Novel bioactive peptides from ginkgo biloba seed protein and evaluation of their -glucosidase inhibition activity

The inhibition of alpha-glucosidase activity has been recognized as an effective approach for treating type 2 diabetes mellitus (T2DM). In recent years, much emphasis has been placed on identifying peptides with alpha-glucosidase inhibitory activity and elucidating the mechanisms underlying their inhibitory effect in treating T2DM. This study aims to identify peptides with good alpha-glucosidase inhibitory activity from the hydrolysate of ginkgo biloba seed cake protein isolate (GCPI) using in silico screening. It was found that the hydrolysate from Alcalase exhibited the strongest inhibitory effect on alpha-glucosidase (IC50 12.94 +/- 0.37 mg/mL). Three novel peptides with alpha-glucosidase inhibitory activity, i.e., Leu-Ser-Met-Ser-Phe-Pro-Pro-Phe (LSMSFPPF), Val-Pro-Lys-Ile-Pro-Pro-Pro (VPKIPPP) and Met-Pro-Gly-Pro-Pro-Ser-Asp (MPGPPSD), were further identified from the hydrolysate of Alcalase by in silico screening. LSMSFPPF exhibited the strongest inhibitory activity (IC50 454.33 +/- 32.45 mu M), followed by MPGPPSD (IC50 943.82 +/- 73.10 mu M) and VPKIPPP (IC50 1446.81 +/- 66.98 mu M). The pharmacophore model revealed that hydrogen bonds played a critical role in alpha-glucosidase inhibition.