Essential oil of Eryngium L. species from new South Wales (Australia)

The essential oils from aerial parts of five Eryngium species of New South Wales have been examined by GC and GUMS. The oil of Eryngium expansum F. Muell was characterized by a high amount of 7-epi-alpha-selinene (38.3%), cis-beta-guaiene (10.8%), 2,3,6-trimethylbenzaldehyde (8.0%) and (E,E)-alpha-farnesene (7.3%). The leaf oil of E. pandanifolium Chain. et Schlecht contained bornyl acetate (20.8%), beta-selinene (13.8%), alpha-selinene (11.3%) and alpha-muurolene (8.0%) as the main compounds, while the fruit oil was characterized by heptanol (11.5%) and beta-selinene (9.2%). The principal compounds of E. rostratum Cav. were found to be spathulenol (20.0%) and beta-bisabolol (8.6%) in the leaf oil while beta-bisabolol (65.3%) was the main component in the fruit oil. beta-Caryophyllene (20.3%), gennacrene D (19.2%) and alpha-humulene (8.8%) were found to be the major compounds of E. vesiculosum Labill. Two populations of an undescribed species (E. sp. 1, E. sp. 2) of this genus were also studied, the principal compounds being a-pinene (14.5-46.2%), bicyclogermacrene (7.1-16.4%), cubebol (0.6-9.0%) and spathulenol (0.8-8.7%). This is the first report on the essential oil composition of these Australian species.