文冠果壳皂苷提取物抑制酪氨酸酶活性的研究

分别采用70％的乙醇溶液、蒸馏水2种浸提液提取文冠果壳中的皂苷,并测定其含量以确定最佳提取溶剂.通过对酪氨酸酶催化L-多巴氧化速率的测定研究了文冠果壳粉的乙醇提取液对体外酪氨酸酶活性的抑制作用.结果表明,皂苷粗提液对酪氨酸酶的抑制率与浓度呈非线性变化,随着浓度的增加,抑制剂对酪氨酸酶活性的抑制率先增加后趋于平稳.当皂苷质量浓度为0.36 mg/mL,抑制率可达到64.6％.通过酶抑制作用的Lineweaver-Burk图,分析结果显示,文冠果壳皂苷粗提液对酪氨酸酶的抑制作用类型为非竞争性抑制.上述研究为进一步开发文冠果壳中的美白成分提供了依据,同时又实现了废物利用,提高了农产品的经济价值.

Inhibitory Effect of Saponin Consituents from Xanthoceras Sorbifolia Nutshell on Tyrosinase

This thesis discusses the extract of Xanthoceras Sorbifolia Nutshell which is abstracted by refluxing with 75% (v/v) ethanol or distilled water, in order to measure saponins" content and determine the best extraction solvent. The ethanol extract of nutshell restrains the activity of the vitro tyrosinase, through the research of the rate of tyrosinase catalyzed L-DOPA oxidation. The result indicates that the inhibition rate of the saponins coarse extract effects tyrosinase"s activity presented non-linear changes with the concentrations. The inhibition rate increases and then levels off, with the increasing of extract concentrations. The inhibition rate will reach 64.60% when the saponins" concentrations are 0.36mg/ml. The inhibition type of saponins of the bunge" nutshell coarse extract that effects tyrosinase is noncompetitive inhibition, through the Lineweaver-Burk chart which shows the inhibition of the enzyme. The above study provides a basis for further development of the whitening ingredients in the nutshell. At the same time the study achieves the use of waste and improves its economic value of agricultural products.