环境工程学报2023，Vol.17Issue(12)：4037-4047,11.DOI:10.12030/j.cjee.202306077
紫外/过氧乙酸灭活大肠杆菌的效能及机理
Inactivation of Escherichia coli by peracetic acid combined with ultraviolet:Efficiency and mechanism
陈纪朝 1陈镇斌 1曹礼三 1成宇杰 1岳思阳 2王宗平 1谢鹏超1
作者信息
- 1. 华中科技大学环境科学与工程学院,武汉 430074
- 2. 华中科技大学建筑与城市规划学院,武汉 430074
- 折叠
摘要
Abstract
Pathogens pose great risks to public health and ecosystems.In this study,we investigated the efficiency and mechanism of the UV/peracetic acid(UV/PAA)process in inactivating Escherichia coli(E.coli)which served as the reference microorganism.The effects of PAA,UV dosages and water matrices on the inactivation rates of E.coli were systematically assessed,the generated reactive species were detected and the changes in cell morphology during inactivation were observed.Results showed that with a PAA concentration of 60 μmol·L-1 and UV intensity of 2.25x10-7 Einstein·(s·L)-1,the inactivation rate of E.coli reached 4.71 log after a 3 min reaction.An increase of 2.76 log and 0.82 log could be realized compared with that in the PAA alone and UV alone processes,respectively.Then,elevating the PAA concentrations and UV irradiation dosages would promote the inactivation efficiency.The inactivation rates of E.coli under UV/PAA were slightly inhibited by NH4+and Cl-,while humic acid(HA)exhibited a strong inhibitory effect.Moreover,the quenching experiments and electron paramagnetic resonance detection suggested that both hydroxyl(HO·)and organic radicals(RO·)contributed to the inactivation of E.coli.The observation using a confocal laser scanning microscope and a scanning electron microscope revealed that the inactivation of E.coli under UV/PAA caused slight damage to the cell membrane but did not result in complete cell integrity loss.Although the results from the fluorescence excitation-emission matrices analysis suggested the release of bacterial organic matter increased with cell membrane damage in the UV/PAA process,the released protein-like components with high molecular weight could be subsequently oxidized into humic acids-like components with low molecular weight.关键词
紫外线/过氧乙酸/大肠杆菌/消毒/自由基Key words
ultraviolet/peracetic acid/Escherichia coli/disinfection/radicals分类
资源环境引用本文复制引用
陈纪朝,陈镇斌,曹礼三,成宇杰,岳思阳,王宗平,谢鹏超..紫外/过氧乙酸灭活大肠杆菌的效能及机理[J].环境工程学报,2023,17(12):4037-4047,11.
