Power generation and microbial community analysis in microbial fuel cells: A promising system to treat organic acid fermentation wastewater

To explore a sustainable and efficient treatment approach for organic acid fermentation wastewater, two microbial fuel cells (MFCs) systems inoculated with wastewater or domesticated microbial community were constructed in this study. Compared with the MFC inoculated with domesticated microbial community, the MFC inoculated with wastewater not only showed higher power density (543.75 mW m^-2) and coulomb efficiency (22.10%), but also exhibited higher removal rates of chemical oxygen demand (75.59%), total nitrogen (76.15%), and ammonia nitrogen (83.23%), meeting the demand of wastewater discharge standard of China. Sequencing analysis revealed that the MFC inoculated with wastewater were richer in microbial community, and some bacteria such as Saprospiraceae and Caldilineaceae were beneficial for its good performance. In contrast, the microbial community of the MFC inoculated with domesticated microbial community was relatively simple. These results indicated that MFCs may be a sustainable method for organic acid fermentation wastewater treatment without any preprocessing.