Digestion of pectic polysaccharide from Brassica rapa L. in vitro and its effect on the intestinal microbiota in cyclophosphamide-treated mice

In this study, the digestion of pectic polysaccharide from Brassica rapa L. (BRP) in vitro and its effect on the intestinal microbiota in cyclophosphamide (Cy)-treated mice were investigated. As a result, the molecular weight ( M w ) of BRP was significantly decreased after simulated gastrointestinal digestion, and content of reducing sugars ( C R ) was significantly increased ( P < 0.05), implying that BRP was gradually degraded under gastrointestinal digestion conditions in vitro . In vivo , both 50 or 200 mg kg −1 ·BW/d of BRP significantly improved SCFAs concentrations that decreased by Cy treatment ( P < 0.05). Meanwhile, BRP enriched the alpha-diversity of intestinal microbiota and altered the microbial composition with an increase of Lactobacillus and a decrease of Clostridium, Ruminococcus, Oscillospira ( P < 0.05). Besides, BRP intervention was conducive to the recovery of mouse body weight, thymus and spleen indices, and contributed to improve the intestinal barrier.