title: Rapid degradation of sulphamethoxazole and the further transformation of 3-amino-5-methylisoxazole in a microbial fuel cell.
abstract: Sulphamethoxazole (SMX) is extensively used in humans and livestock, but its appearance in natural water raises environmental concerns. This study demonstrated that SMX and its degradation product, 3-amino-5-methylisoxazole (3A5MI), could be effectively degraded in microbial fuel cell (MFC) reactors. Approximately 85% of 20 ppm SMX was degraded within 12 h, and this was a more rapid biodegradation rate than has been previously shown in the literature. In addition, 3A5MI, a toxic chemical that forms in the SMX degradation process, can be further mineralized. The degradation products of SMX were detected by mass spectrometry, and three speculated by-products were confirmed with chemical standards. It was observed that nitrogen atoms of SMX were progressively eliminated during the degradation process, which may relate with the degradation of SMX and 3A5MI. An antibacterial activity test showed that the biotoxicity of SMX towards Shewanella oneidensis MR-1 and Escherichia coli DH5α was greatly reduced after MFC treatment. Moreover, the ATP level of the MFC microbe was nearly threefold higher than that in open-circuit controls, which may be related to the rapid degradation of SMX in MFCs. This study can facilitate further investigations about the biodegradation of SMX.
authors.affiliation: Key Laboratory of Urban Pollutant Conversion, Chinese Academy of Sciences, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Yulei
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: majun@hit.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: Key Laboratory of Urban Pollutant Conversion, Chinese Academy of Sciences, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address: fzhao@iue.ac.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D001673:Biodegradation, Environmental; D001674:Bioelectric Energy Sources / Q000382:microbiology; D004785:Environmental Pollutants / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects; D007555:Isoxazoles / Q000378:metabolism; D059013:Microbial Consortia / Q000502:physiology; D020592:Shewanella / Q000187:drug effects; D013420:Sulfamethoxazole / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology
chemical_list: C000611126:3-amino-5-methylisoxazole; D000900:Anti-Bacterial Agents; D004785:Environmental Pollutants; D007555:Isoxazoles; D000255:Adenosine Triphosphate; D013420:Sulfamethoxazole
keywords: 3-Amino-5-methylisoxazole; Antibiotics; Biodegradation; Degradation pathway; Sulphamethoxazole