固定化对功能菌群DDMZ1脱色效果及群落结构的影响

Effects of immobilization on decolorization performance and community structure of functional flora DDMZ1

采用从水解酸化反应器污泥样品中驯化筛选得到的天然功能菌群DDMZ1,使用聚乙烯醇(PVA)-海藻酸钠(SA)-沸石为固定化复合载体,以包埋交联法形成固定化DDMZ1小球。通过实验对比,分析游离化DDMZ1菌液和固定化DDMZ1小球对RB5偶氮染料的脱色效率;并分别对游离化DDMZ1菌液、循环使用20批次和30批次的固定化DDMZ1小球进行群落结构分析,探究其群落结构组成的差异性。结果表明:固定化DDMZ1小球对RB5偶氮染料的脱色效率和速率均优于游离化DDMZ1菌液,且二者微生物群落结构组成差异明显。固定化技术有利于群落结构的稳定,循环使用20次和30次的固定化DDMZ1小球群落结构组成相似度高,从属的分类水平分析上发现2种固定化DDMZ1小球中富集有大肠杆菌-志贺菌(Escherichia-Shigella)和兼性厌氧-拟杆菌属(Dysgonomonas),推测这2种菌属是固定化DDMZ1小球对RB5偶氮染料稳定高脱色效率的主要原因。

The natural functional bacteria DDMZ1,which was domesticated and screened from the sludge samples of hydrolysis acidification reactor,was used as the immobilized composite carrier,and the immobilized DDMZ1 spheres were formed by embedding and crosslinking method.Through experiments,the decolorization efficiency of free DDMZ1 bacterial solution and immobilized DDMZ1 pellets on RB5 azo dyes was compared and analyzed.The community structure of free DDMZ1 bacterial solution and immobilized DDMZ1 pellets recycled for 20 and 30 batches were analyzed respectively to explore the differences of their community structure composition.The results show that the decolorization efficiency and rate of immobilized DDMZ1 pellets for RB5 azo dyes were better than that of free DDMZ1 bacterial solution,and there were significant differences in microbial community structure between them.The immobilization technology is conducive to the stability of community structure.The community structure composition of immobilized DDMZ1 pellets recycled for 20 and 30 times is highly similar.Escherichia-Shigella and Dysgonomonas are enriched in the two immobilized DDMZ1 pellets at the subordinate classification level.It is speculated that these two genera are the main reasons for the stability and high decolorization efficiency of immobilized DDMZ1 beads for RB5 azo dyes.