对氰基苯酚对蘑菇酪氨酸酶的抑制作用  

The Inhibitory Effect on Mushroom Tyrosinase by 4-cyanophenol

作　　者：王勤[1] 邱凌[1] 宋康康[1] 郭华云[1] 陈清西[1] 

机构地区：[1]厦门大学生命科学学院细胞生物学与肿瘤细胞工程教育部重点实验室,福建厦门361005

出　　处：《厦门大学学报（自然科学版）》2004年第4期568-571,共4页Journal of Xiamen University：Natural Science

基　　金：福建省自然科学基金(B0110002);教育部留学回国人员科研启动基金资助

摘　　要：报道了对氰基苯酚对蘑菇酪氨酸酶单酚酶和二酚酶活力的抑制效应.结果表明,对氰基苯酚对酪氨酸酶活性的抑制作用表现为可逆抑制作用,对酪氨酸酶的单酚酶的效应主要表现于迟滞时间有明显的延长,对稳态酶活力有显著抑制作用.0.50mmol/L对氰基苯酚使得单酚酶的迟滞时间从18s延长到80s,增大4.4倍,稳态酶活力下降80%.对氰基苯酚对二酚酶的抑制作用显示浓度关系,测定导致酶活力下降50%的抑制剂浓度(IC50)为0.80mmol/L,其抑制作用为竞争性类型,抑制常数KI为0.31mmol/L.通过研究对氰基苯酚对酪氨酸酶的抑制作用机理,试图寻找新型的有增白作用的化妆品添加剂.Tyrosinase (1.14.18.1) is a copper-containing oxidase that catalyzes two distinct reactions of melanin synthesisthe hydroxylation of a monophenol and the oxidation of o-diphenol to the corresponding o-quinone. 4-Cyanophenol was found to inhibit the monophenolase and o-diphenolase activity of mushroom tyrosinase. 4-Cyanophenol inhibited the monophenolase activity. The lag time of the enzyme for oxidation of L-tyrosine extended and the steady-state rate of monophenolase decreased. When the concentration of 4-cyanophenol reached 0.50 mmol/L, the steady-state rate of the enzyme dropped by 80 % of the total activity, and the lag time extended from 18 sec to 80 sec. The inhibition kinetics and mechanism of the diphenolase activity of the enzyme by 4-cyanophenol were farther studied. The results show that the inhibition of 4-cyanophenol is a reversible reaction with remaining enzyme activity. The inhibitor concentrations leading to 50% (IC_(50)) activity lost were estimated to be 0.80 mmol/L for diphenolase. The inhibition kinetics analyzed by Lineweaver-Burk plots was showed that 4-cyanophenol is a competitive inhibitor for the oxidation of L-DOPA, and the inhibition constants were determined to be 0.31 mmol/L for the free enzyme. Comparing with arbutin, 4-cyanophenol is a stronger inhibitor for the diphenolase activity. In this paper, we discuss the writing mechanism of 4-cyanophenol as cosmetic additive.

关 键 词：对氰基苯酚 蘑菇 酪氨酸酶 抑制作用 动力学 黑色素 

分 类 号：Q55[生物学—生物化学] O625.312[理学—有机化学]