These sources include the bark from various Taxus species such as, for example, Taxus brevifolia, Taxus baccata, Taxus yunnanensis, Taxus chinensis and Taxus wallichiana, plant material such as needles and twigs from various Taxus and Cephalotaxus species, extracts of biomass containing a complex mixture of taxane type compounds, as well as in the downstream purification of cephalomannine and 7-ep