Chinese yam (Dioscorea opposita) and its bioactive compounds: the beneficial effects on gut microbiota and gut health

Chinese yam, a group of vegetables belonging to the species Dioscorea opposita, has a long history of use on promoting gut health. Recent studies highlighted the diverse components found in yam (Dioscorea spp.), including yam polysaccharides, dioscin, and β-carotene, which play a significant role in gut protection. These components were shown to alleviate inflammatory bowel disease, improve colitis, and positively modulate intestinal flora. Yam polysaccharides and β-carotene help restore the balance of intestinal flora by increasing the levels of beneficial lactic acid bacteria such as Bifidobacterium and Lactobacillus, as well as Parabacteroides spp., while inhibiting the growth of harmful bacteria such as Clostridium perfringens and species from Firmicutes phylum (Lachnoclostridium and Marvinbryantia spp.). Additionally, dioscin has been found to improve intestinal permeability. This review will power further research into the potential functions of these compounds and yam as whole food, as well as for yam-based food product development.