Composition of the essential oil of Petagnaea gussonei (Sprengel) Rauschert, a relict species from Sicily (Southern Italy)

The essential oil from leaves, stems and roots of Petagnaea gussonei (Sprengel) Rauschert (= Petagnia saniculifolia Guss.), endemic to the Nebrodi Mountains (Sicily, Italy), has been analysed by the gas chromatography–mass spectrometry (GC–MS) system on two fused-silica capillary columns of different polarities. A total of 94 components were identi¼ed. Quantitative and qualitative differences were found among the analysed parts. The principal compounds from the leaves oil were found to be (w/w%) germacrene D (19.9%), g-muurolene (7.96%) and caryophyllene oxide (6.85%), while in the oil from stems hexadecanoic acid (23.40%), germacrene D (18.50%) and (Z,Z)-9,12-octadecadienoic acid (13.20%) were the main constituents. The oil from the roots presented instead hexadecanoic acid (21.50%), 4- vinylguaiacol (6.81%) and germacrene D (5.22%) as the major constituents. A comparison with essential oils from taxonomically-related species of P. gussonei is reported. This is the ¼rst report on the chemical composition of this species.