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Johnny A. Hembree Ciung-Jer Chang Jerry L. McLaughlin John M. Cassady Daniel J. Watts Ernest Wenkert Sebastiko Ferreira Fonseca Jayr De Paiva Campello 《Phytochemistry》1979,18(10):1691-1694
The cytotoxic norditerpene dilactones nagilactone F and its new congener nagilactone G have been isolated from the bark constituents of Podocarpus milanjianus and Podocarpus sellowii. The diterpenes totarol, 19-oxototarol and macrophyllic acid were also isolated. 相似文献
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The insecticidal activity of asperentin, a dihydroisocoumarin secondary metabolic product of an entomogenous strain of Aspergillus flavus, and some derivatives and analogues, is compared with that of fusarentin dimethyl ether, from Fusarium larvarum, and ochratoxin A in two bioassays against Calliphora erythrocephala and Aedes aegypti. 相似文献
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Joe W. Dorner Richard J. Cole James P. Springer Richard H. Cox Horace Cutler Donald T. Wicklow 《Phytochemistry》1980,19(6):1157-1161
Two new biologically-active norditerpenoid dilactones were purified from culture extracts of Aspergillus wentii and assigned the trivial names wentilactone A and wentilactone B. The absolute chemical structure of wentilactone A was determined by single crystal X-ray diffraction and circular dichroism. The structure of wentilactone B was determined by 1H and 13C NMR analyses. Wentilactone A had an ld50 of 7.0 mg/kg when administered orally to 1-day-old chickens. Both metabolites inhibited growth in wheat coleoptile bioassays. 相似文献
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杠柳毒素NW的杀虫活性 总被引:4,自引:0,他引:4
杠柳毒素NW是从杠柳(Periploca sepium Bunge)中分离的新化合物,是其主要的杀虫成分。对杠柳毒素NW的杀虫活性进行了测定,结果表明:杠柳毒素NW对小地老虎无明显的胃毒活性,对3龄的小菜蛾、粘虫和菜粉蝶幼虫均有较强的胃毒活性,处理后24h的致死中浓(LC50)分别是866.17,927.92和1107.08mg·L-1;对上述供试昆虫均无明显的触杀活性。此外,杠柳毒素NW对棉蚜、棉红蜘蛛及卫生害虫家蝇3龄幼虫和淡色库蚊3龄幼虫均有很好的毒杀活性,处理后24h的LC50分别为1743.17,2179.49,714.94和653.29mg·L-1。 相似文献
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Identifying insecticide resistance mechanisms is paramount for pest insect control, as the understandings that underpin insect control strategies must provide ways of detecting and managing resistance. Insecticide resistance studies rely heavily on detailed biochemical and genetic analyses. Although there have been many successes, there are also many examples of resistance that still challenge us. As a precursor to rational pest insect control, the biology of the insect, within the contexts of insecticide modes of action and insecticide metabolism, must be well understood. It makes sense to initiate this research in the best model insect system, Drosophila melanogaster, and translate these findings and methodologies to other insects. Here we explore the usefulness of the D. melanogaster model in studying metabolic-based insecticide resistances, target-site mediated resistances and identifying novel insecticide targets, whilst highlighting the importance of having a more complete understanding of insect biology for insecticide studies. 相似文献
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Fitches E Wiles D Douglas AE Hinchliffe G Audsley N Gatehouse JA 《Insect biochemistry and molecular biology》2008,38(10):905-915
The heterodimeric and homodimeric garlic lectins ASAI and ASAII were produced as recombinant proteins in the yeast Pichia pastoris. The proteins were purified as functional dimeric lectins, but underwent post-translational proteolysis. Recombinant ASAII was a single homogenous polypeptide which had undergone C-terminal processing similar to that occurring in planta. The recombinant ASAI was glycosylated and subject to variable and heterogenous proteolysis. Both lectins showed insecticidal effects when fed to pea aphids (Acyrthosiphon pisum) in artificial diet, ASAII being more toxic than ASAI at the same concentration. Acute toxicity (mortality at =48h exposure; similar timescale to starvation) was only apparent at the highest lectin concentrations tested (2.0mgml(-)1), but dose-dependent chronic toxicity (mortality at >3d exposure) was observed over the concentration range 0.125-2.0mgml(-1). The recombinant lectins caused mortality in both symbiotic and antibiotic-treated aphids, showing that toxicity is not dependent on the presence of the bacterial symbiont (Buchnera aphidicola), or on interaction with symbiont proteins, such as the previously identified lectin "receptor" symbionin. A pull-down assay coupled with peptide mass fingerprinting identified two abundant membrane-associated aphid gut proteins, alanyl aminopeptidase N and sucrase, as "receptors" for lectin binding. 相似文献
