Abstract
This study evaluated tyrosinase inhibition by peptides from locust (Locusta migratoria) protein using enzymatic hydrolysis and ultrafiltration. Peptides with molecular weights below 1 kDa exhibited the strongest inhibitory effect, with a 53.00 ± 0.65 % inhibition rate at 10 mg/mL. Structural analysis revealed that peptides with exposed aromatic amino acids and low α-helix content exhibited enhanced inhibitory activity. LC-MS/MS identified 1108 sequences, mainly from Vitellogenin B and A. Kinetic studies confirmed that the peptides act as mixed-type, reversible inhibitors. Molecular docking identified key interactions, including hydrogen bonds and hydrophobic interactions with critical residues in the enzyme's active site, preventing substrate binding. The peptides exhibited low cytotoxicity in HEK-293 T cells and showed a 37.26 % inhibition rate of tyrosinase in B16 melanoma cells at 2 mg/mL. These findings highlight the potential of locust peptides as effective and safe tyrosinase inhibitors. They could have important applications in cosmetics, pigmentation treatments, and food preservation.