The concentrations of ginkgolides A, B, and C, and bilobalide were determined in the
leaves of 3 different Dutch Ginkgo biloba trees from late spring until late autumn 1990. The concentration versus harvest time
plots were roughly the same for all the compounds in each of the 3 trees. Concentration
was lowest in spring and then gradually increased until a maximum in late summer or
early autumn was reached. Thereafter the concentration declined until leaf fall. The
difference in ginkgolide and bilobalide content between the 3 trees was very high.
For ginkgolide B, the pharmacologically most potent compound, the maximum concentration
was less than 3, 68 and 204 ppm respectively. Possible reasons for these differences
and consequences for phytotherapy are discussed briefly.
Ginkgo biloba
- ginkgolides A, B, C and J - bilobalide - concentration - seasonal variations
