Abstract:Objective Microorganisms play a critical role in the treatment of food waste. Elucidating their community structure and functional characteristics is essential for optimizing treatment processes and improving operational efficiency. Methods We employed high-throughput 16S rRNA gene amplicon sequencing to investigate the microbial community structures and potential functions in three systems: the anaerobic digestion system, the wastewater treatment system, and the air purification system (including biofilters and deodorization towers), in a food waste treatment facility. Results The microbial communities differed significantly in diversity and composition across systems. The anaerobic digestion system exhibited lower microbial diversity and richness, primarily influenced by environmental factors such as temperature, pH, and biochemical oxygen demand (BOD). Functional analysis indicated that organic matter degradation was the dominant microbial function across the facility. Specifically, the anaerobic system was enriched with genera such as Defluviitoga, Methanothermobacter, and Lentimicrobium, which were involved in hydrolysis, fermentation, and methanogenesis. The wastewater treatment system was dominated by Candidatus Anammoximicrobium, Nitrolancea, and Truepera, which drove organic matter degradation and nitrogen transformation processes, including anaerobic ammonium oxidation (anammox), nitrification, and denitrification. The air purification system was enriched with Chryseobacterium and Paracoccus, which were associated with biofilm formation and the degradation of volatile organic compounds and sulfur-containing compounds. Conclusion The microbial community characteristics in each treatment system was closely associated with system-specific operational conditions. The enrichment of functionally distinct microbial taxa reflected their ecological roles. In the anaerobic digestion system, methanogens and syntrophic bacteria cooperatively facilitated organic matter degradation and methane production. In the wastewater treatment system, nitrogen-cycling bacteria ensured efficient nitrogen removal. In the air purification system, the enrichment of heterotrophic degraders and sulfur compound-metabolizing genera (e.g., Sphingobium and Flavobacterium) enhanced deodorization performance. These findings provide a theoretical basis for microbial community regulation and process optimization in food waste treatment facilities.
