<i>In vitro</i> digestion and fecal fermentation of <i>Siraitia grosvenorii</i> polysaccharide and its impact on human gut microbiota

Abstract

In this study, the structure of <i>Siraitia grosvenorii</i> polysaccharides (SGPs) changed significantly after digestion. After 48 h of <i>in vitro</i> fecal fermentation, <i>M</i>_w decreased and the content of <i>C</i>_R showed a trend of increasing and then decreasing. The monosaccharide composition (glucose) of SGPs showed a trend of decreasing and then stabilizing during fecal fermentation, indicating that SGPs were partially degraded during <i>in vitro</i> fermentation and significantly degraded and utilized by the human intestinal microbiota. In addition, SGPs fermentation for 48 h increased the production of SCFAs especially acetic acid, propionic acid, and butyric acid. Moreover, after <i>in vitro</i> digestion and enzymatic digestion, the <i>in vitro</i> hypoglycemic activity of SGPs remained relatively high afterward, albeit reduced. This study contributes to a better understanding of the potential digestion and enzymatic mechanisms of SGP, which is important for the future development of SGP as a functional food and drug.