title: Interactions between the antimicrobial agent triclosan and the bloom-forming cyanobacteria Microcystis aeruginosa.
abstract: Cyanobacteria can co-exist in eutrophic waters with chemicals or other substances derived from personal care products discharged in wastewater. In this work, we investigate the interactions between the antimicrobial agent triclosan (TCS) and the bloom-forming cyanobacteria Microcystis aeruginosa. M. aeruginosa was very sensitive to TCS with the 96h lowest observed effect concentration of 1.0 and 10μg/L for inhibition of growth and photosynthetic activity, respectively. Exposure to TCS at environmentally relevant levels (0.1-2.0μg/L) also affected the activities of superoxide dismutase (SOD) and the generation of reduced glutathione (GSH), while microcystin production was not affected. Transmission electron microscope (TEM) examination showed the destruction of M. aeruginosa cell ultrastructure during TCS exposure. TCS however, can be biotransformed by M. aeruginosa with methylation as a major biotransformation pathway. Furthermore, the presence of M. aeruginosa in solution promoted the photodegradation of TCS. Overall, our results demonstrate that M. aeruginosa plays an important role in the dissipation of TCS in aquatic environments but high residual TCS can exert toxic effects on M. aeruginosa.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Wuhan Zhongke Hydrobiological Environment Engineering Co., Ltd, Wuhan 430071, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yenan
authors.initials: Y
authors.lastname: Tu
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Chaofeng
authors.initials: C
authors.lastname: Song
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Tiancui
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, Nanjing 210008, China.
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
authors.forename: Jiantong
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China. Electronic address: chenxi.wu@ihb.ac.cn.
authors.forename: Chenxi
authors.initials: C
authors.lastname: Wu
mesh_terms: D004789:Enzyme Activation / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D052998:Microcystins / Q000378:metabolism; D046931:Microcystis / Q000187:drug effects*; D013482:Superoxide Dismutase / Q000378:metabolism; D014260:Triclosan / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D052998:Microcystins; D014874:Water Pollutants, Chemical; D014260:Triclosan; C078588:microcystin; D013482:Superoxide Dismutase; D005978:Glutathione
keywords: Biotransformation; Eutrophication; Photodegradation; Toxicity; Triclosan