甘草总皂苷生物转化与抑制酪氨酸酶活性研究

On Biotransformation of Total Saponins of Glycyrrhiza and Inhibition of Tyrosinase Activity

目的:采用不同方法对甘草皂苷进行生物转化,同时进行抑制酪氨酸酶活性实验。方法:采用水作为媒介提取甘草中的总皂苷,再采用D101大孔树脂进行富集,得到甘草总皂苷有效成分;再分别采用蜗牛酶、酵母菌、黑曲霉对甘草总皂苷进行生物转化,以HPLC作为测定仪器,测出甘草苷转化为甘草酸铵的量。同时采用体外抑制酪氨酸酶活性的试验来比较各个不同生物转化液的活性大小。结果:以甘草苷、甘草酸铵为对照品,得出两者的标准曲线:Y=2926525.09X+1632.2(r=0.99996),Y=659561X+33746(r=0.99998),结果表明甘草苷和甘草酸铵分别在0.4920~9.8400μg、0.4520~9.0400μg范围内线性关系良好。采用蜗牛酶、酵母菌、黑曲霉对甘草苷进行生物转化,结果显示酵母菌并不能使甘草中的甘草苷转化为甘草酸铵。观察HPLC图谱,蜗牛酶、黑曲霉转化液下的样品在68.13~71.48 min之间出现了甘草酸铵峰。抑制酪氨酸酶试验得出通过3种方法转化后的甘草溶液,其活性顺序为酵母菌>蜗牛酶>黑曲霉。抑制率分别为39.45%、12.41%、9.42%。说明抑制酪氨酸酶活性的物质为总皂苷,并不是其生物转化后的次生苷。结论:甘草总皂苷抑制酪氨酸酶的活性要大于其生物转化后的次生产物,可以很好地进行化妆品的后期开发。

Objective： Saponins of glycyrrhiza was biotransformed with different methods and inhibition of tyrosinase activity was carried out. Methods： Water was used as the media to extract total saponins from glycyrrhiza and D101 macroporous resin was used to enrich the effective fraction of total saponins. Then the biotransformation of total saponins of glycyrrhiza was carried out by using snail enzyme, yeast and Aspergillus niger enzyme respectively. HPLC was used as the measuring instrument to determine the amount of converted ammonium glycyrrhizinate. At the same time, the inhibition of tyrosinase activity in vitro was conducted to compare the different activity of biotransformed fluids. Results： The standard curves were Y=2926525.09X＋1632.2 （r=0.99996）, Y=659561X＋33746 （r=0.99998） by using glycyrrhizin and ammonium glycyrrhizinate as controls, resulting in good linearity of glycyrrhizin and glycyrrhetinic acid in the range of 0.4920 - 9.8400 μg, 0.4520 - 9.0400 μg respectively. The result of biotransformation of glycyrrhizin by snail enzyme, yeast and Aspergillus niger enzyme showed that yeast was unable to convert glycyrrhizin of licorice into ammonium glycyrrhizinate and the ammonium glycyrrhizinate peak appeared between 68.13 min and 71.48 min of the samples converted by snail enzyme and Aspergillus niger enzyme. Tyrosinase inhibition test showed that the activity order of the transformed licorice solution by three enzymes was yeast〉snail enzyme 〉Aspergillus niger enzyme and the inhibitory rates were 39.45%, 12.41% and 9.42% respectively, which indicates that the substance inhibiting tyrosinase activity was total saponin instead of the biotransformed secondary glycoside. Conclusion： The anti-aging activity of total saponins of glycyrrhiza is greater than that of secondary products after biotransformation, and it can be used for the later development of cosmetics.