Understanding the key regulatory functions of red mud in cellulose breakdown and succession of β-glucosidase microbial community during composting.

The purpose of this research was to explore the effects of red mud on cellulose degradation and the succession of β-glucosidase microbial community in composting to better enhance the quality of compost. The activity of β-glucosidase in the treatment group with red mud (T) was 0.42-1.07 times higher than that in the control group without red mud (CK) from day 7 to 21 of composting. The final cellulose degradation ratios of the T (84.73%) were 10.02% higher than that of the CK (74.71%). In addition, Proteobacteria, Actinobacteria, Firmicutes, and Ascomycota were the most dominant β-glucosidase-producing microbes, and these microbes were also the phyla causing composting performances differences in the high temperature, cooling, and maturity periods of CK and T. These results indicated that adding red mud can improve β-glucosidase activity and boost the breakdown of cellulose in composting process.