Purification of Ginkgo biloba Extract by Antisolvent Recrystallization

The content of flavonoids in Gingko biloba extract (GBE) could be increased by antisolvent recrystallization (ASR) using ethanol as solvent and hexane as antisolvent. By means of the single-factor method, the effect of main factors on the content of flavonoids in purified GBE was investigated. Under optimal conditions, the content of flavonoids and ginkgo terpene lactones in purified GBE could be significantly enhanced. In addition, the content of total ginkgolic acid in purified GBE was reduced. The morphologies of raw and purified GBE were characterized by scanning electron microscopy. It was found that the particle size of purified GBE was much smaller than that of raw GBE. At the same time, the saturated solubility could be improved by more than four times.