Synthesis of (+) Catechin Penta-acetate by Callus Culture of Himalayan Yew, <i>Taxus wallichiana</i> Zucc.

Abstract

Calli were produced by culturing leaf, stembark, heartwood, root, seed and apical shoot tip explants of <i>Taxus wallichiana </i>from West Bengal Himalayan region. The explants were cultured in dark on a modified Murashige and Skoog (MS) medium supplemented with 3 <img src='/image/spc_char/micro.gif' border=0>g/ml Picloram (4-amino-3, 5, 6-tripicholinic acid), 2 <img src='/image/spc_char/micro.gif' border=0>g/ml 2,4-D (2,4-dichlorophenoxyacetic acid) and 0.25 <img src='/image/spc_char/micro.gif' border=0>g/ml Kinetin. The calli were sub-cultured at every 5-10 weeks interval to maintain the callus lines under similar conditions. A fast growing callus line Tws-179 was selected to study the growth kinetics and chemical constituents. This callus line grew logarithmically (G.I.= 9.28) after an initial lag period of three weeks till it attained the stationary phase in about 8 weeks of culture. During its log phase, the callus line

produced (+) catechin at a level of 0.002 % of fresh callus weight and the acetylated form +) catechin penta-acetate at 0.05% level. Chemical examination of <i>in vivo </i>organs revealed that only (+) catechin at 0.175% was present in the stem bark, while neither (+) catachin nor (+) catachin penta acetate were found in detectable limits in other organs of

<i>T. wallichiana.</i>