【作者】 王一丁；

【导师】 刘世贵；

【作者基本信息】 四川大学 ， 遗传学， 2002， 博士

【摘要】 实验表明有毒杂草紫茎泽兰的乙醇提取物具有较强的灭蚜生物活性。运用渗漉、萃取、薄层层析（TLC）、色-质联用（GC-MS）等技术，同时进行灭蚜毒力跟踪测定，我们首次从紫茎泽兰中分离得到了一种灭蚜活性物质——紫茎泽兰素A，其化学名为3β，5α—3—羟基—雄甾—16—内型[16，17—b]—1’—甲基吲哚，其分子式为C₂₆H₃₅NO，分子量为377。紫茎泽兰素A对棉蚜的毒力回归方程式为：y=4.33+1.19x，LC₅₀为362.8mg／L。棉蚜经2.00g／L紫茎泽兰素A处理，其24小时后的校正死亡率达81.3％，显示紫茎泽兰素A有很高的灭蚜活性，这对我们开发新型高效低毒杀虫剂具有很好的启示作用。 生物化学与毒理学实验表明紫茎泽兰素A对棉蚜乙酰胆碱酯酶活性和Na-K-ATP酶活性有明显的抑制作用，且抑制作用随着药液浓度的增加和中毒时间的延长而加深。棉蚜经2.00g/L紫茎泽兰素A溶液处理12小时后，其体内乙酰胆碱酯酶活性仅为对照组蚜虫体内乙酰胆碱酯酶活性的30.3％，其体内的Na-K-ATP酶活性仅为对照组棉蚜Na-K-ATP酶活性的21.60％。。紫茎泽兰素A对乙酰胆碱酯酶和Na-K-ATP酶的抑制作用是其导致蚜虫死亡的重要原因。较高浓度（2.00g/L）的紫茎泽兰素A亦对棉蚜α-乙酸萘酯羧酸酯酶表现 四f！I大学博士学位论文出抑制作用，表明紫茎泽兰素A不仅可以作为杀虫剂使用，而且还可以与其它杀虫物质混用并发挥增效作用。 安全性实验表明紫茎泽兰素A 对大鼠的急性经口LD50)5000mg／KIn，对大鼠的急性经皮 LD50＞2000mg／KIn，对家兔皮肤、眼粘膜无刺激性。紫茎泽兰素A属低毒类化合物，可望作为高效、低毒、安全、无公害农药在生产中应用。更多还原

【Abstract】 Major: Genetics Candidate for Ph. D. Wang Yiding Tutor Professor Liu ShiguiIn this paper, the toxicity of Eupatorium adenophorum (Spreng.) to the cotton aphid (Aphis gossypii Glover) was evaluated in laboratory. In a laboratory study the total ethanol extract from E. adenophorum is highly effective against the aphids. The LC50 of the total ethanol extract against apterous adult aphids is 167. 9mg/L, 48 hours after treatment by dipping method. Hexane extract, chloroform extract, ethyl acetate extract and ethanol extract were got from the total ethanol extract in proper order. The corrected mortality of aphids treated with the chloroform extract of different concentrations is higher than that of aphids treated with other 3 kinds of extracts at same concentrations. It is thought that E. adenophorum contains a few kinds of aphid-killing substances. By means of the techniques of systematic extraction, thin layer chromatography and GC-MS,an active aphid-killing substance named Eupatorin A was separated out of the chloroform extract and purified at the first time. Its chemical name is 1’H-Androst-16-eno[16, 17-b] indol-3-ol, 1-methyl-, (3. beta., 5. alpha.), its chemical formular is C26H35NO. Its molecular weight is 377. Eupatorin A at a concentration of 2g/L can kill 81. 3% of the cotton aphids. Its LC50 against cotton aphids is 362. 8mg/L. Tests also showed that Eupatorin A can inhibit the activity of AchE and Na-K-ATPase of the cotton aphids in vitro and in vivo. The inhibition was deepened with the bigger concentration of Eupatorin A and the longer toxic time. 48 hours after the aphids were treated with Eupatorin A at a concentration of 2g/L, the activity of AchE and Na-K-ATPase of the cotton aphids was only 30.3% and 21.6% of that of the contrast respectively. These could be the deaths of cotton aphids. When at a concentration of 2g/L, Eupatorin A can inhibit the activity of carboxylesterase of the aphids. This showed that Eupatorin A can not only kill the aphids but also be used as a synergist to achieve better pest-killing effectiveness. The security experiments have showed Eupatorin A is less toxic and safe for environment organism.更多还原