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超临界CO2萃取印楝种子中印楝素的研究 总被引:5,自引:2,他引:5
《精细化工》2003,20(9):513-514
应用超临界CO2萃取技术从印楝种子中萃取印楝素,研究了萃取温度、压力和夹带剂对印楝素萃取效果的影响.当萃取温度为35
℃、压力为15 MPa、甲醇用量为CO2体积的3%时,可将印楝种子中90%以上的印楝素A萃取出来,所得产品印楝素A的质量分数为20.3%. 相似文献
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[目的]筛选出对瓜实蝇老熟幼虫和蛹具有较好毒杀作用的药剂,为瓜实蝇的化学防治提供依据。[方法]采用浸虫法分别测定14种杀虫剂对瓜实蝇老熟幼虫和蛹的毒杀作用。[结果]印楝素、苦参碱、阿维菌素、甲氨基阿维菌素苯甲酸盐对瓜实蝇老熟幼虫和蛹具有较高毒力,对老熟幼虫的LC50值分别为0.0092、0.1961、1.8803、3.2526 mg/L;对蛹的LC50值分别为0.0058、40.598、129.357、122.173 mg/L。[结论]印楝素、苦参碱、阿维菌素、甲氨基阿维菌素苯甲酸盐可作为瓜实蝇的防治药剂。 相似文献
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目的:研究三桠苦提取物的抑菌活性。方法:以95%乙醇为溶剂,分别利用超声波提取和回流提取方法获得三桠苦提取物,利用滤纸片扩散法,分析两种提取方法的提取物对大肠杆菌、金黄色葡萄球菌、枯草杆菌和沙门氏菌的抑菌活性差异,确定抑菌活性较好的提取方法。利用该方法提取三桠苦得到提取物,采用溶剂萃取法,依次用石油醚、二氯甲烷、乙酸乙酯和正丁醇分别萃取三桠苦提取物,得到极性大小不同的萃取物,再次利用滤纸片扩散法,比较这些萃取物对四种菌的抑菌活性,确定三桠苦的抑菌活性部位,为三桠苦抑菌活性成分的深入研究提供参考。结果:回流提取法获得的样品抑菌活性优于超声提取法;石油醚、二氯甲烷萃取物表现出较好的抑菌活性,乙酸乙酯萃取物抑菌活性较差、正丁醇萃取物无抑菌活性。结论:三桠苦提取物具有抑菌活性,其二氯甲烷萃取物是具有较强抑菌作用的活性部位。 相似文献
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22种中草药提取物杀根结线虫活性 总被引:4,自引:1,他引:4
通过对南方根结线虫2龄幼虫的直接触杀试验,研究了22种中草药在采用不同提取溶剂和不同提取手段条件下所得提取物的杀根结线虫活性.结果表明:胡黄连、狗脊、木香、蛇床子、石榴皮、瞿麦、吴茱萸、甘草、花椒和艾蒿10种中草药提取物具有较强的杀根结线虫活性,并且胡黄连、木香、蛇床子和石楠在多种提取方式下均能提取出较强的杀线虫活性成分,其中胡黄连和狗脊的水煮提取物经过石油醚、乙酸乙酯和正丁醇依次萃取后,所得活性萃取物对南方根结线虫2龄幼虫72 h内的LC50值分别为81.44、67.37 mg/L. 相似文献
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通过气相色谱-质谱联用仪对苦苣菜、葡萄籽的CO_2超临界萃取物进行成分分析,得到主要成分为脂肪酸类,对其脂肪酸建立定性定量方法,以准确分析其萃取物的脂肪酸含量。运用优化的CO_2超临界萃取方法得到苦苣菜、葡萄籽提取物,通过气质联用仪及NIST谱库对提取物进行成分分析,改进气相色谱条件(色谱柱为HP-5msUI,分析时间为57min),优化质谱条件(单反应监测模式和分段扫描),得到多种脂肪酸的定性定量方法。通过气质联用仪解析了苦苣菜CO_2超临界提取物的活性成分,脂肪酸测定方法对于植物提取物具有较好的线性关系(相关系数R均高于0.992 0)、回收率在80%~105%之间,定量限在0.002~0.010 g/kg之间,RSD均小于4.0%。测得苦苣菜萃取物中有20种脂肪酸,不饱和脂肪酸占总脂肪酸的83.5%,葡萄籽萃取物中检出了10种脂肪酸,不饱和脂肪酸占总脂肪酸的91.74%。脂肪酸测定方法操作简便、灵敏度高,缩短了检验时间,适用于植物萃取物中脂肪酸的测定。解析了苦苣菜的活性成分,得到了苦苣菜、葡萄籽中脂肪酸的准确含量。 相似文献
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多溶剂萃取法精制印楝素的研究 总被引:4,自引:1,他引:3
对比研究了多溶剂萃取法与单溶剂萃取法精制印楝素的效果,并通过正交试验法选择了多溶剂萃取法精制印楝素的最佳试验条件为:萃取溶剂V(二氯甲烷):V(乙酸乙酯)1:5,分相液V(丙酮):V(水)1:1,V(萃取溶剂):V(分相液)10:3,该方法可将乙醇提取物中印楝素的质量分数从 3.68% 提高到 17.76%。多溶剂萃取法是一种简单高效的精制印楝素的方法。 相似文献
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An aqueous suspension and an ethanolic extract of neem seed kernel (NSK) at 0.3, 0.6, 1.2, 2.5, and 5.0% concentrations were tested for ovipositional deterrency, feeding deterrency, toxicity, sterility, and insect growth regulatory effects on a larval parasitoid, Bracon hebetor. Neither NSK extracts delivered in the food or by contact influenced the B. hebetor oviposition (parasitization). They also did not cause parasitoid sterility through feeding, but they showed feeding deterrent effects for a limited period. Parasitoid eggs and pupae also were unaffected by the extracts tested. The parasitoid larvae, however, were killed by feeding contaminated host larvae and also through contact with neem extracts. Thus, a minimum safety period is suggested for inundative releases of B. hebetor in integrated pest management. 相似文献
