Preparation and characterization of duck liver-derived antioxidant peptides based on LC-MS/MS, molecular docking, and machine learning

In this study, 4 novel duck liver-derived bioactive peptides with high antioxidant capacity were prepared by fermentation, RP-HPLC purification, LC-MS/MS identification, molecular docking, and machine learning. The molecular docking results demonstrated their antioxidant power mainly by forming hydrogen bonds between their amino acid residues and free radical molecules. Machine learning further confirmed their ACE inhibitory and antioxidant effects. Moreover, in H2O2-induced HepG2 oxidative damage cell models, they could increase the activities and mRNA expression levels of intracellular antioxidant enzymes (SOD, CAT, and GSH-Px), and reduce the content of malondialdehyde (MDA) and reactive oxygen species (ROS) accumulation, thereby inhibiting intracellular oxidative damage. It has important implications for the high-value utilization of duck liver byproducts and food-derived bioactive peptides drinks development.