A recent study by the Innovation Team of Clean Conversion and High-value Utilization of Farming Waste at the Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, revealed the microbial functional modularization mechanism and environmental-economic sustainability of the process of straw conversion into medium-chain fatty acids (MCFAs) through molecular omics analysis and life cycle assessment (LCA). The related findings have been published in Water Research.

The natural hydrolysis-acidification (HA) process of straw often faces insufficient selectivity between lactic acid (LAc) and acetic acid (HAc) and great difficulty in enrichment of both. Restructuring the microbial community can help directionally regulate the production of LAc and HAc, enhancing the efficiency of MCFA synthesis. However, there is no systematic research on the mechanism how HA regulation influences the directional assembly of functional microbes.

This study established a fully modularized, resource-recycling reaction system for the sustainable supply of MCFAs. Focusing on the HA process of corn straw, it systematically revealed the synergistic microbial metabolic mechanisms of LAc and HAc production. The study indicated that short-term silage of straw, suitable HA substrate concentrations and initial pH control accelerated LAc-HAc production. It analyzed the metabolic pathway through artificial intelligence (AI), and clarified key enzymes and associated microbes. The potential for MCFA production was enhanced through directional regulation, and an accurate acid production prediction model was established. LCA demonstrated the environmental and economic advantages of this technical route, providing a theoretical basis for the selection of high-value straw utilization pathways.

This study was supported by the National Key R&D Program of China, the Innovation Program of the Chinese Academy of Agricultural Sciences, etc.

Linkage: https://doi.org/10.1016/j.watres.2025.124628