龙井乙醇提取物对酪氨酸酶活性的抑制作用

Inhibitory mechanism of ethanol extracts from longjing on tyrosinase activity

以龙井、柿叶、贡菊和银杏叶为原料,用L-酪氨酸和L-DOPA为底物测定各原料的乙醇提取物对酪氨酸酶的抑制作用。结果表明,四种原料的乙醇提取物对酪氨酸酶均有一定的抑制作用,以龙井的抑制率最高,当浓度达到4mg·mL-1(以生药计)时,抑制率为30.36%,其IC50值为7.5mg/mL。龙井乙醇提取物对酪氨酸酶的抑制作用属于可逆过程,其抑制类型为混合型,KI为3.1,KIS为9.3。

Longjing, persimmon leaf, florists chrysanthemum and ginkgo biloba were used as experimental materiaLs.The inhibitory of these ethanol extracts on tyrosinase activities were examined with L-Tryosine and L- DOPA as substrate.The results showed that the ethanol extracts from 4 drugs all had obvious inhibitory activity on tyrosinase,the strongest effects occurred with Iongjing ethanol extract,the maximum inhibition rate was 30.36% at concentration of 4mg ·mL^-1, IC50 was 7.5mg/mL. Ethanol extracts from Iongjing showed reversibly inhibitors to tyrosinase and the type of inhibition belonged to be mixed-type,KI was 3.1 and KIS was 9.3.