A selection strategy for enhancing exoelectrogenic consortium towards improved power generation in microbial fuel cells

Abstract

A selection method to develop an electrogenic consortium for improved power generation in microbial fuel cells (MFCs) is described. Raw domestic sewage was inoculated in a nutrient medium with Fe(III) hydroxide as the electron acceptor and subculturing was done. Subcultures were tested for Fe(III) reduction using ferrozine assay, microbial electron transfer activity using the Dye Reduction-based Electron-transfer Activity Monitoring (DREAM) assay and power generation in a MFC. Subcultures grown with Fe(III) demonstrated improvements in electron transfer activity and power generating ability, while cultures grown without Fe(III) did not exhibit these properties. The enriched Fe(III) subculture generated a maximum power density of 129.25 ± 7 mW/m 2 , while the subculture grown without Fe(III) generated only 81.54 ± 8 mW/m 2. A high correlation was observed between DREAM assay and power generation (r = +0.963). Cyclic voltammetry corroborated the high electrochemical activity of the Fe-enriched subculture. This method offers a simple and efficient way to enrich an electrogenic consortium for improved performance from routinely used inocula.

Functional Nanomaterial‐Modified Anodes in Microbial Fuel Cells: Advances and Perspectives

“…Subcultures grown with Fe(III) demonstrated improvements in EET efficiency and power generating ability, while cultures grown without Fe(III) did not exhibit the similar properties. [85] A new type of Fe/ Fe 2 O 3 NPs has been reported to be electrodeposited on the anode surface as the catalyst. [86] The thin layer of iron oxide formed on the anode surface enhances the surface wettability and the microorganism adhesion of the electrode, while decreases the electron transfer resistance.…”

“…The exoelectrogens were inoculated in a nutrient medium with Fe(III) hydroxide as the electron acceptor and subculturing was done. Subcultures grown with Fe(III) demonstrated improvements in EET efficiency and power generating ability, while cultures grown without Fe(III) did not exhibit the similar properties [85] . A new type of Fe/Fe 2 O 3 NPs has been reported to be electrodeposited on the anode surface as the catalyst [86] .…”