The stimulation of taxol production in Taxus brevifolia by various growth retardants

Abstract

We have shown that chlorocholine chloride (CCC), succinic acid, 2,2-dimethylhydrazide (Alar ®) and tetramethylammonium bromide (TMAB) stimulate [ 14C]acetate incorporation into taxol in intact pieces of the inner bark of Taxus brevifolia (Pacific yew). Both CCC and Alar also stimulated taxol production in yew logs as measured by the incorporation of [1- 14C]acetate into [ 14C]taxol. An increase in taxol accumulation also occured in silica gel placed under flaps of yew trees in the forest treated with these two compounds. CCC also caused an increase, in an 8-week treatment period, of recoverable taxol from Pacific yew bark in a forest setting. CCC, alar and TMAB are all known as growth retardants, but may cause an effect on taxol biosynthesis via an inhibition of sterol biosynthesis.