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The insecticidal activity of a complex mixture of enniatins, cyclohexadepsipeptides produced by Fusarium lateritium, a pathogen of the scale insect Hemiberlesia rapax, is compared with that of enniatin A and beauvericin in two bioassays against Calliphora erythrocephala and Aedes aegypti. 相似文献
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Pritam Singh Peter G. Fenemore John S. Dugdale Graeme B. Russell 《Biochemical Systematics and Ecology》1978,6(2):103-106
When incorporated into artificial diets, the milled foliages of many New Zealand conifers are toxic to larvae of housefly (Musca domestica), codling moth (Laspeyresia pomonella) and light-brown apple moth (Epiphyas postvittana). The most toxic foliages are those of Podocarpus nivalis which contains diterpene lactones, and Dacrydium laxifolium, which has a high concentration (1%) of phytoecdysones. The insecticidal activities of the plants are discussed in relation to their insect associations, chemistry and taxonomy. 相似文献
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嗜线虫致病杆菌HB310菌株杀虫蛋白的纯化及活性鉴定 总被引:8,自引:0,他引:8
嗜线虫致病杆菌Xenorhabdus nematophila HB310是从河北省土壤中筛选出的一株昆虫病原线虫体内分离纯化获得的共生菌,该菌的发酵液对多种昆虫有较高的杀虫活性。利用85%饱和度的硫酸铵盐析分别获得胞内蛋白提取物和上清液中胞外蛋白提取物,生测结果表明这两种蛋白提取物中都含有胃毒素和血腔毒素。通过制备型非变性凝胶电泳对蛋白提取物进行分离和纯化,得到了3种有杀虫活性的毒素蛋白(毒素Ⅰ、毒素Ⅱ和毒素Ⅲ),胞内的毒素蛋白与分泌到胞外上清液中的毒素蛋白是同种蛋白。毒素Ⅰ和毒素Ⅱ对棉铃虫初孵幼虫有明显的胃毒活性,但没有血腔毒性;毒素Ⅲ对大蜡螟幼虫有很强的血腔毒性,LD50为0.18 μg/头。SDS-PAGE图谱显示毒素Ⅰ和毒素Ⅱ是由多个多肽组成的复合蛋白,而毒素Ⅲ只分离出一条多肽。毒素Ⅱ在50℃处理10 min,其杀虫活性没有显著变化;70℃处理10 min对毒素Ⅲ杀虫活性没有显著影响。 相似文献
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Triguéros V Wang M Père D Paquereau L Chavant L Fournier D 《Archives of insect biochemistry and physiology》2000,45(4):175-179
Lectins from plants present an insecticidal activity most probably through their carbohydrate binding properties; as a consequence, their toxicity should vary with the presence of a competitive sugar in the ingested food. In order to test this hypothesis, we performed competition experiments between insecticidal activity and carbohydrate binding. For this purpose, we used a lectin from Lathyrus ochrus and the specific carbohydrate for this protein, glucose. In toxicological tests with Drosophila melanogaster, we observed a decrease of lectin toxicity when glucose was added to the larva-rearing medium. This result suggests that the toxicity of the lectin is correlated to its ability to bind sugar in the insect digestive tract and stresses the importance of sugar composition of the nutriment used for toxicological testing of lectins or in genetically modified plants. 相似文献
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《Bioorganic & medicinal chemistry》2016,24(3):391-402
A series of new pymetrozine analogues containing both methyl on the imine carbon and phenoxy group at the pyridine ring were designed and synthesized. Their insecticidal activities against bean aphid (Aphis craccivora), mosquito larvae (Culex pipiens pallens), cotton bollworm (Helicoverpa armigera), corn borer (Ostrinia nubilalis) and oriental armyworm (Mythimna separata) were evaluated. The results of bioassays indicated that most of the target compounds showed good insecticidal activity against bean aphid; especially, IIIf (80%) and IIIl (80%) exhibited higher aphicidal activity than pymetrozine (30%) at 5 mg/kg, and the two compounds still showed 20% and 30% mortality at 2.5 mg/kg, respectively, whereas pymetrozine displayed no activity at the same concentration. These compounds exhibited a completely different structure–activity relationship to that of known pymetrozine derivatives, in which it is thought introducing alkyl group on the imine carbon could be detrimental to the activities. Our new result suggested that the methyl on the imine carbon and phenoxy group at the pyridine ring of phenoxy group may play additive effects on the improvement of aphicidal activity. Besides this, compound IIIs, containing an allyl at the para position of phenoxy group, exhibited excellent insecticidal activity against mosquito larvae, lepidoptera pests cotton bollworm, corn borer and oriental armyworm. 相似文献
