Bioaugmentation of microbial fuel cells with <i>Geobacter sulfurreducens</i> strain 60473 for boosting power outputs from food wastes

Microbial fuel cells are expected to be applied to sustainable power generation, while substantial increases in process performances, including power output, are necessary for practical application. Here we examined the utility of bioaugmentation with electro-active bacteria for boosting power outputs from microbial fuel cell reactors. Single-chamber reactors were operated using digester effluent as an inoculum and food wastes as organic substrates, and effects of bioaugmentation with Geobacter sulfurreducens strain 60473 were examined. It has been shown that bioaugmentation with strain 60473 substantially improves organics removal and power output, and the maximum power density (per anode projection area) reaches over 1700 mW m-2, a value tenfold larger than that without bioaugmentation. Metabarcoding analyses showed that Geobacter shared more than 40% of anode bacteria in 60473-augmented reactors. These results suggest the utility of bioaugmentation with strain 60473 for improving the performance of microbial fuel cells treating food wastes.