Distribution And Variation Of Taxanes Contents In Natural Taxus Cuspidata

Taxus cuspidata, of the family Taxaceae and genus Taxus, is a valuable survivor from the Quaternary Period. Taxol, a diterpene compound extracted from Taxus plants, is a new, efficient, broad spectrum anti-carcinogen, however, the content of taxol in plants is very small, as the key to the success of the medicine lies in the sufficiency of resources, the protection and regeneration of the Taxus resources have become a major topic of research in the world. In this project, we focused on the secondary metabolites of taxanes in Taxus cuspidata. The results are as follows:1. The content of paclitaxel and cephalomannine have the same change trends with the growth period, in general, from April, the two kinds of material is fluctuation change, and then has been an steady state. The current year, biennial, perennial branches had the highest paclitaxel content in August, September, September, respectively, the highest paclitaxel content was40.08、24.66、19.77μg/g. The current year, biennial, perennial branches had the highest cephalomannine content in July, August, August, respectively, the highest cephalomannine content was25.20、15.52、14.62μg/g. The content of baccatinⅢ and10-DABⅢ changes in fluctuation, and increases from July and August to October. The current year, biennial, perennial branches had the highest baccatinⅢ content in October, the highest baccatinⅢ content was23.59、20.43、20.03μg/g. The current year, biennial, perennial branches had the highest10-DABⅢ content in October, June, October, respectively, the highest10-DABⅢ content was41.13、17.00、24.55μg/g.2. In this project, we investigated the characteristics of the taxane content changes along with increasing age, the DBH of Taxus cuspidata was from1.8cm to72.2cm. The content of paclitaxel increased first and then decreased with age increasing, while the content of cephalomannine decreased with age increasing. In the current-year branches and the biennial branches, there is no significant difference in the contents of baccatinⅢ and10-DABⅢ from trees ages, but in the perennial branches, the contents of baccatinⅢ and10-DABⅢ decreased first and then in creased with age increasing.3. The contents of four kinds of taxanes in female and male yew trees showed the same characteristics, when DBH was larger, male trees contained higher taxanes than female trees, while female trees contained higher baccatinⅢ than male trees when DBH was smaller.4. Trees on sunny slope with the condition that small and medium DBH had higher taxanes than the individuals on shady slope, and trees on shady slope with large DBH had higher taxanes than thoes on sunny slope; trees on mid-slope and on toe slope had higher taxanes than those on the top. Trees on steep gradient contained more paclitaxel and cephalomannine, but less baccatinⅢ and10-deacetyl baccatinⅢ on the contrary; more taxanes were found in the trees at middle altitude, and least in the trees at higher altitude.