Submitted to: Zeitschrift Fur Naturforschung
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/17/2006
Publication Date: 10/1/2006
Citation: Wang, X., Huang, Y., Mort, A.J., Zeng, Y., Tauer, C.G., Cochran, K.D. 2006. Variation of taxane content in needles of Taxus x media cultivars with different growth characteristics. Zeitschrift Fur Naturforschung. 61c:619-624. Interpretive Summary: Little is known concerning the relationship between the endogenous content of taxol and related compounds in the yew trees with different growth characterization that has the advantage of promoting biomass production. However, it is desirable to identify some cultivars which can combine both high taxane content and fast biomass production. In additional to growth rate of trees, other characteristics like upright or spreading growing form are also important for clippings collection, since upright-growing shoots make mechanical collection easier. In our recent study, we collected needle samples from 17 Taxus x media cultivars with different growth characteristics. The content of four important taxanes (10-DAB, baccatin III, cephalomannine and paclitaxel) was then analyzed by high performance liquid chromatography (HPLC). In this study we identified several Taxus x media upright-growing cultivars with both high taxane content and fast accumulation of biomass. These cultivars make good candidates for direct taxane extraction from clippings, meanwhile, they are also good start materials for alternative production of paclitaxel through biotechnological approaches, including genetic improvement and metabolic engineering.
Technical Abstract: Needles from 17 different Taxus x media cultivars, belonging to 4 groups showing different growth characteristics, were analyzed using high performance liquid chromatography for their content of 10-deacetylbaccatin III, baccatin III, cephalomannine and paclitaxel (Taxol). The 4 Taxus x media cultivar groups are: 1) medium to fast growing and upright form; 2) slow growing and upright form; 3) fast growing and spreading form; and 4) slow growing and spreading form. The purpose of this study was to identify yew cultivars of fast growth rate, upright growth and high taxane content in their needles. The highest content of paclitaxel was found in 'Coleana' of Group 1 (378 microgram/g of the extracted dry weight). Three cultivars in Group 1, 'Coleana', 'Stovekenii' and 'Hicksii', make good candidates for taxane extraction because of their high paclitaxel and 10-deacetylbaccatin III content, fast biomass accumulation and upright growing form. They are also good starting materials for developing alternative methods for the production of paclitaxel and its analog compounds through modern biotechnology approaches.