Identification, isolation and characterization of the antifeedant constituent of Clausena anisata against Helicoverpa armigera （Lepidoptera： Noctuidae）  

作　　者：Olufemi O. R. Pitan O. O. Ayelaagbe Hong-Lei Wang Chen-Zhu Wang 

机构地区：[1]State Key Laboratory of Integrated Management of Pest insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing,China [2]Department of Crop Protection, University of Agriculture, Abeokuta [3]Department of Chemistry, University of Ibadan, Ibadan,Nigeria

出　　处：《Insect Science》2009年第3期247-253,共7页昆虫科学（英文版）

摘　　要：Hexane, petroleum ether, chloroform, ethyl acetate, methanol and water extracts of Clausena anisata [（Willd.） Hook E Ex Benth] leaves and roots were evaluated against Helicoverpa armigera （Hubner） for antifeedant activities. Antifeedant activity was confirmed, and was found to be higher in root extracts than those of the leaf. Chloroform and petroleum ether extracts of the root showed strongest antifeedant activities （DC50s [concentration （C） causing 50% deterrence compared with the control] 0.014% and 0.016% respectively）, and root extracts were fractionated using silica gel column chromatography. One fraction of the chloroform and one of the petroleum ether root extracts was active; and on the basis of mass spectroscopy and ^1H and ^13C nuclear magnetic resonance spectral data, the active compounds in the two fractions were confirmed to be identical, and identified as osthol [2H-1-Benzopyran-2-one, 7-methoxy-8-（3-methyl-2-butenyl）]. The highest concentration of osthol was found in the chloroform root extract. Antifeedant activities of the root extracts, as measured by DC50 values, were highly correlated with their osthol contents. Approximately 99% of the variation in bioactivity of the root extracts could be accounted for by variation in osthol content; osthol therefore, appeared to be an antifeedant component of C. anisata to H. armigera. This may provide a new approach to managing this pest.Hexane, petroleum ether, chloroform, ethyl acetate, methanol and water extracts of Clausena anisata [（Willd.） Hook E Ex Benth] leaves and roots were evaluated against Helicoverpa armigera （Hubner） for antifeedant activities. Antifeedant activity was confirmed, and was found to be higher in root extracts than those of the leaf. Chloroform and petroleum ether extracts of the root showed strongest antifeedant activities （DC50s [concentration （C） causing 50% deterrence compared with the control] 0.014% and 0.016% respectively）, and root extracts were fractionated using silica gel column chromatography. One fraction of the chloroform and one of the petroleum ether root extracts was active; and on the basis of mass spectroscopy and ^1H and ^13C nuclear magnetic resonance spectral data, the active compounds in the two fractions were confirmed to be identical, and identified as osthol [2H-1-Benzopyran-2-one, 7-methoxy-8-（3-methyl-2-butenyl）]. The highest concentration of osthol was found in the chloroform root extract. Antifeedant activities of the root extracts, as measured by DC50 values, were highly correlated with their osthol contents. Approximately 99% of the variation in bioactivity of the root extracts could be accounted for by variation in osthol content; osthol therefore, appeared to be an antifeedant component of C. anisata to H. armigera. This may provide a new approach to managing this pest.

关 键 词：active ingredient ANTIFEEDANT Clausena anisata Helicoverpa armigera osthol root 

分 类 号：S482.39[农业科学—农药学] S435.622.3[农业科学—植物保护]