO42- and Cl- did not show significant difference in their effects on the toluene removal. A possible mechanism for Zn2+ and Cu2+ to enhance the removal of toluene and trichloroethylene would be their involvement in toluene oxygenase-based transformation processes. In addition, high concentrations of Zn2+ and Cu2+ ions could be removed from the liquid by the cells accordingly. The results imply a great potential of supplementing low concentrations of zinc and copper to enhance bioremediation of the sites co-contaminated with toluene and trichloroethylene.
Environmental Progress & Sustainable Energy, 2020
Exploration of eco‐friendly energy resources substituting conventional fossil fuels is the real c... more Exploration of eco‐friendly energy resources substituting conventional fossil fuels is the real challenge globally. Prospectively, current investigation accentuates the fermentative conversion of low‐cost lignocellulosic biomass waste, sugarcane bagasse (SCB) into bioethanol and biohydrogen exploiting thermophilic cellulolytic bacterium Clostridium thermocellum DSMZ 1313. Initially, the optimization of some key fermentation factors for bioethanol and biohydrogen productions was done in 150 ml serum bottles employing Taguchi orthogonal array L27 (3̂13) experimental design. Results elucidated that the most suitable factors for ethanologenesis were 70 g/L cellulose, 10 g/L corn‐steep liquor (CSL), 15 mg/L ferrous sulfate (FeSO4·6H2O), 1 g/L magnesium chloride (MgCl2·6H2O), pH 7, and 5 days incubation whereas for hydrogen fermentation were 60 g/L cellulose, 30 g/L CSL, 5 mg/L FeSO4·6H2O, 2 g/L MgCl2·6H2O, pH 7, and 3 days incubation. Quantitatively, 7.422 g/L ethanol and 56.891/50 ml hy...
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.], 2010
Three bacterial strains J1, J2, J3 which could use pyrene as the sole carbon and energy sources w... more Three bacterial strains J1, J2, J3 which could use pyrene as the sole carbon and energy sources were isolated from soils contaminated with polycyclic aromatic hydrocarbons (PAHs) by enrichment culture. The strains were identified as Pseudomonas aeruginosa, Flavobacterium mizutaii, Brevibacillus parabrevis according to the results of morphology, physiology and the phylogenetical analyses of 16S rDNA sequence. It was observed that the three strains could use pyrene at the concentrations of 50, 100, 200, 500, 1 000 mg/L and after 7 days culture the concentrations of microorganisms in the liquid medium were the highest. Under the treatment of 200 mg/L pyrene the degradation rate of pyrene by strain J1, J2, J3 was 53.04%, 65.03%, 51.02%. The three strains could grow and use pyrene at the culture medium pH 4 to pH 9 and the pH 7 was the best for the microbe growth and the degradation. Compare with the dichloromethane, N, N-dimethylformamide which could increase the solution of pyrene and ...
IOP Conference Series: Earth and Environmental Science
Triclosan (TCS), one of the most widely used antimicrobial agents, is frequently detected at wast... more Triclosan (TCS), one of the most widely used antimicrobial agents, is frequently detected at wastewater treatment plants and environmental matrices including soil, water, sediment, and biota samples. In this study, a TCS-degrading bacterium was isolated from local activated sludge and identified as Burkholderia sp. L303. Strain L303 could degrade TCS (0.5-8 mg/L) as sole carbon source. The optimal condition was 35°C and pH 7. The in-vitro assay with the glucose-enriched cells showed the ability of TCS degradation in real water samples, indicating the functional enzyme expressed in the absence of TCS. The bioaugmentation of strain L303 in non-sterile wastewater showed better degradation rate than that in the control groups. The community profiles showed the potential cooperative interactions between strain L303 and indigenous bacteria, thereby enhancing the TCS degradation in the real polluted water. The finding of this study could facilitate in developing appropriate bioaugmentation...
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