Comparison of the Chemical Composition of Essential Oils Isolated by Water-steam Distillation and Hydrodistillation from Garden Thyme (Thymus vulgaris L.)

The aim of the studies conducted in 2010-2012, was to compare the chemical composition of essential oils isolated from garden thyme (Thymus vulgaris L.) by water-steam distillation and hydrodistillation in Deryng apparatus. Analysis of the isolated oils by GC-MS revealed the presence of 35 different components represented mainly by oxygenated monoterpenes (67.30-89.89 %), monoterpene hydrocarbons (2.43-26.55 %) and sesquiterpene hydrocarbons (2.93-4.94 %). Thymol (57.14-71.29 %) and carvacrol (10.38-20.40 %) were the main constituents identified in water-steam distilled oil, while thymol (41.34-52.23 %), carvacrol (10.12-16.73 %), p-cymene (9.10-12.12 %) and gamma-terpinene (6.12-10.20 %) dominated in hydrodistilled oil. On the basis of the obtained data it was proved that the distillation method had a significant effect on the chemical composition of garden thyme essential oil. There was no significant effect of distillation method on essential oil content found.