Essential oil composition of two Greek cultivated Sideritis spp.

Abstract

Essential oil composition of cultivated Sideitis raeseri Boiss. & Heldr. and Sideritis scardica Griseb. from three different restricted areas of Kozani (central Greece) have been studied. The plant materials were commercially available. The essential oils were obtained by hydrodistillation in a modified Clevenger-type apparatus, and their analyses were performed by GC-MS. Identification of the components was made by comparison of mass spectra and retention indices with literature records and by co-chromatography with authentic compounds. Monoterpene hydrocarbons constituted the main fraction of S. raeseri from Polirraxo (Kozani) and of S. scardica from Chromio (Kozani), while sesquiterpene hydrocarbons were the main group of S. raeseri from Metamorfosis (Kozani) and S. scardica from Metamorfosis (Kozani). Despite the different cultivations, some constituents were found even in different percentages in both samples of S. scardica: α-pinene, b-pinene, cis-caryophyllene, bicyclogermacrene and germacrene D. It is noteworthy that the two samples of S. raeseri have totally different main constituents, which could be related to the different cultivation conditions, as well as to known tendency of some Sideritis species to hybridize.