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Arthrobactersp. strain CN2, capable of degrading 4-nitrophenol, was isolated from activated sludge. Degradation of 4-nitrophenol was optimized at pH 7.7, 30 °C, and 0.53% of glucose. Salt tolerance of 4-nitrophenol degradation was as high as 6% (w/v). Several biodegradation intermediates were identified and quantified by high-performance liquid chromatography and mass spectrometry. 4-Nitrocatechol is involved in the degradation of 4-nitrophenol by CN2. Scale-up of 4-nitrophenol degradation was conducted in a bioreactor with different salinity. When the salinity was below 7%, the degradation rate of 4-nitrophenol was above 90% (100 mg L−1, 3 L). [ABSTRACT FROM AUTHOR]

Abstract: The fungal strain LZM1 was isolated from activated sludge and found to be capable of utilizing nicosulfuron as the sole nitrogen source for growth. Based on morphological and internal transcribed spacer evaluations, LZM1 was identified as a Talaromyces flavus strain. Under optimum conditions (pH 6.1, 29°C), T. flavus LZM1 degraded 100% of the initially added nicosulfuron (100mgL–1) within 5d. T. flavus LZM1 was also found to be highly efficient in degrading tribenuron methyl, chlorsulfuron, bensulfuron methyl, ethametsulfuron methyl, cinosulfuron, and rimsulfuron. Metabolites from nicosulfuron degradation were identified by liquid chromatography mass spectrometry, and a possible degradation pathway was deduced. These results show that T. flavus LZM1 may possess potential to be used in bioremediation of nicosulfuron-contaminated environments. [Copyright &y& Elsevier]

Achromobacter xylosoxidans CS5, capable of utilizing endosulfan as the sole carbon, sulfur and energy source, was isolated from the activated sludge. Degradation of endosulfan by strain CS5 was examined by HPLC. Analysis of culture pH, cells growth, and residual endosulfan demonstrated that CS5 could degrade more than 24.8mg/l α-endosulfan and 10.5mg/l β-endosulfan after 8 days in aqueous medium, with the formation of endosulfan diol and endosulfan ether as the major metabolites. Cell-free extract of strain CS5 was able to metabolize endosulfan rapidly, and the degradative enzymes were constitutively expressed. Inoculation of strain CS5 was found to promote the removal of endosulfan in soil. Our results suggested that A. xylosoxidans CS5 might degrade endosulfan by a non-oxidative pathway. In addition, detoxification of endosulfan was evaluated using a Salmonella typhimurium TA1535/pSK1002 (umu-test). These finding suggested that the metabolism of endosulfan by strain CS5 was accompanied by significant reduction in the toxicity. [Copyright &y& Elsevier]