天然产物对酪氨酸酶的抑制及抑制机理的研究进展

Development about mechanism of natural material inhibiting the tyrosinase

介绍了酪氨酸酶的结构及酶促褐变机制;重点阐述了对酪氨酸酶抑制的特征及抑制机理。酪氨酸酶的抑制特征为可逆抑制,分为竞争性、非竞争性、混合型及缓慢结合型4种。其抑制的主要机理分别为:底物类似物结合酶的活性中心从而抑制酶活性;抑制剂与酶活性中心以外的氨基酸残基结合及抑制剂对过氧自由基的清除作用;抑制剂对酶活性中心的内源桥基的影响;抑制剂与酶快速形成复合物,此后经历一个缓慢的可逆异构化过程。

The structure of tyrosinase and browning mechanism provoked by tyrosinase was introduced,while the character and mechanism for inhibition of tyrosinase was reviewed in detail. The inhibition is characterized in reversibility, including four types-competitive,non-competitive,mixed and slow-binding.The mechanism of inhibition can be described respectively as: the substrate analogues bind active center of tyrosinase, the inhibitors bind the amino acid residual group besides the active center and remove the peroxide free radicals, inhibitors influence the interior bridge of active center of tyrosinase, enzyme and inhibitor form complex rapidly. After that,it undergoes a slow reversible isomerization process.