Polysaccharides from the leaves of Polygonatum sibiricum Red. regulate the gut microbiota and affect the production of short-chain fatty acids in mice

Polysaccharides from the rhizome of Polygonatum sibiricum display a variety of biological activities, including the regulation of intestinal microbiota, but the polysaccharides from the leaves of P. sibiricum have not been studied extensively. Here, we extracted crude polysaccharides from the leaves of P. sibiricum and further separated and purified them to study the effects of P. sibiricum polysaccharides (PsPs) on intestinal microbes and short-chain fatty acids (SCFAs). The PsPs had a total sugar content of 97.48% and a monosaccharide composition comprising mannose, rhamnose, galacturonic acid, glucose, xylose, and arabinose, with molar ratios of 6.6:15.4:4.5:8.8:40.7:24, respectively. The effects of PsPs on intestinal microflora in mice were also studied, with 16S sequencing results showing an increase in the relative abundance of Firmicutes and a decrease in Bacteroidetes at the phylum level. The abundance of Lactobacillus increased, while those of Lachnospiraceae and Bacteroides reduced (at the genus level) by PsPs treatment. The composition of microbes changed. Levels of SCFAs in the PsPs group were significantly increased compared with control mice, including acetic acid, propionic acid, and butyric acid. These results suggest that PsPs can act as prebiotics, regulating the intestinal tract probiotics.