Abstract
Chlorogenic acid (CGA) is an active ingredient widely found in plants and has been shown to have potential blood-glucose-lowering effects. However, the research on the efficient extraction processes of CGA from sweet potatoes and its systematic mechanisms underlying hypoglycemic effects is still insufficient. This study optimized the extraction of CGA from various sweet potato parts and varieties using ethanol, and predicted the hypoglycemic mechanism of sweet potato leaves via network pharmacology and molecular docking. The efficacy of the leaf extracts was demonstrated through the in vitro inhibition of hepatic glucose output, accompanied by minimal cytotoxicity, and was further validated in an acute mouse model. The results demonstrated that the optimal extraction conditions were an ethanol concentration of 65.48%, a liquid-solid ratio of 39.00 mL·g(-1), an ultrasonic time of 50.00 min, and a temperature of 45 °C. The final extraction yield of CGA crude extract was 3.54%, with the highest content in sweet potato leaves, suggesting a multi-target synergistic mechanism of action for sweet potato leaves. Further in vitro experiments indicated that the CGA crude extract can exert hypoglycemic effects by inhibiting hepatic gluconeogenesis. In conclusion, the study lays a foundation for the further purification and utilization of sweet potato CGA, and establishes a theoretical basis for the development of sweet potato leaf resources as hypoglycemic functional ingredients.