ESSENTIAL OIL CHEMICAL-COMPOSITION OF WILD POPULATIONS OF ITALIAN OREGANO SPICE (ORIGANUM-VULGARE SSP. HIRTUM (LINK) IETSWAART) - A PRELIMINARY EVALUATION OF THEIR USE IN CHEMOTAXONOMY BY CLUSTER-ANALYSIS - 1 - INFLORESCENCES

Twenty-four steam-distilled samples of essential oils from inflorescen ces from Origanum vulgare ssp. hirtum (Link) Ietswaart growing wild in Calabria, southern Italy, were analyzed by gas chromatography and gas chromatography/mass spectrometry. A total of 56 compounds were identi fied. The main components of the essential oil were thymol and carvacr ol, while their biogenetic precursors, p-cymene and gamma-terpinene, w ere the most aboundant monoterpenes. The relative amounts of the two m ain constituents were comparable to the literature data on this specie s. Four chemotypes were identified in Calabria on the basis of the phe nolic content, i.e., thymol, carvacrol, thymol/carvacrol, and carvacro l/thymol chemotypes. The first chemotype was the most frequent. A sign ificant variability of composition possibly correlated with the indivi dual genotypes was observed.