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Chemical Composition of the Leaf and Branch Oils of Perymenium grande Hemsl. var. nelsonii (Robins. & Greenm.) Fay (Asteraceae-Heliantheae) from Costa Rica

José F. Cicció and Carlos Chaverri

Centro de Investigaciones en Productos Naturales (CIPRONA) and Escuela de Química,Universidad de Costa Rica, San José, Montes de Oca, San Pedro, 11501-2060 Costa Rica

Abstract: The chemical composition of the essential oils of Perymenium grande Hemsl. var nelsonii (Robins. & Greenm.) Fay (Asteraceae) growing wild in Costa Rica was analyzed by capillary GC-FID and GC-MS. One hundred and two and one hundred and seven compounds were identified in the leaf and branch oils, respectively, corresponding to about 94.9% and 79.3% of the total amount of the oils. The leaf oil consists mainly of sesquiterpene hydrocarbons (50.3%) and monoterpene hydrocarbons (33.8%). The major components of the leaf oil were b -caryophyllene (30.5%), b -pinene (12.4%), germacrene D (10.0%), b -phellandrene (9.8%) and a -pinene (8.9%). The branch oil consists mainly of sesquiterpene hydrocarbons (38.3%), monoterpene hydrocarbons (21.6%) and oxygenated sesquiterpenes (20.4%). The major components of the branch oil were a -isocomene (13.8%), a -pinene (7.4%), b -isocomene (5.2%), b -pinene (4.3%) and b -caryophyllene (4.3%). This is the first report of the chemical composition of the essential oils obtained from this species.

Keywords: Perymenium grande; essential oil composition; β-caryophyllene; a -isocomene ; b -pinene.