Bacterial community composition and structure of biofilms developing on nanofiltration membranes applied to wastewater treatment
Bacterial community composition and structure of biofilms developing on nanofiltration membranes applied to wastewater treatment
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DOI：
10.1016/j.watres.2007.05.021
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发表时间：
2007-09-01
期刊：
影响因子：
12.8
通讯作者：
Dosoretz, Carlos G.
中科院分区：
文献类型：
--
作者：
Ivnitsky, Hanan;Katz, Ilan;Dosoretz, Carlos G.
研究了不同温度（20、25或34摄氏度）和操作时间（8小时至24天）下错流纳滤膜上形成的生物膜的结构和微生物群落。给水包括三级质量废水流出物或模拟中等质量流出物的合成介质。每次运行后，对膜进行尸检，以进行细菌计数、细菌群落组成和显微镜可视化（SEM、CLSM和AFM/NSOM）。通过聚合酶链反应-变性梯度凝胶电泳（PCR-DGGE）结合优势条带的16 S rRNA基因片段的序列分析来分析群落组成，在8 h内观察到多糖的沉积和初始细菌定殖，而从2-3 d开始明显影响膜通透性的生物膜明显发育。无论应用的条件如何，生物膜中的异养菌平板计数为3-4 × 10（6）CFU/cm（2），生物污垢层的厚度为20-30 μ m。从14个独立实验获得的总共22个序列中，鉴定的大多数种属为革兰氏阴性（22个序列中的19个）。变形菌被发现是一个普遍的组在所有情况下（16的22个序列），其中，SS-亚类是最主要的（8个序列），其次是γ-亚类（5个序列）。假单胞菌/伯克霍尔德菌属、罗尔斯通菌属、拟杆菌属和鞘氨醇单胞菌属为优势菌群。即使微生物种群可能是重要的生物污损模式，膜渗透性下降似乎更显着的影响外聚合物（EPS）的形成和积累。(c)2007爱思唯尔有限公司保留所有权利。
The structure and microbial communities of biofilms developing on cross-flow nanofiltration (NF) membranes at different temperatures (20, 25 or 34 degrees C) and operation lengths (8h-24days) were studied. Feedwater comprised tertiary quality wastewater effluent or synthetic media mimicking effluents of intermediate quality. After each run, the membranes were autopsied for bacterial enumeration, bacterial community composition and microscopy visualization (SEM, CLSM and AFM/NSOM). Community composition was analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) coupled with sequence analysis of 16S rRNA gene fragments from dominant bands.Deposition of polysaccharides and initial bacterial colonization were observed within 8 h, whereas developed biofilms markedly affecting membrane permeability were evident from days 2-3 onwards. Regardless of applied conditions, the heterotrophic plate counts in the biofilm were 3-4 x 10(6) CFU/cm(2) and the thickness of the biofouling layer was 20-30 mu m. From a total of 22 sequences obtained from 14 independent experiments, most species identified were Gram negative (19 of 22 sequences). Proteobacteria were found to be a prevalent group in all cases (16 of 22 sequences) and among it, the ss-subclass was the most predominant (8 sequences), followed by the gamma-subclass (5 sequences). Pseudomonas/Burkholderia, Ralstonia, Bacteroidetes and Sphingomonas were the dominant groups found in most cases. Even though the microbial population might be important with respect to biofouling patterns, membrane permeability decline seems to be more substantially influenced by the formation and accumulation of exopolymeric substances (EPS). (c) 2007 Elsevier Ltd. All rights reserved.