Dynamics of Bacterial Community during the Stable Operation of Anaerobic Baffled Reactor Monitored by Single-Strand Conformation Polymorphism

摘要

A laboratory-scale anaerobic baffled reactor (ABR) with seven chambers was employed as experimental equipment and the molasses wastewater was elected as experimental substrate. Chemical analyses were done to evaluate digester performance, as well as monitoring bacterial community by Single-Strand Conformation Polymorphism technique (SSCP) targeting the V1~V3 region of 16S rDNA genes. Results showed that the structure of bacterial community during the stable period did not vary as time , but altered obviously along the flow. The acidogenic phase (1 to 4 in 7 chambers) contained at least fourteen distinct bands, which were similar to Escherichia, Anaerophaga, Corynebacterium, Anaerolinea and Clostridium, etc. A rapid shift of the bacterium populations was observed when acidogenic phase transitioning to the methanogenic phase (5 to 7 of 7 chambers). Hydrogen-Producing Acetogen (HPA), which played minor part in Acidogenic phase, became the dominant species in methanogenic phase. And the genus Anaerolinea, together with genera Megaspharea, Acidaminococca, Anaerophage, Crynebacterium, and Corynebacterium, made up of the climax communities in methanogenic phase. All sequences of bands belonged to six phyla, Proteobacteria, 48.66%; Chloroflexi, 16.22%; Firmicutes, 13.60%; Bacteroidetes, 10.91%; Actinobacteria, 8.11%; Thermotogae, 2.70%. The bacterial community showed high diversity and outstanding alteration with the change of chambers of the baffled bioreactor.