Abstract: Based on less content of active ingredients of Chinese herb, crystal ingredients jamming pipeline, and so on, we took extractof ginkgo biloba L. as experimental material to investigate the effect of extracting and crystallizing pressure, temperature and timeon the purity of ginkgolides extracted and crystallized by supercritical CO2 via single factor experiments. The results showed thatextracting and crystallizing pressure 20MPa, temperature 55℃, time 90min, the purity of ginkgolides was more than 85%.

Key words: supercritical CO2, extracting and crystallizing, ginkgolide, purity, gradient distribution