以水、乙醇、正丁醇、乙酸乙酯、氯仿和石油醚为溶剂,采用冷浸法对小桐子(Jatropha curcas L.)枝叶进行了粗提并采用喷雾法测定了各粗提物对豌豆长管蚜〔Acyrthosiphon pisum (Harris)〕和桃蚜〔Myzus persicae (Sulzer)〕的毒力,从中筛选出毒力最高的粗提物进行进一步的活性组分分离及毒杀活性测定。 结果显示,随溶剂极性的减小,小桐子枝叶不同溶剂粗提物的提取率降低,其中水和乙醇粗提物的提取率较高,分别为 18. 76% 和 11. 94% ;6 种溶剂粗提物对豌豆长管蚜和桃蚜都具有一定的毒力,其中,乙醇粗提物的毒力显著高于其他溶剂粗提物,LC50 分别为 2. 693 3 和2. 565 6 g· L ^{- 1} 。 乙醇粗提物的水、正丁醇、乙酸乙酯、氯仿和石油醚萃取物均对桃蚜有一定的毒杀活性,其中石油醚萃取物的萃取率最高(74. 27% ),对桃蚜的毒杀活性均显著高于其他溶剂萃取物,8 g· L ^{- 1} 石油醚萃取物对桃蚜的 24 h 校正死亡率高达 94. 5% 。 研究结果表明,小桐子枝叶的灭蚜活性组分存在于其乙醇粗提物的低极性组分中。 根据实验结果初步确定了小桐子枝叶灭蚜活性组分的提取流程。

 

Crude extracts from branches and leaves of Jatropha curcas L. were obtained with water,ethanol, butanol, ethyl acetate, chloroform. and petroleum ether by cold extracting method, and toxicity of each crude extract against Acyrthosiphon pisum (Harris) and Myzus persicae ( Sulzer) was studied by spray method. Active component separation and toxicity assay in the crude extracts with the highest toxicity were conducted. The results show that the extraction rate falls as the polarity of solvents decreases, and the extraction rates of water (18. 76% ) and ethanol (11. 94% ) are higher. All of the six crude extracts have a certain toxicity against A. pisum and M. persicae, in which the toxicity of ethanol crude extract is obviously higher than that of the others, with LC50 of 2. 693 3 and 2. 565 6 g· L ^{- 1}, respectively. All the water, butanol, ethyl acetate, chloroform. and petroleum ether partitioned extracts from ethanol crude extract have a certain toxicity against M. persicae. The partitioned rate of petroleum ether partitioned extract is the highest (74. 27% ) and its toxicity against M. persicae is obviously higher than that of the others. The corrected mortality of M. persicae after 24 h exposure to petroleum ether partitioned extract (8 g· L ^{- 1}) is up to 94. 5% . It is concluded that active aphid-killing components in branches and leaves of J. curcas exist in low polarity fractions of ethanol crude extract. A preliminary extraction procedure of active aphid-killing components is determined according to this study.