Extraction, purification by solid-phase extraction and high-performance liquid chromatographic analysis of taxanes...

Needles from ornamental yews (Taxus spp.) are known to contain significant amounts of the anticancer agent Taxol (paclitaxel), as well as other analogous taxane compounds. Methanol extracts the taxanes from the needles efficiently, but the crude methanolic extract contains large amounts of co-extractives in addition to the taxanes of interest. The crude extract may be fractionally partitioned using C18 solid-phase extraction (SPE), permitting the collection of a fraction in which the taxanes elute quantitatively. This fraction can then be analyzed directly by means of high-performance liquid chromatography. We have successfully scaled-up the quantity of crude extract partitioned by means of the SPE technique, using larger SPE cartridges prepared in our laboratory as well as using Empore extraction disks. SPE using the Empore disks permits us to collect large quantities of the taxane fraction for studies on its cytostatic effect on non-mammalian eukaryotic cells.