An on-line detection system for screening small molecule inhibitors of α-Amylase and α-Glucosidase in Prunus mume

•An on-line system was established to screen α-amylase and α-glucosidase inhibitors.•> 20 compounds from Prunus mume strongly inhibited the two enzymes.•The activities were validated by inhibitor-enzyme interactions in mechanistic studies.•Inhibition mechanisms were revealed by fluorescent quenching and molecular docking.