Abstract: To improve the antioxidant capacity of bovine collagen-derived peptides and to identify novel peptides with antioxidant properties, this study employed ultra-high pressure (UHP) pretreatment followed by enzymatic hydrolysis with alkaline protease. The resulting peptides were analyzed for their antioxidant capacity, structural properties, molecular mass distribution, and amino acid sequences. It was found that UHP-assisted enzymatic hydrolysis increased the antioxidant activity and surface hydrophobicity of collagen peptides compared with conventional enzymatic hydrolysis, resulting in exposure of more hydrophobic groups and increasing hydrophobic amino acid content; morphological analysis showed that more amorphous structures were produced by UHP, resulting in smaller molecular masses and smaller peptide particles. Following isolation and purification, four novel antioxidant peptides with properties were identified. These findings provide theoretical support and technical reference for the production of food-derived antioxidants.

Key words: ultra-high pressure pretreatment; collagen-derived antioxidant peptide; structural characterization; sequence identification; molecular docking