Response to inhibitory conditions of acetate-degrading methanogenic microbial community

Publication date: Available online 5 November 2019Source: Journal of Bioscience and BioengineeringAuthor(s): Hui-Zhong Wang, Jie Li, Yue Yi, Masaru K. Nobu, Takashi Narihiro, Yue-Qin TangInvestigating the effects of different kinds of inhibitors on the activity and structure of acetate-degrading microbial community involved in methane fermentation is critically important for developing countermeasures to make the fermentation process stable under different inhibitory conditions. In the present study, a mesophilic chemostat fed with acetate as the sole carbon source was constructed. Microbial community analysis based on high-throughput sequencing of 16S rRNA revealed that Methanothrix was the dominant methanogen and a variety of bacteria including acetate-oxidizing bacteria such as Tepidanaerobacter, Mesotoga, Geovibrio, and Geobacter were found. The activity and dynamic changes of the acetate-degrading microbial community under different inhibitory conditions were investigated. Addition of 600 mg L−1 ammonium and 150 mg L−1 sulfide reduced nearly half of the biogas production. The response of microbial community to sulfide inhibition was quicker than ammonium but the structure could recover in a short time. Addition of 8 mg L−1 chlortetracycline (CTC) and 160 mg L−1 enrofloxacin (EFX) exhibited a similar inhibitory effect on biogas production, with approximately 35% reduction. Compared to ammonium and sulfide, antibiotics showed stronger selective inhibition o...
Source: Journal of Bioscience and Bioengineering - Category: Biomedical Science Source Type: research