Investigating the influence of Saccharomyces cerevisiae on microbial fuel cell performance through bioelectrochemical and biochemical approaches under varied operating conditions

This study examines the intricate relationships between Saccharomyces cerevisiae and microbial fuel cells (MFCs) operating under diverse oxygen conditions: aerobic, semi-anaerobic, and anaerobic. The research delves into the metabolic pathways of yeast, specifically analyzing variations in pH levels and alcohol synthesis. Electron transport chain routes on yeast cells are explored, correlating with electron transfer rates to electrodes. The anaerobic, semi-anaerobic, and aerobic conditions demonstrate respective electron transfer rate constant values of 0.186 ± 0.053, 0.763 ± 0.013, and 0.396 ± 0.006 s⁻¹, aligning with Laviron theory. Notably, MFCs under semi-anaerobic conditions achieve a substantial maximum power density of 17.077 ± 0.217 mW/m², surpassing both aerobic (10.622 ± 0.331 mW/m²) and anaerobic (6.371 ± 0.128 mW/m²) conditions. Biofilm formation on electrodes varies with conditions, with masses of 0.829 g (anaerobic), 0.276 g (semi-anaerobic), and 0.409 g (aerobic). The findings underscore the superior performance of semi-anaerobic conditions, resulting in the highest maximum power density for yeast MFCs, suggesting its potential for efficient bioenergy production.