黑面神提取物对酪氨酸酶的抑制动力学  

Inhibitory Kinetics of Extracts from Breynia Fruticosa on Mushroom Tyrosinase

作　　者：卢武林[1] 罗红军[1] 李慧[1] 罗文鸿[1] 

机构地区：[1]汕头大学医学院分析测试实验室,广东汕头515041

出　　处：《汕头大学医学院学报》2011年第4期204-206,210,共4页Journal of Shantou University Medical College

基　　金：广东省自然科学基金团队资助项目(9351507102000-001)

摘　　要：目的:研究黑面神提取物对酪氨酸酶活性的影响,为色素增加性皮肤的治疗提供实验依据。方法:采用酪氨酸酶催化氧化左旋多巴速率法体外测定酪氨酸酶活力。以Lineweaver-Burk曲线推导出黑面神提取物对酪氨酸酶的抑制效应及动力学。结果:导致酪氨酸酶活力下降50%的黑面神提取物正丁醇部分浓度约为0.8 mg/mL,对游离酶和酶-底物复合物的抑制常数分别为(0.7±0.0),(1.4±0.1)mg/mL。结论:黑面神提取物正丁醇部分对酪氨酸酶抑制机制为可逆的混合型抑制。Objective：To study the effect of breynia fruticosa on the activity of mushroom tyrosinase,and to provide experimental evidence for the treatment of hyperpigmentation disorders.Methods：Tyrosinase activity was estimated by oxidation rate of L-dopa.The inhibitory effect of the extracts from breynia fruticosa on the activity of mushroom tyrosinase and inhibition kinetics were deduced from the Lineweaver-Burk plots.Results：The inhibitory concentration of the n-butanol fraction of the ethanol extracts from breynia fruticosa leading to 50% enzyme activity lost was estimated to be 0.8 mg/mL.The inhibition constants for the n-butanol fraction binding free enzyme and substrate-enzyme were（0.7±0.0）and（1.4±0.1）mg/mL respectively.Conclusion：The n-butanol fraction from breynia fruticosa is a reversible mixed-type inhibitor for the oxidation of L-dopa.

关 键 词：黑面神 酪氨酸酶 抑制作用 动力学 

分 类 号：R285.5[医药卫生—中药学]