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Myrtus communis L. grows wild all around the Mediterranean basin and on the islands. Myrtle leaf essential oil has a characteristic pleasant odour although various compositions, which differ by the content of monoterpene esters, have been reported. Fractionation of an essential oil sample from Corsica, followed by analysis of the chromatographic fractions by GC(RI) and 13 C NMR allowed the identification of four C8–C10 esters, first identified 20 years ago in a Spanish essential oil sample and since that time very scarcely reported, despite the tremendous amount of work carried out on the composition of myrtle leaf essential oil. Therefore, the composition of 63 samples of M. communis L. leaf essential oil isolated from myrtle growing wild in various Mediterranean countries (Corsica, Sardinia, Portugal, Morocco, Algeria and Tunisia) has been investigated by GC(RI) and 13 C NMR and the four C8–C10 esters have been identified in all the samples. The occurrence of these esters merits great attention, since they contribute to the pleasant odour of the myrtle essential oil. In parallel, 3,3,5,5,8,8‐hexamethyl‐7‐oxabicyclo[4.3.0]non‐1(6)‐ene‐2,4‐dione has been identified in all the samples. Copyright © 2012 John Wiley & Sons, Ltd.

Abstract:In order to get better knowledge about the volatiles produced by Xanthocyparis vietnamensis, a species recently discovered in Vietnam, its wood oil has been analyzed by a combination of chromatographic (GC, CC) and spectroscopic (GC-MS, 13 C-NMR) techniques. Forty components that accounted for 87.9% of the oil composition have been identified. The composition is dominated by nootkatene (20.7%), 11,12,13-tri-nor-eremophil-1(10)-en-7-one (17.2%), γ-eudesmol (5.1%), nootkatone (4.7%), valencene (3.5%) and 13-nor-eremophil-1(10)-en-11-one (2.6%). The structure of two new compounds-10-epi-nor-γ-eudesmen-11-one and 12-hydroxy-isodihydroagarofuran-has been elucidated, while 11,12,13-tri-nor-eremophil-1(10)-en-7-ol is reported as a natural product for the first time. The composition of X. vietnamensis wood oil varied drastically from those of leaf oils, dominated by hedycaryol (34.4%), phyllocladene (37.8%) or by pimara-6(14)-15-diene (19.4%).