This research first reports the tyrosinase inhibition and mechanism of Leucrocin I and its modified peptides (TILI-1 and TILI-2). Docking simulation showed that these peptides were predicted to bind and interact to active site of tyrosinase and exhibited the possibility to promote tyrosinase inhibition. Therefore, these peptides were synthesized, and their inhibitory activity was investigated. The results showed that the highest tyrosinase inhibition was achieved by TILI-2 followed by TILI-1 and Leucrocin I. A Lineweaver–Burk plot indicated that Leucrocin I exhibited mixed type characteristics, while its modified peptides exhibited competitive inhibition. Based on the greatest tyrosinase inhibition, TILI-2 was selected for further study. TILI-2 showed irreversible inhibition with two-step inactivation. Additionally, Leucrocin I and its modified peptides showed no toxicity toward B16F1 and HaCaT cells and decreased melanin and tyrosinase content in B16F1 cells. These results suggest that these peptides are promising peptides for the treatment of hyperpigmentation.

这项研究首先报道了酪氨酸酶对白花胶Ⅰ及其修饰的肽（TILI-1和TILI-2）的抑制作用和机理。对接模拟表明，这些肽被预测与酪氨酸酶的活性位点结合并相互作用，并具有促进酪氨酸酶抑制的可能性。因此，合成了这些肽，并研究了它们的抑制活性。结果表明，TILI-2，其次是TILI-1和Leucrocin I达到了最高的酪氨酸酶抑制作用。Lineweaver-Burk图表明Leucrocin I表现出混合型特征，而其修饰肽表现出竞争性抑制作用。基于最大的酪氨酸酶抑制作用，选择TILI-2进行进一步研究。TILI-2表现出不可逆的抑制作用，具有两步失活。另外，Leucrocin I及其修饰的肽对B16F1和HaCaT细胞无毒性，并且B16F1细胞中的黑色素和酪氨酸酶含量降低。这些结果表明这些肽是用于治疗色素沉着过度的有前途的肽。