Patent ID: 7259268

Claim:
A method of purifying paclitaxel, consisting essentially of: (a) extracting a plant belonging to a Taxus genus, a cell, or a cell culture thereof, with an organic solvent to obtain an extract, and concentrating the extract; (b) adding an organic solvent which is not mixed with water to the concentrate to separate an organic solvent phase and then concentrating; (c) subjecting the concentrate to normal phase chromatography to obtain an eluate; (d) dissolving the eluate in an acetone or dichloromethane followed by adding pentane or hexane to form a precipitate, wherein about 5 to 100 mg of the eluate is dissolved in 1 ml of acetone or dichloromethane, and pentane or hexane is added in an amount such that the precipitate upon subjecting to high performance liquid chromatography yields paclitaxel of at least 99.5% purity; (e) subjecting the precipitate to high performance liquid chromatography; and (f) recovering paclitaxel of at least said purity, wherein the volume ratio of acetone or dichloromethane to pentane or hexane is in a range of 1:3 to 1:20.