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Varitimidis C Petrakis PV Vagias C Roussis V 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(7-8):521-526
The insecticidal properties of the crude extracts of the leaves and flowers of Anemone pavonina were evaluated on Pheidole pallidula ants and showed significant levels of activity. Bioassay-guided fractionations led to the isolation of the butenolide ranunculin (1) as the active principle. Chemical investigations of the extracts showed them to contain as major components the sitosterol glycopyranoside lipids 2-5 and the glycerides 6-8. The structures of the metabolites were elucidated, following acetylation and hydrolysis of the natural products, by interpretation of their NMR and mass spectral data. The uncommon lipid metabolites 2-8 were isolated for the first time from the genus Anemone and this is the first report of insecticidal activity of the Anemone metabolite ranunculin against ants. 相似文献
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Alejandra Bravo Isabel Gómez Helena Porta Blanca Ines García‐Gómez Claudia Rodriguez‐Almazan Liliana Pardo Mario Soberón 《Microbial biotechnology》2013,6(1):17-26
Insecticidal Cry proteins produced by Bacillus thuringiensis are use worldwide in transgenic crops for efficient pest control. Among the family of Cry toxins, the three domain Cry family is the better characterized regarding their natural evolution leading to a large number of Cry proteins with similar structure, mode of action but different insect specificity. Also, this group is the better characterized regarding the study of their mode of action and the molecular basis of insect specificity. In this review we discuss how Cry toxins have evolved insect specificity in nature and analyse several cases of improvement of Cry toxin action by genetic engineering, some of these examples are currently used in transgenic crops. We believe that the success in the improvement of insecticidal activity by genetic evolution of Cry toxins will depend on the knowledge of the rate‐limiting steps of Cry toxicity in different insect pests, the mapping of the specificity binding regions in the Cry toxins, as well as the improvement of mutagenesis strategies and selection procedures. 相似文献
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P P Lyarskii V P Dremova L I Brikman V M Tsetlin 《Journal of hygiene, epidemiology, microbiology, and immunology》1985,29(1):69-76
On the basis of experimental data, the authors present a group of parameters for the purpose of unification of comparative evaluation of the insecticidal effect of preparations in aerosol containers designed for combatting flying and non-flying domestic insects. The advisability of evaluation of the effect of the preparations for combatting flying insects according to the concentration of insecticides ensuring death of flies in the course of 15 min and the corresponding expenditure of the mixture has been substantiated. Preparations designed for combatting non-flying insects should be evaluated according to the coefficients of acute action, ovicidal and residual effects. To facilitate analysis and evaluation of the preparations in aerosol containers, the authors propose their classification according to the parameters of the insecticidal effect. Classification of the preparations under study according to their parameters is presented. It has been demonstrated that compositions containing pyrethroids and their mixtures with DDVP--Neofos, Neofos-2 and Pif-Paf are the most efficient. 相似文献
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Tsoukatou M Tsitsimpikou C Vagias C Roussis V 《Zeitschrift für Naturforschung. C, Journal of biosciences》2001,56(3-4):211-215
The chemical composition of the volatile metabolites of Crithmum maritimum harvested from several geographic localities along the Mediterranean coasts was studied by GC and GC-MSD. The major oil constituents were found to be dillapiole, gamma-terpinene, sabinene, limonene and beta-phellandrene. The Western populations were richer in dillapiole, whereas the Southern collections were characterized by increased amounts of thymol methyl ether and gamma-terpinene. The Italian chemical profiles differentiated by the significant contributions of carvacrol methyl ether and isoterpinolene. The essential oils were also investigated for their insecticidal activity and their repellency against Pheidole pallidula (Nylander) ants and found to possess significant activity. 相似文献