The response and anti-stress mechanisms of nitrifying sludge under long-term exposure to Cd Se quantum dots
作者机构:Shaanxi Key Laboratory of Environmental EngineeringXi’an University of Architecture and TechnologyXi’an 710055China Key Lab of Northwest Water ResourceEnvironment and EcologyMinistry of EducationXi’an University of Architecture and TechnologyXi’an 710055China
出 版 物:《Journal of Environmental Sciences》 (环境科学学报(英文版))
年 卷 期:2024年第135卷第1期
页 面:174-184页
核心收录:
学科分类:083002[工学-环境工程] 0830[工学-环境科学与工程(可授工学、理学、农学学位)] 08[工学]
基 金:supported by the Special Scientific Research Program of Shaanxi Provincial Education Department (No.21JK0716) the Natural Science Basic Research Project of Shaanxi Province (No.2022JM-217) the National Natural Science Foundation of China (No.51878537)
主 题:Quantum dots Activated sludge Extracellular polymeric substances Microbial community Antioxidant effect
摘 要:The wide application of CdSe quantum dots(QDs)increases its stress risk to sewage treatment *** study evaluated the response of nitrification performance,floc characteristics and microbial community of nitrifying sludge under long-term exposure to CdSe *** showed CdSe QDs(≥1 mg/L)would decrease the activity of ammonia monooxygenase(AMO).Under the stress of 30 mg/L CdSe QDs,the activity of AMO was reduced by 66%,while the activities of hydroxylamine oxidase and nitrite oxidoreductase were enhanced by 19.1%and 26%,***,the final nitrification effects were not adversely affected,and the production rates of NO_(2)^(-)-N and NO_(3)^(-)-N were ***,CdSe QDs improved biomass concentration in sludge and maintained the stability of sludge *** throughput sequencing analysis showed that CdSe QDs evidently reduced the abundance and diversity of microbial community in nitrifying *** abundances of amino acid metabolism and lipid metabolism were ***,CdSe QDs decreased the fluorescence intensity of tryptophan-like protein from 2,326 to 1,179 *** loosely bound extracellular polymeric substances(EPSs)and from 3,792 to 3,117 *** tightly bound *** relieve CdSe QD stress,the polysaccharide content increased from0.31 to 0.61 mg/g MLSS and intracellular antioxidant defense was *** CdSe QD level increasing to 30 mg/L,the total antioxygenic capacity and the activities of catalase were enhanced up to 411%and 143.2%,***,CdSe QDs had little adverse effects on cell membrane integrity,microbial metabolism and the abundance of Nitrospirae.