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Bio-pesticidal and Antimicrobial Coumarins from Angelica dahurica (Fisch. Ex Hoffm) Qian Xie, Shun-Xiang Li, Duan-Fang Liao, Wei Wang, Babu Tekwani, Hui-Yong Huang, Abbas Ali, Junaid ur Rehman, Kevin K. Schrader, Stephen O. Duke, Charles L. Cantrell and David E. Wedge Programa de Pós-Graduação em Química, Universidade Federal do Pará, 66075-900 Belém, PA, Brazil Programa de Pós-Graduação em Química, Universidade Federal do Maranhão, 65080-040 São Luis, MA, Brazil Departamento de Ciências Naturais, Universidade do Estado do Pará, 66113-200 Belém, PA, Brazil Coordenação de Botânica, Museu Paraense Emílio Goeldi, 66040-170 Belém, PA, Brazil Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, 68035-110 Santarém, PA, Brazil
Abstract: The air-dried aerial parts of Croton campestris, C. chaetocalyx, C. eriocladus, and C. glandulosus, with occurrence in the Eastern Brazilian Amazon, yielded essential oils, and their volatile constituents were analyzed by GC and GC-MS. Sesquiterpenes, both hydrocarbons and oxygenated, were the most highly represented classes in the oils: the former ranging from 55.3% to 85.1%, and the latter varying from 7.2% to 33.2%. The oils were separated into two groups using hierarchical cluster analysis whose main constituents were β-caryophyllene, germacrene D, γ-elemene, β-elemene, α-humulene and δ-elemene (Group A, C. campestris and C. eriocladus); and spathulenol, bicyclogermacrene, δ-elemene, germacrene D, β-caryophyllene and δ-cadinene (Group B, C. chaetocalyx and C. glandulosus). Percentage of sesquiterpene hydrocarbons was higher in Group A (83-85%) than in Group B (55-63%). However, regarding the oxygenated sesquiterpenes, it was reversed, being bigger in Group B (28-33%) than in Group A (7-8%). Percentage of similarity in Group A was 92% and in Group B it was 86%. These chemotaxonomic results showed a significant contribution for the better botanical knowledge of these four Croton species occurring in North Brazil. Keywords: Croton spp; Euphorbiaceae; Essential oil composition; sesquiterpene compounds; Hierarchical Cluster Analysis. © 2015 ACG Publications. All rights reserved.
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