Identification of Tyrosinase Inhibitory Peptides from Sea Cucumber (Apostichopus japonicus) Collagen by in silico Methods and Study of their Molecular Mechanism

Aims: Identify novel tyrosinase inhibitory peptides from sea cucumber (Apostichopus japonicus) collagen using in silico methods and elucidate the molecular interaction mechanism. Background: Tyrosinase is a key enzyme in the melanin biosynthesis pathway, to restrain melanin production and reduce the appearance of associated skin diseases, inhibition of tyrosinase activity is one of the most effective methods. Objective: The collagen from Apostichopus japonicus, which consists of 3,700 amino acid residues, was obtained from the National Center for Biotechnology Information (NCBI) as the accession number of PIK45888. Method: Virtual hydrolyzed method was used, and the peptides generated were compared to the previously established BIOPEP-UWM database. In addition, peptides were examined for their solubility, toxicity, and tyrosinase-binding capacity. Result: A tripeptide CME with optimal potential inhibitory activity against tyrosinase was identified, and its inhibitory activity was validated by in vitro experiments. The IC50 value of CME was 0.348 ± 0.02 mM for monophenolase, which was inferior to the positive control peptide glutathione, while it had an IC50 value of 1.436 ± 0.07 mM for diphenolase, which was significantly better than glutathione, and the inhibition effect of CME on tyrosinase was competitive and reversible. Conclusion: In silico methods were efficient and useful in the identification of new peptides.