摘要
以Aeromonas veronii N8为研究对象,对其松散型胞外聚合物(LB-EPS)和紧密型胞外聚合物(TB-EPS)的性质及其吸Zn^(2+)特征进行了研究.结果表明,LB-EPS和TB-EPS具有不同的多糖及蛋白组成比例;与TB-EPS相比,LB-EPS的分子量分布范围较窄,但其平均分子量较大,TBEPS中含有一些LB-EPS不具有的富含芳香族氨基酸的蛋白质,而LB-EPS则含有少量TB-EPS不具有的腐殖酸类物质;1H NMR与XPS分析发现,两种EPS具有相似的结构与元素组成,但各元素在两者中的组成比例并不相同;LB-EPS和TB-EPS具有相似的Zn^(2+)吸附规律,经90 min后二者均能达到吸附平衡,但LB-EPS的吸附率一直大于TB-EPS,二者的吸附率则随着EPS浓度的增加而变大,并随着Zn^(2+)浓度的增加而变小;对比Zn^(2+)吸附前后,两种EPS中属于核酸、多糖与蛋白质在内的一些特征官能团的强度或位置则发生了一定的变化,表明这些特征峰在吸附过程具有不同的功能作用;而LB-EPS和TB-EPS的Zn^(2+)吸附过程则可分别采用Freundlich和Temkin模型进行描述.
In this work,the properties and Zn^（2＋）adsorption characterizations of the loosely bound extracellular polymer substances（ LB-EPS） and the tight-binding extracellular polymeric substances（ TB-EPS） from Aeromonas veronii N8 were studied. The results show that both EPS displayed the different composition proportion of protein and polysaccharide. Compared with TB-EPS,LB-EPS had the narrower molecule weight distribution and higher molecule weight. The ingredients of aromatic protein and humic acid were found in TB-EPS and LB-EPS,respectively. The spectrums of1 H NMR and XPS suggest that although TB-EPS and LB-EPS had the similar chemical structure and element composition,the composition ratio of various elements in both EPS was different. TB-EPS and LB-EPS also exhibited a similar Zn^（2＋）adsorption performance,and the adsorption equlibrium of both EPS could be achieved in 90 minutes. Additionally,the adsorption rates of both EPS were increased with the EPS concentration and decreased with the Zn^（2＋）concentration. After adsorption,the FTIR spectrums of both EPS show that some changes had taken place in the strength or position of some characteristic peaks originated from DNA,protein and polysaccharide,which implied that those functional groups acted the different function roles for the Zn^（2＋）adsorption. Furthermore,the Zn2 ＋adsorption of LB-EPS and TB-EPS might be described by Freundlich and Temkin models,respectively.
出处
《环境科学学报》
CAS
CSCD
北大核心
2016年第10期3665-3674,共10页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.31470577)
福建省自然科学基金(No.2015J01089)
福建省高等学校新世纪优秀人才支持计划(No.JA11070)
福建省高校杰出青年科研人才培育计划(No.JA10088)~~
作者简介
柴德芳（1989-），女，E-mail：18046030680@163．com
封磊（1977-），男，博士，副教授，主要从事环境生物技术研究．E—mail：fengleisp@126．com．
