Characterization of triclosan metabolism in Sphingomonas sp. strain YL-JM2C

• Published in: Scientific reports 2016-02, Vol.6 (1), p.21965-21965, Article 21965
• Main Authors: Mulla, Sikandar I., Wang, Han, Sun, Qian, Hu, Anyi, Yu, Chang-Ping
• Format: Article
• Language: English
• Subjects: 2,4-Dichlorophenol; 631/326/171/1878; 704/172/169/896; Activated sludge; Aquatic ecosystems; Bacteria; Biodegradation; Biomass; By products; Carbon; Carbon dioxide; Carbon Isotopes - chemistry; Cell surface; Chlorophenols - analysis; Contaminants; Fatty acids; Fatty Acids - biosynthesis; Gas chromatography; Gas Chromatography-Mass Spectrometry; Humanities and Social Sciences; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; Hydrophobicity; Hydroquinone; Hydroquinones - analysis; Isotope Labeling; Mass spectrometry; Mass spectroscopy; Metabolism; Morphology; multidisciplinary; Oxidoreductases - metabolism; pH effects; Phenols; Phylogenetics; Phylogeny; Science; Sphingomonas - classification; Sphingomonas - growth & development; Sphingomonas - metabolism; Stable isotopes; Temperature; Temperature effects; Triclosan; Triclosan - analysis; Triclosan - metabolism; Wastewater treatment; Wastewater treatment plants; Water treatment
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep21965

Triclosan (TCS) is one of the most widespread emerging contaminants and has adverse impact on aquatic ecosystem, yet little is known about its complete biodegradation mechanism in bacteria. Sphingomonas sp, strain YL-JM2C, isolated from activated sludge of a wastewater treatment plant, was very effective on degrading TCS. Response surface methodology (RSM) was applied to optimize the conditions like temperature and pH. From RSM, the optimal TCS degradation conditions were found to be 30 °C and pH 7.0. Under optimal conditions, strain YL-JM2C completely mineralized TCS (5 mg L −1 ) within 72 h. Gas chromatography-mass spectrometry analysis revealed that 2,4-dichlorophenol, 2-chlorohydroquinone and hydroquinone are three main by-products of TCS. Furthermore, stable isotope experimental results revealed that the 13 C 12 -TCS was completely mineralized into CO 2 and part of heavier carbon ( 13 C) of labeled TCS was utilized by strain YL-JM2C to synthesize fatty acids (PLFAs). Cell surface hydrophobicity (CSH) and degradation test results suggested that the strain could enhance degradation capacity of TCS through increasing CSH. In addition, the bacterium also completely degraded spiked TCS (5 mg L −1 ) in wastewater collected from the wastewater treatment plant. Hence, these results suggest that the strain has potential to remediate TCS in the environment.