Analysis of the volatile fraction of Teucrium marum L.

Volatile components of Teucrium marum from Corsica were investigated using a combination of analytical techniques. Analysis of essential oils obtained by hydrodistillation was performed using capillary GC-RI, GC-MS and C-13 NMR spectroscopy after fractionation on column chromatography. The emitted volatile fractions from full aerial parts and separated organs of fresh T. marum were investigated using HS-SPME/GC-RI and HS-SPME/GC-MS. The intra-species variations of the chemical compositions of essential oils and volatile fractions from 25 Corsican sample locations were investigated using statistical analysis. The main essential oil components were caryophyllene oxide (0.4-20.5%), (E)-beta-caryophyllene (0.9-18.9%), (E)-alpha-bergamotene (1.0-21.5%), (3Z,6E,10E)-alpha-springene (1.1-17.8%), beta-bisabolene (0.4-14.7%), beta-sesquiphellandrene (0.9-10.9%) and estragole (0.5-7.0%), while dolichodial (20.0-83.4%), (E)-alpha-bergamotene (0.2-20.6%), (E)-beta-caryophyllene (0.3-23.1%), dolicholactone (0.4-20.9%), beta-bisabolene (0.2-10.0%), estragole (1.1-10.5%) and beta-sesquiphellandrene (0.2-8.3%) were the main volatiles emitted by the plant. The C-13-NMR data of (3Z, 6E, 10E)-alpha-springene and its occurrence in T. marum essential oils are reported for the first time. The importance of the sample preparation step is discussed through the absence/occurrence of dolichodial in both liquid and gaseous matrices studied, respectively. Copyright (C) 2012 John Wiley & Sons, Ltd.