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The neem tree, Azadirachta indica, produces a plethora of triterpenoids. One of these is azadirachtin, a complex compound with powerful insecticidal properties. The biosynthesis of azadirachtin starts with a steroid precursor and proceeds via two levels of structural complexity, i.e., furan ring formation and C-ring opening, after which further modifications yield azadirachtin, Antifeedant and toxic properties of azadirachtin against insects were compared with those of various compounds from the two lower levels of structural complexity. To larvae of the moth Spodoptera littoralis, several compounds from the lower structural levels showed strong antifeedant activity, comparable to that of azadirachtin. Nymphs of the locust Schistocerca gregaria in antifeedancy tests were more sensitive to azadirachtin than to the other compounds tested. To Spodoptera littoralis, Schistocerca gregaria, and the bug Oncopeltus fasciatus, azadirachtin was very toxic, exerting severe growth and molt disrupting effects. In contrast, compounds from the lower structural levels than azadirachtin showed virtually no toxicity to these three insects. Thus, although several simpler triterpenoid structures other than azadirachtin have insect antifeedant activity, the combination of strong antifeedant and toxic properties of azadirachtin may provide the more important chemical protection of the neem tree. Our data reveal no explicit link between antifeedant activity and toxicity of individual neem triterpenoids. 相似文献
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使用超临界CO2萃取法和水蒸汽减压蒸馏萃取柑桔皮精油,两种方法精油收率相当,最高收率均为1.2%。但水蒸汽减压蒸馏法提取的精油质量好,为浅黄色流动性液体,气味具有新鲜柑桔皮的清香,流程简单,超临界CO2萃取所得产品质量差,流动性差,为深黄色半流动性液体,杂质较多。 相似文献
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石菖蒲根茎提取物对粘虫的生物活性 总被引:19,自引:0,他引:19
用石菖蒲的甲醇、石油醚、水等6种不同极性溶剂的提取物对粘虫进行了室内生物活性测定。结果表明:石菖蒲的甲醇提取物对粘虫具有极强的拒食和生长发育抑制作用,兼具一定触杀活性。在非选择性条件下,石菖蒲甲醇提取物对粘虫4龄幼虫拒食率高达91.89%,拒食活性显著高于其它提取物;在毒杀和生长发育抑制试验中,取食含毒叶片后的4龄幼虫体重在3d内出现负增长,4d后试虫全部死亡;此外,石菖蒲甲醇提取物对粘虫幼虫也有一定触杀活性,其死亡率超过60%。在该试验中,石油醚提取物对粘虫幼虫的拒食活性仅次于甲醇提取物,而对粘虫的生长抑制作用则低于甲醇、氯仿及乙酸乙酯3种溶剂的提取物。6种不同极性溶剂提取物中,以水提取物对粘虫的生物活性最小。 相似文献
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Hexane and ethanol extracts of seeds from 22 species of plants of the family Meliaceae from a number of countries were prepared. The extracts were submitted to antifeedant and toxicity bioassays utilizing fall armyworm [Spodoptera frugiperda (J.E. Smith)] (Lepidoptera: Noctuidae) larvae and striped cucumber beetle [Acalymma vittatum (F.)] (Coleoptera: Chrysomelidae) adults. Toxicity tests were also performed with brine shrimp,Anemia salina Leach. Feeding inhibition and mortality produced by some of these extracts were comparable to and, in certain cases, slightly greater than the effects produced by comparable neem (Azadiracta indica A. Juss.) seed preparations. Brine shrimp toxicity data do not extrapolate to insect activity, and vice versa.Presented at the national meeting of the Entomological Society of America in Hollywood, Florida, December 8–12, 1985.Mention of firm or product names does not imply recommendation or endorsement by USDA over others not mentioned. 相似文献