The temporal profile of GH1 gene abundance and the shift in GH1 cellulase-producing microbial communities during vermicomposting of corn stover and cow dung.

Vermicomposting is a promising method for corn stover management to achieve bioresource recovery and environmental protection. Most ß-glucosidases, which limit the cellulose degradation rate during vermicomposting of corn stover, belong to glycoside hydrolase family 1 (GH1). This study was conducted with different earthworm densities to quantify the GH1 gene abundance and investigate the evolution of GH1 cellulase-producing microbial communities using qPCR and pyrosequencing. The results showed that ß-glucosidase activity, GH1 gene abundance, TOC, and microbial communities carrying the GH1 gene were affected by processing time and earthworm density. After introducing earthworms, ß-glucosidase activity increased to 1.90-2.13 U/g from 0.54 U/g. The GH1 gene abundance of treatments with earthworms (5.82E+09-6.70E+09 copies/g) was significantly higher than that of treatments without earthworms (2.48E+09 copies/g) on Day 45. Earthworms increased the richness of microbial communities. The relative abundances of Sphingobium and Dyadobacter, which are dominant genera harboring the GH1 gene, were increased by earthworms to peak values of 23.90% and 11.20%, respectively. Correlation analysis showed that Sphingobium, Dyadobacter, Trichoderma, and Starkeya were positively associated with ß-glucosidases. This work sheds new light on the mechanism of cellulose degradation during vermicomposting at the molecular level.

The Leap of Inulin Fructans from Food Industry to Medical Application.

As a dietary supplement, the efficacy of prebiotics has become a hot issue in recent years. Inulin is one of internationally recognized prebiotics and belongs to a group of non-digestible and fermentable carbohydrates. Currently, the food industry is increasingly using prebiotic inulin as a health-promoting substrate, not just as food supplement. In addition, inulin has also shown great promise in the treatment of various diseases. This article reviews the application of inulin in the food industry and summarizes physiological function of inulin. Through the review and prospect of the research on obesity, diabetes and mental illness, it provides the theoretical basis for the joint development of inulin in food industry and medical application.