Virtual Screening of Activity Evaluation of Dipeptidyl Peptidase-Ⅳ Inhibitory Peptides in White Beer

This study aimed to establish a method for rapid screening of dipeptidyl peptidase-Ⅳ (DPP-Ⅳ) inhibitory peptides from white beer. The amino acid sequences of polypeptides were identified by ultrahigh performance liquid chromatography-quadrupole electrostatic field orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap-MS²) with the De novo software. In total 68 polypeptides were determined with high confidence, and their biological activity was evaluated using Peptide Ranker. Of these, four were selected for their scores greater than 0.5 to predict their potential DPP-Ⅳ inhibitory activity. Meanwhile, another 13 peptides with DPP-Ⅳ inhibitory activity were selected according to previous reports. The absorption, metabolism and toxicity of these 17 peptides were predicted and they were evaluated by molecular docking. Finally, two potential DPP-Ⅳ inhibitory peptides, VPFPHTP and LAKLQR, were selected. The molecular docking results showed that both peptides could bind DPP-Ⅳ tightly by hydrogen bonding and hydrophobic interaction. The peptides were found to have obvious in vitro DPP-Ⅳ inhibitory activity.