A ferric ion-reducing system and three free radical systems were used to evaluate the radical-scavenging capacity and antioxidant activity of collagen peptides from Lophius litulon skin in vitro. The peptide components were separated by ultrafiltration and the fraction with the highest hydroxyl radical scavenging activity in vitro was obtained. In addition, aged mouse models were constructed and determined for SOD, CAT, GSH-Px, MDA and Hyp contents in the skin after oral administration of the screened fract...