Chemical ecology of insect and Piperaceae species

Author(s)

Clécio Sousa Ramos

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2006-09-12

Examining board members

Massuo Jorge Kato; Leandro Helgueira de Andrade; Alberto José Cavalheiro; Frederico Guaré Cruz; Clélia Ferreira Terra

• Advisor: Massuo Jorge Kato
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Indexed in: Banco de Dados Bibliográficos da USP-DEDALUS; Biblioteca Digital de Teses e Dissertações - USP
• Location: Universidade de São Paulo. Biblioteca do Conjunto das Químicas; CQ T/547.7; R175e

Abstract

The study was presented in six chapters that included several aspects of chemical ecology of insects and Piperaceae species as following: The Chapter 1 describes taxonomical aspects, natural history of the insects and field observation and the organization of hosts Piperaceae according to the observed feeding preferences of the associated insects. It was observed strong chemical specificity of Coleoptera and Homoptera species by Piper aduncum, P. gaudichaudianum, P. arboreum and P. hispidum which contain prenylated benzoic acids. The Lepidoptera showed preference for species containing neolignanas and/or lignanas such P. regnellii and P. solmsianum. The Chapters 2 and 3 (coleopterous - beetles and lepdopterous-butterflies, respectively), were addressed for the studies of biotransformation reactions, sequestration and attractive assays. The study of possible factors present attractions in essential oils was investigated by the use of electrophysiological essays. It were observed several reactions as esterification, hydrolyses and ozonolyse-type for lignans, neolignans, phenylpropanoids and amides occurring in from species of Piperaceae during the digestive process of the butterflies and of beetles. It was observed sequestration of neolignans of P. regnellii by larvae of Heraclides hectorides and prenylated of benzoic acids from roots of P. gaudichaudianum by the larva of the beetle Naupactus bipes. The experiments of EAG using antennas of the beetle N. bipes showed that the oils of P. gaudichaudianum, P. regnellii and P. hispidum were active and such results were in agreement with field observations and the most intense response was observed for the females in relation to the response for the males. The analyses of GC/EM-EAD allowed the determination of the bio-actives compounds as the monoterpenes α-pinene, β-pinene and β-mircene. The Chapter 4 describes the homopteros species that have specificity for the P. gaudichaudianum, P. arboreum and P. aduncum accumulative of prenylated benzoic acids. Further determinant factors for specificity included: low percentage of secondary metabolites in saps, high percentage of micro-nutrients and low percentage of macro-nutrients, absence of lignans or neolignans in the saps, lignifications with predominance of siringyl residues (S) which confer a pattern related to Angiosperms. The Chapter 5 describes the determination and structural characterization of the 49 secondary metabólitos involved in this study. The Chapter 6 shows the study of stability versus natural occurrence of tetrahydrofuran lignans was carried out due to the rare occurrence of all-cis configuration. The study of the stability for the ten possible stereoisomers for the tetrahydrofuran lignans was through the calculation of the functional of density, B3LYP, with the base 6-316(dp), it showed that the all-cis configuration is less stable than the all-trans tetrahydrofuran lignans. (AU)