千里光抗菌有效部位化学成分及其急性毒性研究

用60％乙醇作溶剂制备千里先抗菌有效部位冻干粉（即千里光60％乙醇提取物）．分析其化学成分．并用改良寇氏法测定其对小鼠腹腔注射的急性半数致死量（LD50）。结果发现，千里光60％乙醇提取物合有生物碱、黄酮类化合物，但不含双稠吡咯啶生物碱；测得千里光60％乙醇提取物对小鼠腹腔注射的LD50为2206mg／kg，95％可信限为1867—2607mg／kg。表明千里光60％乙醇提取物属低毒性物质，并可保留千里光的有效成分生物碱和黄酮类化合物而排除其中的双稠吡略啶生物碱．进一步提高了千里光的安全性。

Analysis on the chemical compositions of antibacterial extract from Senecio scandens Buch. -Ham. And tests on its acute toxicity

The freeze-dried powder of antibacterial extract from Senecio scandens Buch.-Ham.was prepared using 60% alcohol as the solvent.The main chemical compositions of the extract was analyed,and the aeute medium lethal dose（LD50） intraperitoncally injected to mice of the extract was conducted with the modified Kaber＇s method.The results showed that the extract contained alkaloids and flavones but not pyrrolizatine alkaloids （PAs）,and that the LD50 of the extract intraperitoncally injected to mice was 2206mg/kg,with the 95% confldence limit of 1867-2607mg/kg.It was indicated that the extract was in lower toxicity and contained effective parts of alkaloids and flavones but got rid of PAs from S.scandens,which enhanced the herh＇s safety.