State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; Liaoning Key Lab of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian 116023, China.
School of Life Science, Liaoning Normal University, Dalian 116081, China.
Sci Total Environ. 2020 May 20;718:137412. doi: 10.1016/j.scitotenv.2020.137412. Epub 2020 Feb 19.
A novel integrated system with quorum quenching (QQ) bacterium Burkholderia sp. ssn-2 bioaugmented graphene oxide/polypyrrole (GO/PPy) conductive polymercomposite membrane (CPM) in MBR with electric field (EMBR) was established. The integrated system exhibited the highest degradation efficiency for phenol (100%) and COD (93.2%-99.9%) during the 120 days operation. Membrane fouling in the integrated system was notably mitigated by the coupling effect of CPM + voltage and QQ bacterium ssn-2. The hydrophilicity and antibacterial activity of CPM inhibited the hydrophobic protein foulants adsorption, bacteria colonization and attachment on the CPM surface. Extracellular polymeric substances (EPS) content was positively correlated with N-acyl-homoserine lactones (AHLs) concentration, and decreased with AHLs degradation by QQ bacterium ssn-2. The increased negative charge of EPS on the CPM surface augmented the electrostatic repulsion between the EPS and cathode CPM in the integrated system. Moreover, the coupling effect altered the microbial communities. A decreased AHLs concentration had a significantly negative correlation with QQ bacterium ssn-2 enrichment, which exhibited the dual effects of degrading phenol and AHLs, and enriching biopolymer-degrading genera Clostridium sensu strict and Acidovorax in the integrated system and on the CPM surface. This can lead to a decrease in the EPS content.
一种新型的集成系统，该系统采用具有群体感应淬灭（QQ）功能的伯克霍尔德氏菌（Burkholderia sp.）ssn-2 对氧化石墨烯/聚吡咯（GO/PPy）导电聚合物复合膜（CPM）进行生物增强，并在电场（EMBR）存在的情况下置于膜生物反应器（MBR）中。在 120 天的运行过程中，该集成系统对苯酚（100%）和 COD（93.2%-99.9%）的降解效率最高。CPM+电压和 QQ 细菌 ssn-2 的耦合作用显著减轻了集成系统中的膜污染。CPM 的亲水性和抗菌活性抑制了疏水性蛋白质污染物的吸附、细菌的定殖和在 CPM 表面的附着。细胞外聚合物（EPS）的含量与 N-酰基高丝氨酸内酯（AHLs）浓度呈正相关，而通过 QQ 细菌 ssn-2 降解 AHLs 则会降低 EPS 的含量。CPM 表面 EPS 的负电荷增加增强了 EPS 与阴极 CPM 之间在集成系统中的静电排斥。此外，该耦合作用改变了微生物群落。AHLs 浓度的降低与 QQ 细菌 ssn-2 的富集呈显著负相关，这表明 QQ 细菌 ssn-2 具有降解苯酚和 AHLs 的双重作用，并在集成系统和 CPM 表面富集了生物聚合物降解属梭菌属（Clostridium sensu strict）和食酸菌属（Acidovorax），从而降低了 EPS 的含量。
