No abstract

The essential oils obtained by water distillation from the aerial parts of two Helichrysum italicum ssp. growing in Corsica (France), Tuscany and Sardinia (Italy) were analysed by GC-RI and GC-MS. The essential oils prepared from Corsican and Tuscan Helichrysum italicum subsp. italicum exhibited two different compositions. Corsican oils were characterized by the pre-eminence of oxygenated compounds: neryl acetate (major compound), neryl propionate, nerol, acyclic ketones and β-diketones. Conversely, Tuscan oils were found to exhibit higher contents of hydrocarbons (α-pinene, β-caryophyllene, α-and β-selinenes). The comparison of essential oils hydrodistilled from Corsican and Sardinian Helichrysum italicum subsp. microphyllum showed almost similar chemical compositions. The main constituents were: neryl acetate, nerol, neryl propionate, linalool, eudesm-5-en-11-ol and γ -curcumene.

The constituents of the essential oil of Stachys glutinosa L. were investigated for the ®rst time. In a ®rst part, we studied a collective oil following a methodology which combined chromatographic techniques (CC, GC) with spectroscopic techniques (MS, 13 C-NMR). Sixty-four constituents (91% of the total composition) were identi®ed. The major compounds were terpinen-4-ol (13.1%), a-pinene (10.1%), a-terpineol (8.4%), b-phellandrene (6.8%) and g-terpinene (6.1%). In a second part, we investigated 53 oil samples obtained from individual plants collected widely in Corsica, by GC±RI and GC±MS. The essential oils of S. glutinosa displayed a wide infraspeci®c chemical variability.