【作者】 姜萍；

【导师】 安鑫南；

【作者基本信息】 南京林业大学 ， 林产化学加工工程， 2006， 博士

【摘要】 本文以苦楝树皮为原料进行了有效成分苦楝素的提取分离方法及其生物活性的研究。探讨了有机溶剂提取、超临界CO₂流体萃取、微波辅助提取及超声波提取的各种影响因素，并筛选出较佳的工艺条件。进行了苦楝提取物及其活性成分对大叶黄杨尺蠖的杀虫活性的研究；同时也进行了不同溶剂的苦楝提取物对两种真菌（黑曲霉、绿色木霉）的抑菌实验；并采用多种分离手段对苦楝树皮有效成分的分离与纯化进行了研究。主要研究结果如下： 首次系统地对比研究了从苦楝树皮中提取苦楝素的4种方法，通过实验，得出了不同提取方法的最佳条件。超临界CO₂萃取在萃取温度45℃、压力20MPa、夹带剂60％乙醇的情况下萃取2h，苦楝素的萃取率为0.850％；微波辅助提取法，以60％乙醇为溶剂，料液比为1：9（g：mL，下同），微波功率340W，辐射时间40S，苦楝素的提取率为0.693％；超声波提取法，以60％乙醇为溶剂，料液比为1：9，超声波作用时间为30min，超声波功率为200W，苦楝素的提取率为0.715％。将上述3种提取方法与传统的有机溶剂提取法进行详细的比较，结果表明：对于苦楝素提取，超声波提取法最好。 首次对林业害虫大叶黄杨尺蠖进行了杀虫活性的研究，实验结果表明：苦楝树皮提取物对大叶黄杨尺蠖具有一定的拒食和胃毒作用，苦楝树皮中甲醇提取液和氯仿提取液对大叶黄杨尺蠖幼虫具有强烈的拒食和毒杀作用，当浓度为400ppm时对4龄幼虫24h的拒食率大于80％，处理后72h校正死亡率在93％以上。测定结果表明，苦楝杀虫活性成分主要集中在氯仿萃取物中。氯仿萃取物对大叶黄杨尺蠖的拒食和毒杀作用与苦楝素化合物相比较活性很相近，在实际应用中可直接采用氯仿萃取物作为杀虫试剂。 用苦楝树皮和苦楝果实的不同溶剂和不同浓度的提取物对两种真菌（黑曲霉、绿色木霉）进行了抑菌活性试验，结果发现不同溶剂和不同浓度的提取液对供试菌的抑菌活性效果不同。苦楝树皮提取液对供试菌的抑制效果整体看比苦楝果实好；苦楝树皮乙醇提取液抑菌活性最强，对绿色木霉和黑曲霉都有很好的抑菌活性。最低抑菌浓度的试验表明：苦楝树皮乙醇提取液对绿色木霉和黑曲霉的最低抑菌浓度均为0.5％，甲醇提取物对黑曲霉和绿色木霉的最低抑菌浓度为2％。 苦楝树皮中苦楝素分析与检测结果表明：苦楝素的分子式为C₃₀H₃₈O₁₁熔点为244～245℃，苦楝素纸层析测定苦楝素的比移值R_f值为0.77（展开剂：异丙醇-甲酰胺-水15：5：80，26～28℃）。比旋光度[α]_D¹⁶-6.25（乙醇溶液），紫外UVλmax（无水乙醇）为213nm，红外光谱图在3486cm^-1、2925cm^-1、1735cm^-1、1637cm^-1、1243cm^-1、1065cm^-1、880cm^-1有主要特征峰。苦楝素通过液-质联用分析仪测得苦楝素的分子量为574.6。通过质谱分析仪的计算机检索以及结构分析得出苦楝素的分子结构。 以上研究结果为综合利用我国苦楝树资源开辟了一条新的途径。更多还原

【Abstract】 The extraction and separation of effective component from the bark of Melia azedarach L.and its bioactivity have been studied in this dissertation. The effecting factors of different extraction methods, including supercritical carbon dioxide extraction, ultrasonic extraction, microwave assistant extraction and traditional solvent extraction, and the optimum extraction conditions were investigated. Study on antifeeding and toxic effects of extractives and effective component from the bark of Melia azedarach L. against forest pest Abraxas mirandu Butler as well as the study on extractives obtained from extraction with different solvents from Melia azedarach bark and fruit against fungi have been carried out. The main results were as follows:Extraction methods of toosendanin from the bark of Melia azedarach L. were systematically investigated in this dissertation, and several extraction methods, including supercritical carbon dioxide extraction, ultrasonic extraction, microwave assistant extraction and traditional solvent extraction, were compared in detail. The results indicated that the ultrasonic extraction method was preferred among the discussed methods. In the case of ultrasonic extraction, the optimum conditions were as the follows: 60% ethanol as solvent, the ratio of feedstock to liquor 1:9, extraction time 30 min, temperature 40°C, and ultrasonic power 200W. Under the optimum conditions, the yield of toosendanin was 0.715 %.Antifeeding and toxic effects of extractives from the bark of Melia azedarach L. against forest pest Abraxas mirandu Butler were investigated . Methanol and chloroform extractives from the bark have stronger antifeeding and higher toxic effect. For fourth instar larvae of Abraxas mirandu Butler, the antifeeding rate was 80% after 24 h of treatment and adjusted mortality rate was 93% after 72h of treatment at concentration of 400 ppm. The results revealed that chloroform extractive mostly,contain pesticide activity component, antifeeding and toxic effect of chloroform extractive was almost the same as that of toosendanin component. Chloroform extractive was directly used for botanical pesticide in practical application.Investigation on bacteriostatic activity of extractives from Melia更多还原