Mechanism That Allows Manno-Oligosaccharide To Promote Cellulose Degradation By Microbes And Composting of Cow Manure With Straw

Abstract

New sugar source, manno-oligosaccharide, can regulate the structure of microbes. The effects of adding manno-oligosaccharide at four different levels (0, 0.1%, 0.5%, and 1% w/w compost) to cow manure–straw compost on the composting process, degradation of lignocellulose, and bacterial community in this study was investigated. The results showed that adding 0.5% manno-oligosaccharide had the greatest effects on accelerating the composting process, reducing the toxicity, and improving the stability of the product. After composting for 25 days, 0.5% oligosaccharide treatment can decrease the hemicellulose, cellulose, and lignin contents to 2.25%, 11.25%, and 7.07% respectively, compared with CK. Manno-oligosaccharide affected the distribution of the bacterial community, inhibited pathogenic bacteria, and improved the abundance of functional genes. Finally, adding 0.5% manno-oligosaccharide mainly affected the degradation of lignocellulose by enhancing the C/N value and the abundances of Streptomyces and the secretion system during composting was demonstrated by redundancy analysis.