Occurrence of 14-hydroxylated taxoids in the plant in vitro cell cultures of different yew species (Taxus spp.).

This is the first study to show that the formation of 14ß-hydroxylated derivatives of taxa-4(20),11-diene is a specific feature of in vitro cultured dedifferentiated yew cells that distinguishes them from intact plant cells. This may be due to a lower toxicity of the 14-OH taxoids for proliferating plant cells compared to the 13-OH derivatives.