溴量法测定银杏黄酮的研究

Research of bromine method for Ginkgo biloba extract

银杏黄酮属于多酚类化合物,含有酚羟基,可以和溴分子发生亲电取代反应,据此建立了一种测定银杏黄酮的化学分析方法——溴量法。在实验条件下,研究表明,1分子银杏黄酮可以与5分子溴反应;在一定范围内,盐酸用量、反应时间和溴试剂用量对银杏黄酮与溴的反应系数影响不显著。在对银杏叶提取液浓度1.674 g/L的10次测定的标准偏差为6.48×10-5,加标回收率为98.8%。由此可见,溴量法测定银杏黄酮准确、可靠,可以用于植物提取液中黄酮的分析测定。

Ginkgo biloba extract is a polyphenolic compound, that contains phenolic hydroxyl groups. Then it can react with bromine molecules and the reaction includes electrophilic substitution reaction and elee- trophilic addition reaction. The chemical analysis method, which use bromine method to determine the content of Ginkgo biloba extract, at room temperature, the experimentally measured results is that one molecule Ginkgo biloba extract can react with five molecules bromine. Within a certain range, the influence of reaction time and the amount of HC1 and bromine on the reaction coefficient is not significant. For the Ginkgo biloba extract content is 1. 674 g/L;10 times determination＇ s standard deviation is 6.48 × 10^-5 and the recovery rate is 98.8%. The bromine method for Ginkgo biloba extract is feasible and reliable, suitable for determination of Ginkgo biloba extract content in natural plant extract.