还原Cr(Ⅵ)的混菌胞外聚合物和细菌群落结构分析  

Analysis of extracellular polymeric substances and bacterial community in mixed cultures for Cr(VI) reduction

作　　者：张恩华[1,2] 戴幼芬 肖勇[2] 陈必链[3] 杨朝晖[1] 赵峰[2] ZHANG En-hua;DAI You-fen;XIAO Yong;CHEN Bi-lian;YANG Zhao-hui;ZHAO Feng(Key Laboratory of Environmental Biology and Pollution Control, College of Environmental Science and Engineering, Hunan University,Changsha 410082, China;Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China;College of Life Sciences, Fujian Normal University, Fuzhou 350108,China)

机构地区：[1]湖南大学环境科学与工程学院,环境生物与控制教育部重点实验室,湖南长沙410082 [2]中国科学院城市环境研究所,中国科学院城市污染物转化重点实验室,福建厦门361021 [3]福建师范大学生命科学学院,福建福州350108

出　　处：《中国环境科学》2017年第1期352-357,共6页China Environmental Science

基　　金：国家自然科学基金资助项目(51208490,51478451);中国科学院知识创新工程青年人才领域前沿项目(IUEQN201306)

摘　　要：为了更好地理解混菌还原Cr(Ⅵ)机制,比较了源于活性污泥的混菌体系在厌氧和好氧培养条件下Cr(Ⅵ)还原能力的差异,分析了相应的胞外聚合物(EPS),并通过MiSeq高通量测序研究了细菌群落结构及多样性.结果表明,好氧和厌氧两个混菌体系对Cr(Ⅵ)均没有明显的吸附作用;随着培养时间的延长,溶液中的Cr(Ⅵ)逐渐被还原为Cr(Ⅲ);培养至72h,好氧体系和厌氧体系对Cr(Ⅵ)的还原率分别达到67%和78%.两种培养条件下,不加Cr(Ⅵ)对照组EPS含量明显高于加Cr(Ⅵ)实验组;实验组细菌群落多样性均低于相应对照组,厌氧体系细菌群落多样性低于好氧体系.接种源中的优势细菌类群为变形菌门、厚壁菌门、绿弯菌门和放线菌门,但经过36d驯化培养后所有样本都是变形菌门占主导地位;在属水平上,柠檬酸杆菌属在Cr(Ⅵ)胁迫下相对丰度明显下降,而肠杆菌属相对丰度明显提高.To better understand the mechanisms of Cr(VI)reduction by mixed microbial communities,Cr(VI)bio-reduction was performed by mixed cultures from activated sludge under both aerobic and anaerobic conditions.Thecomponent and quantity of extracellular polymeric substances(EPS)were analyzed,and the bacterial communities weredetermined by high throughput sequencing.No chromium adsorption was observed by the mixed cultures in the presentstudy.In the12th acclimation cycle,67%and78%of Cr(VI)was reduced by the aerobic and anaerobic cultures in72h,respectively.More EPS were extracted from control groups than that from Cr(VI)-treated groups.The diversities ofbacterial communities in Cr(VI)-treated groups were lower than those in control groups.Proteobacteria,Firmicutes,Chloroflexi and Actinobacteria were the most dominant phyla in the inoculum sample.But,all samples were dominatedby Proteobacteria after a culture of36days with Cr(VI).While the relative abundance of Citrobacter in cultures wassignificantly decreased by Cr(VI),the relative abundance of Enterobacter was remarkably increased by Cr(VI).

关 键 词：重金属 CR(VI)还原 胞外聚合物 细菌群落 高通量测序 

分 类 号：X172[环境科学与工程—环境科学]