Microbial regulation of organic solid waste composting: Lignocellulose degradation (fertilization), process gas emissions, and containment of typical pollutants

Microbial agents represent a valuable class of additives that can enhance the value and effectiveness of compost products. This paper provides a comprehensive review of the mechanisms and applications of microorganisms in regulating lignocellulose degradation, controlling gas emissions, and managing typical pollutants during the composting of organic solid wastes. Inoculation with microbial agents can significantly improve the degradation efficiency, quality, and environmental friendliness of compost. Actinomycetes, fungi, and bacteria accelerate lignocellulose degradation through the secretion of enzymes (such as cellulases and lignin peroxidases), promote humus formation, and reduce emissions of greenhouse gases (e.g., CH₄, N₂O) and malodorous gases (e.g., NH₃, H₂S) by modulating microbial communities. Additionally, microbial agents can decrease the bioavailability of heavy metals, degrade antibiotics and resistance genes, and partially break down microplastics. Complex microbial agents exhibit greater stability and environmental adaptability due to synergistic effects. Future research should focus on screening and optimizing efficient functional microorganisms, employing genetic engineering to enhance microbial stability, optimizing composting processes with intelligent monitoring technologies, and exploring the synergistic mechanisms between microorganisms and other additives.