目的对马比木Nothapotyes pittosporoides中的喜树碱进行组织学定位, 并测定不同产地、不同生长季节和不同部位的马比木中喜树碱的量。方法采用荧光显微技术进行喜树碱的定位, 高效液相色谱法进行测定。Hypersil ODS₂色谱柱(250 mm×4.6 mm, 5μm), 以乙腈-水(6:4)为流动相梯度洗脱, 体积流量1.0 mL/min, 柱温20℃, 检测波长254 nm。结果马比木中喜树碱主要积累于根部和茎部的韧皮部的分泌细胞内;喜树碱的量具有季节性变化规律, 夏季低, 春秋高;细根中喜树碱的量最高, 主根次之, 主茎、幼茎及叶的量依次递减。结论马比木喜树碱主要贮藏于根部树皮内, 不同产地、不同季节、不同部位的马比木植物中的喜树碱量差异较大。

Objective To conduct histological localization of camptothecin in Nothapodytes pittosporoides and determine the contents of camptothecin in different parts of the plant from different regions in different seasons.Methods Histological localization of camptothecin was carried out by fluorescence microscopy.HPLC method was used to determine the contents.A Hypersil ODS2 column(250 mm×4.6 mm,5 μm) was used as analytical column.The mobile phase consisted of acetonitrile-water(6:4).The flow rate was 1.0 mL/min and the column temperature was 20 ℃.Detection wavelength was at 254 nm.Results The camptothecin was mainly accumulated in secretory cells in the phloem of roots and stems.The contents of camptothecin were seasonally changed with a low content in summer and higher contents in spring and autumn.There was the highest content of camptothecin in the fine roots,the secondary content in the main roots,and the contents in stems,young twigs,and leaves were decreased gradually.Conclusion The camptothecin accumulates mainly in the root bark,and the contents of camptothecin among different parts of N.pittosporoides from different regions in different seasons are greatly different.

湖南省自然科学基金资助项目(09JJ3051);湖南省生态学重点建设学科开放基金项目(JSS2009Z03)