Abstract: This study explored the mechanism of probiotics with chromium-rich yeast on Type 2 diabetes in mice. The disease was induced by high-fat diet and intraperitoneal injection of STZ. The fifty mice were divided into five groups. The results showed that Type 2 diabetes is closely related to the imbalance of gut microbiota. The level of the short-chain fatty acids (SCFAs) and the diversity of intestinal microbiota in these mice were significantly reduced, the abundance of some beneficial bacteria was decreased and the abundance of pathogenic bacteria was increased. After intervention, the gut microbiota imbalance was alleviated in drug-treated group, probiotics-treated group and cocktail-treated (using mixture of probiotics and chromium-rich yeast) group. Compared with the probiotics-treated group, the cocktail group showed more significant protective effects, including increase in the abundance of Lactobacillus and SCFA levels, and decrease in glucose level and abundance of Coprococcus and Rikenellaceae-g. Therefore, mixture of probiotics and chromium-rich yeast had more effective and comprehensive protective effects on type 2 diabetes. This study provided a theoretical basis for microbial mixture treatment method as an intervention treatment for Type 2 diabetes.
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