Identification and molecular mechanism of novel tyrosinase inhibitory peptides from collagen

This study aimed to identify novel tyrosinase inhibitory peptides from collagen of donkey by combining in silico screening with in vitro activity verification, and to elucidate inhibition mechanism based on molecular docking and molecular dynamics simulation. Three tripeptides, that is, Asp-Gly-Leu (DGL), Gly-Ala-Arg (GAR), and Ser-Asp-Trp (SDW) were identified and exerted potent tyrosinase inhibitory activities, with IC50 values of 0.47 ± 0.01 mM, 1.13 ± 0.04 mM, and 2.08 ± 0.01 mM, respectively. Each of three identified peptides had hydrophobic amino acids and could stably and closely bind with the active pocket of tyrosinase. Hydrogen bonds played the most important roles in impacting the structure stabilities of the peptide-tyrosinase complexes. Moreover, His85, His244, His259, and Asn260 were the key residues to drive the interactions between the peptides and tyrosinase. Overall, collagen-derived peptides DGL, GAR, and SDW from donkey had great potential as tyrosinase inhibitory peptides. PRACTICAL APPLICATION: This study has suggested that three tripeptides DGL, GAR, and SDW derived from collagen of donkey have potent tyrosinase inhibitory activity. These novel collagen-derived peptides had great potential to be applied as tyrosinase inhibitory peptides to prevent and improve hyperpigmentation disorders and other tyrosinase-related problems in the food industry. And this work is expected to provide a theoretical basis for the development of novel, safe, and effective tyrosinase inhibitory peptides.