Challenges in the isolation of taxanes from Taxus canadensis by fast pyrolysis

The Waterloo Fast Pyrolysis Process (WFPP) was used to determine the feasib ility of extracting taxanes from needles, twigs and whole clippings of Taxu s canadensis. Purification techniques developed for solvent extracts were n ot suitable for achieving analytic chromatographic separation of taxanes fr om pyrolytic lignins and other pyrolysis products as these materials are in much higher quantities in pyrolysis oil than in solvent extracts. A number of separation techniques were attempted including liquid-liquid partitioni ng, silica gel chromatography, adsorption and sodium phenoxide formation. P retreatment of the feedstock by deionization was also attempted. Taxol(R) w as identified in pyrolysis oils of needles and whole clippings with 20% rec overy compared to solvent extraction. Other taxanes were most likely presen t in higher concentrations but could not be analyzed because of interferenc e by phenolic substances. (C) 2001 Elsevier Science B.V. All rights reserve d.