Antifeedant/Insecticidal Terpenes from Asteraceae and Labiatae Species Native to Argentinean Semi-arid Lands

Abstract

To validate the potential as added-value resources of Asteraceae and Labiatae species of Argentinean semi-arid lands, we have selected 13 of their major terpenoids belonging to several chemical classes and tested their insect antifeedant and toxic activity on the herbivorous insects Spodoptera littoralis and Leptinotarsa decemlineata. The antifeedant effects of the test compounds were structure-and species-dependent. The most active antifeedant to L. decemlineata was the eudesmane sesquiterpene γ-costic acid (13), followed by the labdane diterpene 2α,3α-dihydroxycativic acid (8), the clerodane diterpenes 6-acetylteucjaponin B (5), bacchotricuneatin A (1), bartemidiolide (7), butanolide (4), and the sesquiterpenes ilicic acid (11) and tessaric acid (10) (eudesmane and eremophilane type, respectively). S. littoralis was only affected by the clerodanes and showed the strongest response to salviarin (3) and 5, followed by hawtriwaic acid (6) and 12-epi-bacchotricuneatin A (2). Orally injected S. littoralis larvae were negatively affected by 5. Most of the diterpenes had selective cytotoxic effects to insect-derived Sf9 cells with the clerodane 1 being the most active, followed by the eudesmane costic acid (12), the only cytotoxic sesquiterpene. None of these compounds was cytotoxic to mammalian CHO cells.

Sesquiterpenoids in subtribe Centaureinae (Cass.) Dumort (tribe Cardueae, Asteraceae): Distribution, 13C NMR spectral data and biological properties

“…Furthermore costic acid (124) had selective cytotoxic effects toward insect-derived Sf9 cells (Gonzalez-Coloma et al, 2005).…”

“…Also dehydrocostus lactone (142), isolated from the dichloromethane extract of the Portuguese liverwort T. lorbeeriana, presented larvicidal activity against A. aegypti (Gonzalez-Coloma et al, 2005).…”

Plant secondary metabolites from Argentinean semiarid lands: bioactivity against insects

“…Taking into account the grain production of Argentina it is an interesting insect model to use in antifeedant activity studies toward clerodane diterpenes. In this order a considerable number of this kind of compounds (23-49) has been isolated in our laboratory from plants of the Asteraceae and Labiatae families Luco et al 1994;Gallardo Varas et al 1996;Ceñ al et al 1997;Enriz et al 2000;Simirgiotis et al 2000;Cifuente et al 2002;Gonzá lez Coloma et al 2005;Juan et al 2006). From this set of diterpenes, compounds 50-55 were prepared by chemical transformations.…”

“…Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) (Juan et al 2006), S. littoralis (Boisduval), and L. decemlineata (Gonzá lez Coloma et al 2005) were used as insect model in some opportunities. Toward T. molitor larvae using carrot discs as food source , the most important values of Percentage of Feeding Inhibition (PFI) were observed for compounds 23 (PFI = 30.0), 24 (PFI = 31.2), 26 (PFI = 22.6), and 35 (PFI = 25.0).…”

Activities and Novel Applications of Secondary Metabolite Coumarins

“…Plants are a good potential source of such compounds, since many plant species have a defense mechanism and produce secondary metabolites in order to survive in the ecosystem. The plant families Asteraceae (Chiasson et al, 2001;Gonzalez-Coloma et al, 2005), Milliaceae (Gupta and Misra, 2006;Prasad et al, 2006;Sharma et al, 2006), and Apiaceae (Kang et al, 2006) are known to have insecticidal constituents. In sunflower, it was demonstrated that feeding damage of the plant by sunflower beetle Zygogramma exclamationis induced coumarin biosynthesis.…”