Chemical variability and antioxidant activity of Eryngium maritimum L. essential oils from Corsica and Sardinia

The chemical compositions of Corsican and Sardinian Eryngium maritimum L. essential oils were investigated using column chromatography, gas chromatography with flame ionization detection and gas chromatography-mass spectrometry in electron impact mode. Sixty-three compounds were identified accounting for 85.8-95.7% of the total amount. With germacrene D (13.7-45.9%), three uncommon oxygenated sesquiterpenes, 4H-cadin-9-en-15-al (18.4-27.6%), 4H-cadin-9-en-15-ol (2.2-14.3%) and 4H-muurol-9-en-15-al (4.3-9.3%), were identified as main components of the essential oils obtained from the plant aerial parts. Relative to these, essential oils from the roots differed drastically with high contents of 2,4,5-trimethylbenzaldehyde (39.8%), 2,3,6-trimethylbenzaldehyde (29.0%) and -muurolene (23.5%). The chemical variability of Corsican and Sardinian E. maritimum essential oils was studied using statistical analysis. A direct correlation between the island of origin of the sample essential oils and their chemical compositions was assessed. Corsican essential oils exhibited higher amounts of hydrocarbon terpenes than Sardinian samples. Relative to other Eryngium species, Corsican and Sardinian E. maritimum essential oils exhibited original compositions with sesquiterpene aldehydes. These compounds, together with total essential oil, were tested for antioxidant properties using the DPPH and ABTS radical-scavenging activity tests. No meaningful activity could be attributed to sesquiterpene aldehydes and the corresponding alcohols but the total essential oil and the oxygenated fraction of E. maritimum both demonstrated strong antioxidant properties. Copyright (c) 2013 John Wiley & Sons, Ltd.