Investigating the contribution of mulberry leaf Fu tea to ameliorating metabolic disorders and remodeling gut microbiota in diabetic mice

Abstract Dysbiosis of the gut microbiota and metabolic disorders contributes to the occurrence of diabetes mellitus. Polyphenols reduce the risk of type II diabetes mellitus (T2DM) by inhibiting α‐glucosidase. Mulberry leaf Fu tea (FM) is a kind of tea obtained by the fermentation of Eurotium cristatum, which is polyphenol‐enriched and has a distinctive aroma, but its antidiabetic mechanism is unclear. In this study, we investigated the polyphenols in the aqueous extract of FM through HRLC‐MS and verified its inhibitory effect on α‐glucosidase in vitro test and finally studied its effect on gut microbiota and short‐chain fatty acids (SCFAs) in diabetic mice. The findings demonstrated that FM supplementation considerably altered gut microbiota abnormalities in diabetic mice, maintained the balance of microflora, encouraged the growth of beneficial microorganisms (Coriobacteriaceae UCG‐002, Dubosiella, Lactobacillus, and Bifidobacterium), and increased levels of acetic acid, propionic acid, and butyric acid. In conclusion, FM can regulate gut microbiota and SCFAs to ameliorate or alleviate T2DM caused by HFD‐STZ. Therefore, FM can also be used as postbiotics to improve T2DM.