Advances in Electricity-Steering Organic Waste Bio-Valorization for Medium Chain Carboxylic Acids Production

Medium chain carboxylic acids (MCCAs, e.g., caproic acid, caprylic etc.) with 6–12 carbon atoms are valuable platform chemicals produced from organic waste via microbial elongation metabolism named as reversed β-oxidation and fatty acid-biosynthesis cyclical pathway. Recently, many articles reported that electricity could not only serve the external electron donor provide reduction equivalent required for but also regulate microbiome structure metabolic behaviors to promote MCCAs formation. Electricity-steering bioproduction has become an appealing technique valorize low-value waste, paving alternative pathway net-zero emission energy systems sustainable socio-economic development. However, MCCAs’ steered by electric field been comprehensively reviewed. From a systematical analysis of publicly available literature, we first covered basic working principle, fermentation architecture, functional microflora, production driven electricity. The strategies substrate modulation, applied voltage/current regulation, electrode optimization, cooperation stimulation boosting electricity-driven then scrutinized extensively discussed. Ultimately, pressing knowledge gaps potential path forward proposed pointers consistently higher yield transition laboratory market.