Taxol partitioning in two-phase plant cell cultures of Taxus brevifolia

An accumulation phase for taxanes was evaluated for its effect on growth and production kinetics in Taxus brevifolia cell cultures. The second phase, tricaprylin, is an eight-carbon triglyceride that favorably partitions taxol secreted into the medium. Cell growth was generally unaffected by the presence of tricaprylin and a moderate increase in taxol synthesis over a 4-week period was observed. Adjustments of the medium pH can be used to obtain significantly higher partitioning (at higher pH), but this adversely affects the cell productivity with a net loss in taxol production for pH values greater than 7.5. Nevertheless, in situ liquid partitioning provides a clean reservoir for taxane separation in otherwise normal cell culture that can also be easily sampled and replaced during a semi-batch or continuous culture.