Abstract: Based on low content of active ingredients of Chinese herb, and the principle of supercritical dilute solution extractionand the fundamental principle of solvent extraction, we prepared the extract of ginkgo biloba L. as experimental material toinvestigate the effect of ratio of liquid to solid material, extraction temperature and extraction time on pre-treatment of supercriticalCO2 extracting and crystallizing ginkgolides via single factor experiments. The results showed with that 20 times more volumesolvent (40% acetone-60% ether) the optimum conditions were: 45℃ extraction temperature, extraction 2 times and 4h everytime and ratio of extraction more than 95%, the ginkgolide yield was more than 16%. The method of determination was extractand steady.

Key words: supercritical CO2, ginkgolide, extracting and crystallizing, extraction