Supercritical extraction of taxol from the bark of Taxus brevifolia

Abstract

Taxol has been found to be an effective drug for the treatment of ovarian cancer. However, the only current source of this compound is from trees of the Taxus genus and methods need to be developed for its separation from the natural plant source. The extraction of taxol from the ground bark of Taxus brevifolia using supercritical carbon dioxide and carbon dioxide + ethanol mixtures was studied in this work. The extractions were preformed at 318 K and at pressures ranging from 18.07 to 25.79 MPa. It was demonstrated that supercritical carbon dioxide is able to extract taxol from the ground bark, especially at the higher pressures and with the addition of ethanol. The supercritical extractions of taxol were also found to be more selective than a conventional liquid ethanol extraction. Furthermore, a significant portion of the taxol present in the bark could be removed in the supercritical process.