紫外/氯消毒技术对金黄色葡萄球菌的灭活作用  

UV/Chlorine Disinfection for Inactivation of Staphylococcus aureus

作　　者：王莉萍 叶成松 于鑫 方晶云 WANG Li-ping;YE Cheng-song;YU Xin;FANG Jing-yun(School of Environmental Science and Engineering,Sun Yat-Sen University,Guangzhou 510275,China;College of the Environment&Ecology,Xiamen University,Xiamen 361102,China)

机构地区：[1]中山大学环境科学与工程学院,广东广州510275 [2]厦门大学环境与生态学院,福建厦门361102

出　　处：《中国给水排水》2023年第13期71-75,共5页China Water & Wastewater

基　　金：国家自然科学基金资助项目(21922612、22176228)。

摘　　要：从可培养细菌数、细胞膜完整性和消毒过程中细胞内外DNA数量变化等方面综合探究了紫外/氯消毒技术对金黄色葡萄球菌的灭活效果及机制。结果表明,当氯投加量为1 mg/L、紫外剂量为120 mJ/cm^(2)时,紫外/氯消毒技术可灭活所有可培养的金黄色葡萄球菌(7.28-lg CFU/mL),而单独氯化和单独紫外分别灭活了5.10-lg和6.38-lg CFU/mL的金黄色葡萄球菌。自由基淬灭实验表明,紫外/氯消毒技术对金黄色葡萄球菌的灭活增强效果主要是紫外和氯的作用,自由基作用可忽略。流式细胞仪(FCM)和扫描电子显微镜(SEM)检测结果均证实氯化和紫外/氯消毒技术通过破坏细胞壁和细胞膜使得细菌失活。此外,紫外/氯消毒技术可有效去除细胞内DNA(iDNA)和游离质粒,并且自由基对质粒DNA表现出明显的去除效果,同时未引起溶液中细胞外DNA(eDNA)的数量增大。综上,紫外/氯消毒技术可以促进金黄色葡萄球菌的灭活,并同时控制细胞内外基因,这为紫外/氯消毒技术控制水体中的革兰氏阳性菌提供了参考。This paper investigated the performance and mechanism of UV/chlorine process for inactivation of Staphylococcus aureus from the aspects of culturable bacteria number,cell membrane integrity and changes in intracellular and extracellular DNA(iDNA/eDNA)numbers during disinfection.When the dosages of chlorine and UV were 1 mg/L and 120 mJ/cm^(2),the UV/chlorine process could inactivate all culturable Staphylococcus aureus(7.28⁃lg CFU/mL),while chlorination alone and UV alone inactivated 5.10⁃lg CFU/mL and 6.38⁃lg CFU/mL of Staphylococcus aureus,respectively.The free radical scavenging test showed that the enhanced inactivation of Staphylococcus aureus by the UV/chlorine process was mainly due to the roles of UV and chlorine,and the effects of free radicals could be ignored.The results of flow cytometry(FCM)and scanning electron microscopy(SEM)confirmed that chlorination and UV/chlorine caused bacterial inactivation through the destruction of cell wall and membrane.In addition,UV/chlorine process could effectively remove iDNA and free plasmid,and free radicals showed an obvious plasmid DNA removal ability,while the concentration of eDNA in solution did not increase.In conclusion,the UV/chlorine process promoted the inactivation of Staphylococcus aureus and controlled both intracellular and extracellular genes,which provided a theoretical basis for UV/chlorine disinfection process to control the growth of gram⁃positive bacteria in water.

关 键 词：紫外/氯消毒 自由基 金黄色葡萄球菌 胞内DNA 胞外DNA 

分 类 号：TU991[建筑科学—市政工程]