Ultrasound‐assisted degradation of polysaccharides from sweet corn cob can regulate gut microbiota and activate multiple pathways via the gut–liver axis to alleviate T2DM in mice

BACKGROUND The prevalence of type 2 diabetes mellitus (T2DM) has been rising in recent years, prompting interest in natural plant polysaccharides for their ability to mitigate the disease. To enhance its bioactivity, a degraded polysaccharide from sweet corn cob with ultrasonic‐assisted enzymatic method (UE‐DSCCP‐A) was prepared, and its structure was also characterized. Furthermore, the significant alleviation effect of UE‐DSCCP‐A on T2DM has been explored and examined. RESULTS The results showed that UE‐DSCCP‐A was primarily composed of glucose, and with a molecular weight of 12.87 kDa. In vivo experiments showed that fasting blood glucose levels in T2DM mice was effectively reduced by UE‐DSCCP‐A. Additionally, hepatic glucose metabolism could also be regulated by UE‐DSCCP‐A through phosphoenolpyruvate carboxykinase (PEPCK) and glucose‐6‐phosphatase (G6Pase) expression. T2DM‐induced hepatic oxidative stress injury and inflammatory responses could also be regulated by UE‐DSCCP‐A through the Nrf2/HO‐1 and TLR4/MyD88/NF‐κB pathways. Moreover, the gut microbiota in T2DM mice was positively influenced, with an increase in beneficial bacteria such as Lactobacillus , Faecalibaculum , Lachnospiraceae_NK4A136_group , Rikenellaceae_RC9_gut_group , and Alistipes , and a decrease in Romboutsia , Desulfovibrio , and Corynebacterium_1 . CONCLUSION This study provided evidence that UE‐DSCCP‐A can regulate T2DM‐induced liver damage and gut microbiota imbalances through the gut–liver axis, and the findings may act as a reference for the application of UE‐DSCCP‐A in functional food.