Composition of the essential oil of Melanoselinum decipiens (Schrad. & Wendl.) Hoffm., an endemic species of the Madeira and Azores archipelagos

The composition of the essential oils from the aerial parts of Melanoselinum decipiens (Schrad, & Wendl.) Hoffm., collected during the vegetative phase on Madeira and on the Azores, respectively, was analysed by GC and GC-MS. Both oils consisted mainly of monoterpenes (87% and 86% for Madeiran and Azorean oils, respectively), beta-pinene (72%) and limonene (82%) being the main components of the Madeiran and Azorean oils, respectively. The sesquiterpene fraction attained 7% of the oil isolated from the Madeiran plants, whereas 5% was found in the oil isolated from the Azorean M. decipiens, the latter consisting only of hydrocarbons. This oil contained a higher non-terpenoid fraction, dominated by n-nonane (4%), than that of the Madeiran M. decipiens (7% and 1%, respectively). (C) 1997 John Wiley & Sons, Ltd.