In-situ complexation of rice starch and nobiletin by extrusion alleviates ulcerative colitis and modulates dysbiosis of intestinal flora in C57BL/6 mice

In this study, a rice starch–nobiletin (NOB) complex with well digestion-resistance by in-situ extrusion was chosen as a supplementary diet to protect against ulcerative colitis (UC) induced by dextran sulfate sodium (DSS) in mice. After oral administration, the complex alleviated colon damage caused by DSS, decreased serum levels of proinflammatory cytokines and colon oxidative stress, and improved the expression of tight junction proteins. Meanwhile, the complex may modify the gut microbiota by increasing its diversity and promoting potentially beneficial bacteria, as well as boosting short-chain fatty acid levels. Correlation analysis further revealed that proinflammatory cytokines and other injury factors were negatively related to Firmicutes and Verrucomicrobiota (phylum level), as well as Lactobacillus and Akkermansia (genus level). Overall, our results show that the rice starch–NOB complex protects intestinal barrier dysfunction in UC and may be a healthy addition to rice starch diets.