Anti-photoaging activity of cod peptides: structural characterisation and clinical validation

, and HAS-1/2/3, and inhibiting ROS generation and over-activation of MMP-1/3 in UVA-damaged cells, with CP having the most significant effect. Mass spectrometry analysis showed that CP, together with TP and BP, shared the characteristics of N-terminal regions enriched in hydrophobic residues and C-terminal regions rich in hydrophobic and basic amino acids; in addition, CP presented a higher proportion of N-terminal electronically characterized amino acids and aromatic amino acids, potentially contributing to its superior antioxidant capacity and collagen metabolism regulation ability. Further double-blind placebo-controlled clinical trials confirmed that continuous oral administration of CP for 8 weeks significantly improved skin hydration, elasticity, and wrinkle reduction. Collectively, CP emerged as the most promising anti-photoaging candidate among the five collagen peptides, and its structure-function characteristics and clinical efficacy provide a robust foundation for its application and development in the field of functional foods.