锌铜胁迫对Bacillus vallismortis EPS组分变化特征及其吸附性能的影响  

Influence of the stress of Zn(Ⅱ) and Cu(Ⅱ) on component changes and sorption behavior of extracellular polymeric substances( EPS ) from Bacillus vallismortis

作　　者：简静仪 宋卫锋[1] 李海宇[1] 杨梓亨 丁培菲 

机构地区：[1]广东工业大学环境科学与工程学院,广州510006

出　　处：《环境科学学报》2017年第6期2099-2106,共8页Acta Scientiae Circumstantiae

基　　金：广东省科技计划项目(No.2014A020209077)~~

摘　　要：近年来,微生物胞外聚合物(EPS)在吸附重金属方面的潜能引起了人们的广泛关注,但关于重金属对微生物及其EPS特性的影响鲜有报道.Bacillus vallismortis对锌铜矿捕收剂苯胺黑药具有良好的降解能力.为了解重金属对菌株的胁迫影响,探讨二者之间的相互作用,研究了Zn(Ⅱ)、Cu(Ⅱ)胁迫对菌株EPS产量、组分变化特征及其吸附性能的影响.结果表明,在Zn(Ⅱ)胁迫下,菌株培养至稳定期产生的EPS最多,当Zn(Ⅱ)为12 mg·L^(-1)时EPS产量翻倍,达到100.84 mg·g^(-1)(以VSS计),Zn(Ⅱ)能刺激菌株产生更多富含—COOH和—OH的胞外多糖;菌株在Cu(Ⅱ)胁迫下需培养至对数期产生的EPS最多,在Cu(Ⅱ)为6 mg·L^(-1)情况下EPS产量最高为60.65 mg·g-1(以VSS计),Cu(Ⅱ)的胁迫作用提高了菌株EPS中富含N—H和C—N的蛋白质含量;吸附实验结果表明,2种金属能通过胁迫菌株产生特异性EPS,为金属离子提供大量适用性结合点位,显著提高对重金属的去除能力.研究结果对应用生物法处理同时含有重金属和有机物的复合型选矿废水具有一定的指导意义.The potential for heavy metal sorption of extracellular polymeric substances（EPS） has attracted wide attention recently,however,there were few reports about the influence of heavy metal on EPS. Bacillus vallismortis has been found to be efficient in degradation of aniline which is a kind of sand bergerite collecting agents. For better understanding of interaction between heavy matals and EPS,the influences of Zn（Ⅱ） and Cu（Ⅱ） stress on the production,component changes and sorption behavior of EPS were investigated. The results show that in the presence of Zn（Ⅱ）, the production of EPS harvested in stationary phase increased to 100.84 mg·g^-1 VSS under 12 mg·L^-1 Zn （Ⅱ） exposures. Zn（Ⅱ） promoted the strain to produce polysaccharides containing -COOH and -OH. The production of EPS harvested in exponential phase under stress of Cu （Ⅱ） was up to 60.65 mg·g^-1 VSS under 6 mg·L^-1 Cu（Ⅱ） exposures. Cu（Ⅱ） increased the extracellular proteins with rich N-H and C-N. The results of adsorption experiment indicated that both of two metal ions could prompt the production of EPS,which offered available binding sites and as a result they could improve the heavy metal binding capacities of EPS. These results might provide a practical guidance for the application of using biotechnique to treat wastewater containning organics and heavy metals.

关 键 词：胁迫 重金属 胞外聚合物 吸附 红外光谱 

分 类 号：X172[环境科学与工程—环境科学] X703.1