Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan.
Department of Civil and Environmental Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan.
Sci Rep. 2018 Jul 30;8(1):11427. doi: 10.1038/s41598-018-29821-9.
Membrane fouling in membrane bioreactors (MBR) remains a major issue and knowledge of microbes associated with biofilm formation might facilitate the control of this phenomenon, Thus, an anoxic/oxic membrane bioreactor (A/O-MBR) was operated under an extremely low organic loading rate (0.002 kg-COD·m·day) to induce membrane fouling and the major biofilm-forming bacteria were identified. After operation under extremely low organic loading condition, the reactor showed accumulation of total nitrogen and phosphorus along with biofilm development on the membrane surface. Thus, membrane fouling induced by microbial cell lysis was considered to have occurred. Although no major changes were observed in the microbial community structure of the activated sludge in the MBR before and after membrane fouling, uncultured bacteria were specifically increased in the biofilm. Therefore, bacteria belonging to candidate phyla including TM6, OD1 and Gammaproteobacteria could be important biofilm-forming bacteria.
膜生物反应器（MBR）中的膜污染仍然是一个主要问题，而对与生物膜形成相关的微生物的了解可能有助于控制这种现象。因此，在极低的有机负荷率（0.002kg-COD·m·day）下运行缺氧/好氧膜生物反应器（A/O-MBR）以诱导膜污染，并确定了主要的生物膜形成细菌。在极低有机负荷条件下运行后，反应器表现出总氮和磷的积累以及膜表面生物膜的发展。因此，认为发生了由微生物细胞裂解引起的膜污染。尽管在膜污染前后，MBR 中活性污泥的微生物群落结构没有观察到重大变化，但在生物膜中特别增加了未培养的细菌。因此，属于候选门的细菌，包括 TM6、OD1 和γ-变形菌门，可能是重要的生物膜形成细菌。
