Stachyose Enhances Bioavailability of Theaflavins to Activate Glycolipid Metabolism and Fat Thermogenesis in Mice with Consumption of High-Fat Diet

This study investigated the synergistic effects of stachyose and theaflavins (TFs) on bioavailability and antiobesity efficacy in high-fat diet (HFD)-induced obese mice. Coadministration with stachyose (250/500 mg/kg) increased the serum and fecal theaflavin monomer concentrations, relative to TFs alone (100 mg/kg). The cotreatment outperformed individual stachyose or TFs in ameliorating hepatic steatosis, weight gain, dyslipidemia, oxidative stress, and inflammation in obese mice, which also caused the decrease in the Firmicutes/Bacteroidetes ratio by 79.5%, an increase in beneficial <i>Bifidobacterium</i> and <i>Akkermansia</i>, the reduction of cholic acid by 80%, and the elevation in total short-chain fatty acids by 29.9% at 500 mg/kg stachyose. Additionally, the combination upregulated uncoupling protein 1 (UCP1) expression in white and brown adipose tissue, thereby promoting browning and thermogenesis. Our findings demonstrate that the combined stachyose can enhance bioavailability and antiobesity efficacy of TFs by inhibiting intestinal degradation, preserving structural stability and modulating gut microbiota and metabolites.