阴阳室微生物燃料电池对磺胺嘧啶的降解性能及其产物生物毒性

Removal of Sulfadiazine by Cathode-anode Microbial Fuel Cells and the Biotoxicity of the Intermediate

抗生素类污染物对水体环境的污染日益严重,磺胺嘧啶(sulfadiazine,SDZ)作为一种典型的磺胺类药物,其降解研究引起广大研究者的关注。本研究采用阴阳室微生物燃料电池(microbial fuel cells,MFC),选择孔隙率高、导电性能良好的石墨毡为电极材料,探究MFC对SDZ的降解性能,并通过功率密度考察了以石墨毡为电极材料MFC的产电性能。采用UPLC-MS/MS测定该体系中SDZ的中间代谢产物。以大肠杆菌为受试菌体,对SDZ代谢产物的生物毒性进行了检测。结果表明,微生物驯化五个月后,SDZ初始浓度为40 mg/L时去除率可达到98.23%;由中间产物推测出两条主要的SDZ降解路径,其中苯亚磺酸为主要代谢产物;功率密度曲线表明以石墨毡为电极材料的MFC具有良好的产电性能;毒性检测结果表明,SDZ在降解周期末,其产物对大肠杆菌的生长并无产生抑制作用。

Antibiotics pollution to water environment is becoming more and more serious.As a typical sulfonamide drug,sulfadiazine(SDZ)has been widely used and its degradation mechanism in the natural environment has attracted the attention of many scholars.Cathode-anode microbial fuel cells(MFC)with high porosity and good conductivity were used as electrode materials to explore the effect of MFC on the degradation of SDZ,and the electrical performance of MFC with graphite felt as electrode material was investigated in power density.The intermediate metabolites of SDZ in the system were determined by UPLC-MS/MS.The biotoxicity of the metabolites of SDZ was detected with E.coli as the test cell.Results show that the removal efficiency of SDZ(40 mg/L)could reach 98.23%after 5-month microorganic domestication.Two main pathways of SDZ degradation were inferred from the intermediates,among which benzenesulfonic acid was the main metabolite.The power density curve shows that MFC with graphite felt as electrode material had good electrical performance.The results of toxicity test demonstrate that the intermediates product of SDZ had no inhibitory effect on the growth of E.coli at the end of degradation cycle.