Bioavailability of Ginkgolides and Bilobalide from Extracts of Ginkgo biloba using GC/MS

Abstract

The bioavailability of ginkgolides A, B and bilobalide was studied in rats after single oral administration of 30, 55 and lOO mg/kg Ginkgo extract EGb 761®. The plasma levels of the terpene lactones were measured by a specific GC/MS method. The pharmacokinetics of the mentioned substances were found to be dose-linear. For the lowest dose maximum concentrations were 68, 40 and 159 ng/ml and half-lives 1.7, 2.0 and 2.2h for ginkgolide A, B and bilobalide, respectively. Clearance values ranged from 24.2 to 37.6 ml/min/kg.