L-半胱氨酸作为化妆品美白添加剂的作用机理

酪氨酸酶(EC 1.14.18.1)是黑色素形成的关键酶,其抑制剂的研究是当前美白添加剂研究的热点.研究了L-半胱氨酸(L-Cys)对蘑菇酪氨酸酶和小鼠B16黑色素瘤细胞粗提的酪氨酸酶的抑制效应,实验结果表明,L-Cys对2种来源的酪氨酸酶有较强的抑制作用,其半效抑制浓度分别为1.75,15 μmol/L.对小鼠B16黑色素瘤细胞粗提的酪氨酸酶的抑制主要表现为显著延长酶促反应的迟滞时间,同时显著降低酶的活力.进一步对L-Cys在细胞毒性方面进行了研究,结果表明,在200 μmol/L浓度下,L-Cys对小鼠黑素瘤细胞B16的生长未显示出明显影响,对细胞状态、代谢MTT的能力、细胞增殖率等均无影响,无明显细胞毒性,是一种有潜力的增白剂,为L-Cys作为美白添加剂提供了依据.

Study on the Mechanism of L-Cysteine as a Whitening Cosmetic Additive

Tyrosinase(EC 1.14.18.1)is a key enzyme involved in the melanin biosynthesis.Nowadays,tyrosinase inhibition has become a hot spot on research of whitening cosmetic additive.In this paper,the effects of L-cysteine(L-Cys) on the activity of tyrosinase from both mushroom and mouse B16 melanoma cells were studied.The results showed that L-Cys could remarkably prolong the lag time and inhibit the activity of tyrosinase extracted from B16 cells,and the concentration for L-Cys leading to 50% tyrosinase activity lost (IC50) was 1.75 μmol/L and 15 μmol/L,respectively.Furthermore,the cells toxicity of L-Cys were assessed.The results showed that L-Cys has no obvious influence in cellular morphology,growth rate,metabolism of thiazole blue (MTT) of B16 melanoma cells,indicating that L-Cys is safe for using as a potential cosmetic additive.This research provided a basis for the usage of L-Cys as whitening cosmetic additive.