连翘不同极性部位对酪氨酸酶活性抑制作用研究

Inhibitory Effect of Different Polar Extracts from Forsythia suspensa on Tyrosinase Activity

目的研究连翘对酪氨酸酶活性的抑制作用。方法将连翘用80%的乙醇水溶液回流提取,得到总提取物,再用不同极性的有机溶剂石油醚、二氯甲烷、正丁醇进一步萃取,得到不同极性部位。将总提取物和各部位浸膏溶于不同体积的溶剂,以L-酪氨酸为底物,加入酪氨酸酶,使终浓度为1.0,0.5,0.2,0.1,0.04 mg.ml-1,测定药物干预前后反应体系在475 nm波长处吸光度值变化,计算各组分对酪氨酸酶活性的抑制率。结果在各组分中,连翘的二氯甲烷部位对酪氨酸酶活性的抑制率最高,当终浓度为1.0 mg.ml-1时,抑制率为57.3%,抑制率随着浓度的增加而升高,其IC50为0.57mg.ml-1;其他组分也均有不同程度的抑制作用,其中正丁醇部位、水溶部位和总提取物随浓度的增加具有双向调节作用。结论连翘具有较好的抑制酪氨酸酶活性的作用,可以抑制黑色素的形成。此实验为进一步研究连翘中酪氨酸酶活性抑制成分及其作用机理提供基础。

ObjectiveTo study the inhibitory effect of Forsythia suspensa on tyrosinase activity. MethodsThe fruits of Forsythia suspensa were refluxing with 80% ethanol to yield the ethanol extract of Forsythia suspensa.The ethanol extracts was then suspensed with water,and fractionationed with petroleum ether,methylene chloride,and normal butanol.These fractions and the ethanol extract of Forsythia suspensa were measured tyrosinase inhibitory effect at concentration of 1.0,0.5,0.2,0.1 and 0.04 mg·ml-1 at 475 nm. ResultsThe methylene chloride fraction of Forsythia suspensa showed the strongest tyrosinase inhibitory effect with the inhibition of 57.3% at 1.0 mg·ml-1.The IC50 value of the methylene chloride fraction of Forsythia suspensa was 0.57 mg·ml-1.The other fractions also showed inhibitory effect on tyrosinase activity.The ethanol extract and normal butanol,water fractions showed diphase regulation function with increasing concentration. ConclusionForsythia suspensa has tyrosinase inhibitory activity,blocking the formation of melanin.The test will provide experimental evidence for further research on the effective of the constituents from Forsythia suspensa and their mechanism of tyrosinase inhibitory effect.