LEP and diabetes mellitus: Mechanistic studies identified propionic acid as a key mediator, which may exert its effects by promoting leptin (LEP) secretion and activating the hepatic AMP-activated protein kinase (AMPK) pathway, thus suppressing hepatic gluconeogenesis.<h4>Conclusion</h4>This research identifies PP III as the principal hypoglycemic fraction of PP, providing mechanistic insights and preclinical evidence supporting its potential application as a functional food, health supplement, or pharmaceutical agent for diabetes management.