Chinese yam (Dioscorea Opposita Thunb.) is an important functional food as well as a source for natural medicine due to its several pharmacological activities. Polysaccharide is one of the important bioactive substances of Chinese yam. The biological activity of natural polysaccharide is closely related to how it is digested, absorbed and utilized in the host. We invested the gastrointestinal digestion and fecal fermentation behavior of polysaccharide from Chinese yam (CYP). The molecule weight of CYP remained unchanged in vitro gastral and intestinal digestion. Following 24 h of fecal fermentation, 49.0% of the total carbohydrate in the CYP was consumed. The total short chain fatty acids (SCFAs) productions, acetic, propionate, butyrate acid, and lactate acid significantly increased compared to the blank group. Simultaneously, CYP modulated the composition and abundance of beneficial microbiota, especially Lactobacillus spp. and Bifidobacterium spp. Compared with non-fermented CYP, CYP fermentation stimulated TNF-α and IL-10 secretion of macrophage RAW 264.7. The results suggest that CYP could potentially be a functional food to improve gut health.

Molecular weight distribution of CYP after artificial simulated gastric (A), small intestinal digestion (B) and fermentation by human fecal microbiota (C) was measured by APC. Effect of CYP on the percent of community abundance on species level (D).

Mingwei Zhang

Appearances