title: Antifeedant activity of fatty acid esters and phytosterols from Echium wildpretii.
abstract: Crude extracts and fractions from Echium wildpretii H. Pearson ex Hook. f. subsp. wildpretii (Boraginaceae) have been tested against insect species Spodoptera littoralis, Leptinotarsa decemlineata, and the aphids Myzus persicae, Diuraphis noxia, Metopolophium dirhodum, Rhopalosiphum maidis, and Rhopalosiphum padi. The EtOH extract and the lipid and steroidal fractions of E. wildpretii exhibited significant antifeedant activities against the aphids and L. decemlineata. Two bioactive mixtures composed of fatty acid esters and n-alkanes were obtained from the lipid fraction. The bioguided fractionation of the steroidal fraction resulted in the isolation of glutinol, β-sitosterol, (3β,7α)-stigmast-5-ene-3,7-diol, and (3β,7α)-7-methoxystigmast-5-en-3-ol. The latter two compounds exhibited potent antifeedant activities against L. decemlineata indicating that the presence of an O-bearing C(7) was responsible for the activities of these molecules.
authors.affiliation: Instituto de Ciencias Agrarias, CSIC, Serrano 115-dpdo, ES-28006 Madrid.
authors.forename: Omar
authors.initials: O
authors.lastname: Santana
authors.forename: Matias
authors.initials: M
authors.lastname: Reina
authors.forename: Braulio M
authors.initials: BM
authors.lastname: Fraga
authors.forename: Jesús
authors.initials: J
authors.lastname: Sanz
authors.forename: Azucena
authors.initials: A
authors.lastname: González-Coloma
mesh_terms: D000818:Animals; D001042:Aphids / Q000187:drug effects; D001517:Coleoptera / Q000187:drug effects; D036661:Echium / Q000737:chemistry*; D004952:Esters; D005227:Fatty Acids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D007306:Insecticides / Q000737:chemistry / Q000302:isolation & purification; D010840:Phytosterols / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry; D018411:Spodoptera / Q000187:drug effects
chemical_list: D004952:Esters; D005227:Fatty Acids; D007306:Insecticides; D010840:Phytosterols; D010936:Plant Extracts