Exploring the phytochemicals and inhibitory effects against α-glucosidase and dipeptidyl peptidase-IV in Chinese pickled chili pepper: Insights into mechanisms by molecular docking analysis
Meiqi Li, Xi Bao, Xueting Zhang, Hongbing Ren, Shengbao Cai, Xiaosong Hu, Junjie Yi
Abstract
The present work investigated the effect of 90 days’ traditional fermentation on phytochemicals and inhibition towards α-glucosidase and dipeptidyl peptidase-IV (DPP-IV) of pickled chili pepper, and clarified their possible mechanisms based on molecular docking analysis. The results show that traditional fermentation significantly enhanced the inhibition for α-glucosidase but reduced the inhibitory effects towards DPP-IV (P < 0.05), especially fermented for 42 days. In pickled chili peppers, a total of 12 phytochemical compounds were characterized and quantified, of which kaempferol-3-O-rutinoside, kaempferol-3-O-glucoside, apigenin, luteolin, and luteolin glycosides increased significantly after fermentation (P < 0.05). Among the compounds, luteolin showed the highest inhibition against α-glucosidase and isorhamnetin-3-O-glucoside exhibited the strongest inhibition capacity towards DPP-IV. Molecular docking results indicated luteolin, apigenin, and isorhamnetin-3-O-glucoside could effectively interact with crucial amino acid residues of α-glucosidase, while isorhamnetin-3-O-glucoside and isoschaftoside could effectively interact with the key amino acid residues of DPP-IV.