JIA Wenxia, LI Menglin, DING Yijie, QU Xinyan, LIU Qian, LI Qingjun, LIU Hongyan
The aim was to prepare yam-resistant starch by a dual enzyme method and to discuss its protective effect on ulcerative colitis.Using yield as an index, an orthogonal experimental design was employed to optimize the yam-resistant starch preparation procedure.A control group, model group, positive drug group, and yam-resistant starch low, medium, and high dosage groups were randomly assigned to sixty C57BL/6 mice.To induce ulcerative colitis in mice, 25 g/L dextran sulfate sodium (DSS) was administered.The mice were noted for their body weights and general health, the colon length was measured, and the disease activity index was computed.The histology of the mouse colon, inflammatory factors, intestinal tight junction protein, mucin expression, transcription factors ROR-γt and Foxp3 mRNA expression, and short-chain fatty acid (SCFA) content were also evaluated.Results indicated that a 20% starch emulsion concentration, 16 U/g pullulanase, 20 U/g heat-resistant α-amylase, and an 18-hour retrogradation interval were the ideal parameters for the manufacture of resistant starch.Of the three treatment groups, the high-dose yam-resistant starch group had the greatest effect.In mice with ulcerative colitis, it significantly decreased colonic histological damage, elevated IL-10 expression, and lowered IL-6, IL-17, and TNF-α expression in comparison to the model group.Furthermore, it enhanced the expression of MUC2 and ZO-1, stimulated the expression of Foxp3 mRNA, suppressed the expression of ROR-γt mRNA, and raised the amount of acetic, propionic, and butyric acids in feces.Therefore, yam resistant starch could improve the amount of short-chain fatty acids in the gut, reduce inflammation, protect the intestinal barrier, restore immunological balance in the gut, and reduce UC symptoms in mice.This could serve as a foundation and guide for the creation of functional foods that prevent and treat ulcerative colitis.
