银杏叶黄酮、萜内酯含量的季节性变化及适采期研究

Studies on seasonal variation of flavonoids, ginkgolides and the optimum harvest time on leaves of ginkgo

为了掌握银杏叶品质和产量的形成规律 ,对银杏叶黄酮、萜内酯含量的季节性变化及适宜采收期进行了研究 ,结果表明 ,5月份前 ,银杏新梢幼叶中黄酮含量最高 ,达到 2 74 % ;随叶龄增大黄酮含量迅速降低 ,到 6月中旬达到最低 ,为 1 0 5% ;7～ 9月银杏叶黄酮含量有所增加。银杏萜内酯含量和单叶干重随叶龄增大而增加 ,到 8～ 9月处于最高水平 ,分别为 0 2 5%～ 0 2 6 %和0 30 %～ 0 32 %。

Seasonal variation of flavonoids, ginkgolides and the optimum harvest time on the leaves of ginkgo tree were studied. The results showed that the content of flavonoids was the highest in young leaf by 2 74% before May. Thereafter it dropped in the next two months, with the lowest content by 1 05%. Then it came to increase gradually from July. With the development of the leaf the content of ginkgolides and dry weight of per leaf increased to the highest level from August to September and they were 0 25%-0 26% and 0 30%-0 32% respectively.According to the results the optimum harvest time of ginkgo leaf was determined.