A Review of Microbial Interactions and Enhancement Strategies for Medium-Chain Fatty Acids Production from Organic Wastes

Abstract

Medium-chain fatty acids (MCFAs) production from organic waste via microbial chain elongation (CE) technology represents a pivotal way toward high-value resource recovery. However, real organic wastes generally have complex composition, which results in intricate interspecies interactions in microbial consortium and affects MCFAs yield and process stability. Enhancing microbial cooperation and limiting competition constitute promising strategies for directing carbon flux and reducing equivalents toward the chain elongation pathway. This review provides insights into microbial interactions within real waste-fed chain elongation systems and summarizes key impact factors and recent research advances concerning the regulatory strategies for microbial cooperation. Interspecies interactions can be affected by organic waste compositions, microbial electron transfer pathways, environmental conditions, and quorum-sensing communication systems. Major optimization strategies were systematically introduced including the exogenous additions of signal molecules, supplementation of electron-transfer-mediated materials, and an advanced approach of synthetic microbial consortia. The current review aims to provide theoretical and technical support for enhancing the efficiency of MCFAs’ production from real organic wastes.