大血藤叶片提取物抑菌活性与次生代谢产物含量的通径分析

Path Analysis of Anti-bacterial Activity and Secondary Metabolite Contents of Sargentodoxa cuneata Leaves

目的比较5个不同产地大血藤叶片提取物对5种细菌的抑菌活性,通过对抑菌活性和次生代谢产物含量进行通径分析,以确定进一步开发研究的目标化合物。方法采用纸片琼脂扩散法测定抑菌圈大小,利用分光光度法对次生代谢产物含量进行测定,采用逐步回归和通径分析的方法确定目标化合物。结果大血藤叶片提取物的抑菌活性高于其他器官。不同产地大血藤叶片提取物对5种细菌的抑菌活性与浓度之间存在明显的剂量-效应关系,即随着浓度的升高,抑菌效果明显增高。当药液为每1 mL含1 g生药,大血藤叶片提取物对5种细菌的抑菌效果为枯草芽孢杆菌>金黄色葡萄球菌>大肠杆菌> 苏云金芽孢杆菌>铜绿假单胞菌。不同产地大血藤叶片的抑菌活性与次生代谢产物含量差异均较大,抑菌活性与次生代谢产物含量之间的通径分析显示,影响犬血藤叶片提取物抑菌活性的主要次生代谢产物为黄酮类化合物和生物碱。聚类分析显示高抑菌活性的大血藤的适生区域为大雷山和百山祖。结论大血藤叶片具有抑菌活性。

OBJECTIVE To ascertain the goal compound for further research, to compare the anti-bacterial activity of the leave extracts of Sargentodoxa cuneata from different regions on five bacteria strain and to apply the path analysis of the anti-bacterial activity and the secondary metabolite contents of S. cuneata leaves. METHODS Kirby-Bauer disk agar diffusion method was used and the diameter of anti-bacterial circle was calculated. The contents of secondary metabolites were determined by spectrometry. The stepwise regression and path analysis were used to aseertain the goal compound. RESULTS The anti-bacterial activity of S. cuneata leaves extracts was higher than other organs. There was the dose-effect relationship between the anti-bacterial activity and the content of S. cuneata leaves extracts from five different producing areas, i.e. the anti-bacterial activity increased along with the increasing of the content of the extracts. When the content of the extracts was 1 g· mL^-1, the rank of anti-bacterial activity was arranged from high tolow as follows： Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Bacillus thuringiensis and Pseudomonus acruginosa. The anti-bacterial activity and the secondary metabolites content of S. cuneata leaves in live different geographical sources were significantly different. The path analysis showed that the major factors which influenced the anti-bacterial activity of S. cuneata leaves extracts were flavnoids and alkaloids. The cluster showed that the Daleishan Mountain in Tiantai County and Baishanzu Mountain in Qinyuan County were suitable for the growth of S. cuneata. CONCLUSION Obviously anti-bacterial effect is observed in the leaves of S. cuneata, and the further goal compound might be the flavanoids and alkaloids.