银杏叶中聚戊烯醇含量及其季节性变化

The samples of \%Ginkgo biloba \%L. leaves of 30 years old tree were collected from April to November in Nanjing and were extracted with petroleum ether (60～90℃), purified with silical gel and analysed by HPLC. The results showed that the content of polyprenols in \%Ginkgo biloba \%leaves grew up month by month, while the yellow leaves had the highest content about 1.1% in fall. The main polyprenol was C\-\{85\}, about 38% content and the next was C\-\{90\}, about 32%. On the other hand, by analysing the leaves of young tree of 3～5 years old in Pizhou city, Jiangsu Province collected in fall, the main was polyprenol of C\-\{90\}about 34%～35%, the second was polyprenol of C\-\{85\}about 24%～25%, compared with the leaves of old tree collected at the same time, the total content of polyprenols in the leaves of young tree was higher.