Effect of the compound bacteria agent on microbial community of the aerobic compost of food waste.

Abstract

In our study, we used 16SrRNA and ITS to investigate the microbial community composition and the effect of compound bacteria agent on the microbial community composition in the aerobic composting process of food waste (FW). At the bacterial level, the main phylum of Group A (compost naturally) were Proteobacteria and Firmicutes, and the main species were Pseudomonas_sp._GR7, Bacillus licheniformis and Pediococcus acidilactici. The main phylum of Group B (compost with compound bacteria agent) were Proteobacteria, Firmicutes and Streptophyta, and the main species were Klebsiella pneumonia, Cronobacter sakazakii, Macrococcus caseolyticus, Enterococcus faecalis, Citrobacter freundii and Bacillus velezensis. It is worth noting that Macrococcus caseolyticus may be able to improve the effect of odor which is an important sensory index during aerobic composting. At the fungal level, the main phylum of both Group A and B were Ascomycota, and the main species of Group A were Paecilomyces variotii, Byssochlamys spectabilis and Aspergillus fumigatus. The main species of Group B were Ogataea polymorpha and Millerozyma farinosa. Finally, the degradation rate of Group B was 81% that was about 15% higher than that of Group A, indicating that the compound bacteria agent could effectively improve the degradation rate and the composting process, while the low abundance of the compound bacteria agent in the composting process might be due to the small initial addition or the inhibition of other bacteria or fungi in the composting process.