Investigation On Difference Of Active Compounds Contents In Taxus Chinensis Var. Mairei And Its Relationship With Ecological Factors

Taxus chinensis var. mairei is a primary key protected wild plant species in China,and is famous for having high efficient anti-cancer ingredients paclitaxel. Naturalrenovation of the plant is poorly and survival distribution is in endangered state,which is effected by its own propagation characteristics, habitat conditions and humanactivities. The object of the study is to explore the content difference of activecompounds, paclitaxel,7-xylosyltaxol and cephelomannine in T. chinensis var. maireiliving in different areas of eastern China and its relationship with ecological factors.The active compounds contents in samples of the plant collected from differentconditions were analyzed by methods of ultrasonic extraction and HPLC. Differenceof the compounds contents was revealed by mean of statistical approach. Toinvestigate the relationship between the active compounds contents and ecologicalfactors such as soil, climate, slope aspect, slope position, soil properties of differentsampling areas were detected using analytical methods of soil physicochemicalproperties like Potassium dichromate capacity-external heating method, Nitricacid-perchloric acid-hydrofluoric acid digestion method and so on. Meanwhile,distributive changes of the active compounds contents in wild and cultivatedindividuals growing at the same areas were compared and difference of thecompounds contents in the plant harvested in different cultivated years as well asdifferent periods were analyzed. The results of the study have definite reference valuein high quality germplasm screening, artificial cultivation and breeding and wildresource conservation and development of T. chinensis var. mairei. The conclusions ofthe paper are as follows:1) Difference of contents of active compounds, paclitaxel,7-xylosyltaxol andcephelomannine in T. chinensis var. mairei of different populations was significant(P<0.05). The range of paclitaxel content was in0.0034%(Yifeng, Jiangxi) to0.0061%(Jianyang, Fujian; Fuliang, Jiangxi). The range of7-xylosyltaxol contentwas in0.0104%(Longquan, Zhejiang) to0.0373%(Wuyi, Zhejiang). The range ofcephalomannine content was in0.0059%(Yifeng, Jiangxi) to0.0133%(Mingxi,Fujian).2) The active compounds contents in T. chinensis var. mairei from differentregions were notably dependent on some soil properties. Paclitaxel content in the plant was significantly effected by available phosphorus content in surface soil of0-20cm (r=0.858，P=0.029). Cephalomannine content was closely related to totalnitrogen content in surface soil of0-20cm (r=-0.947，P=0.004) and the contents oftotal nitrogen (r=-0.920，P=0.009) and organic matter (r=-0.857，P=0.029) in deepsoil of20-40cm (P<0.05). Other soil properties, such as pH, electric conductivity,available potassium and so on, also had some influence on the secondary metabolitescontents in the plant (P>0.05). However, the correlation of the active compoundscontents in the individuals and climate factors, like annual average rainfall etc, didn’treach significant level (P>0.05).3) Paclitaxel and7-xylosyltaxol contents in the individuals growing in sunnyslopes were respectively1.5-2.3times and1.9-2.7times than those growing in shadyslopes, with significant difference of paclitaxel and7-xylosyltaxol contents (P<0.05).The difference of the active compounds contents in the plant of different slopepositions at the same area wasn’t significant (P>0.05), and the active componentscontents were comparatively high in rather low slope positions (P>0.05).4) The difference of paclitaxel contents in wild and cultivated individuals wassignificant (P<0.05), with high content in wild ones. No matter wild and cultivatedones, the three active compounds were the highest in barks among the tissue of barksand branches and leaves, and the difference of the content in different tissues wassignificant (P<0.05). The difference of paclitaxel and7-xylosyltaxol contents inbranches and leaves of the individuals of different tree canopies was significant(P<0.05, P<0.05) and the contents in upper tree canopies was relatively high.5) The difference of paclitaxel in the individuals of different cultivated years (3-7years) was significant (P<0.05), of which paclitaxel content was highest in4yearsindividual. Paclitaxel content in the samples collected in different periods (April andOctober) was comparatively high in individuals harvested in October than harvestedin April (P<0.05). Besides, the difference of the active compounds in the plantcollected from different cultivated areas was significant (P<0.05), which may becaused by the reason of ecological factors, like soil, climate etc, hereditary charactersof the plant and so on.