Preparative chromatographic separation of taxol from yew trees

Taxol shows promise for the treatment of a variety of human cancers, including leukemia and certain ovarian, breast, and lung tumors. In this work, the separation of taxol from Korean Yew tree was studied with solvent extraction and liquid chromatography. The content of taxol in the tree was analyzed to be 0.064 mg/g of dry powder. Methanol was used to extract taxol and the resulting extract was concentrated by the partition of water and methylene chloride. In the pretreatment step with open tubular chromatography, the first mobile phase was methylene chloride/acetone, 97/3 vol.% and the second mobile phase methylene chloride/acetone, 75/25 vol.%. The sample containing taxol was further purified by varying the composition of solvent, flow rate, and injection amount in analytical chromatography. In a semi-preparative column (3.9 x 300 mm) with larger particle sizes the mobile phase composition was hexane/2-propanol/methanol, 90/4/6 vol.% in isocratic mode. Based on the mobile phase composition with 16 mL/min of mobile phase flow rate in a preparative column (22 x 250 mm), 2.41 mg of purified taxol was obtained in a single run.