Chemical composition of the essential oil from aerial parts of Stachys palustris L. (Lamiaceae) growing wild in Southern Italy

The paper reports the composition of the essential oil from aerial parts of Stachys palustris L. (Lamiaceae) from Southern Italy. The essential oil was extracted by hydrodistillation from selected plants and its chemical composition was determined by the GC-MS system on two fused-silica capillary columns of different polarity. The mass fraction of oil was 0.21 % on a dry weight basis. Altogether, 92 compounds were identified accounting for 93.6 % of the total oil, which was characterized mainly by carbonylic compounds (25.4 %), fatty acids and their esters (24.2 %), along with sesquiterpenoidic compounds (16.0 %) and phenols (11.2 %). The major components of the sample were caryophyllene oxide (7.8 %), hexahydrofarnesyl acetone (7.4 %), hexadecanoic acid (6.8 %), (Z,Z,Z)-9,12,15-octadecatrienoic acid (6.7 %), (Z)-phytol (6.4 %), thymol (5.8 %), p-methoxyacetophenone (5.1 %), 4-vinylguiacole (3. %), tetradecanoic acid (3.8 %), (E)-caryophyllene (3.6 %), b-ionone (3.3 %) and b-damascenone (3.0 %)