Acinos mayoranifolius (Mill.) Silic is endemic, spread across the western border area of Croatia
and Herzegovina and the western part of Montenegro. It is a distinctly Mediterranean mountainous
species. It inhabits open limestone rocky terrains, rims of karst forests, on heights between 20 and
1400m (Silic, 1979, 1984). A. majoranifolius is distinguished from the rest of the Acinos species by its
aroma, and therefore the composition of its essential oil is presented in this work.
We have studied the essential oils of three populations of A. majoranifolius collected from different
localities in Western Montenegro: mountain Orjen, Njegusi and Lijeva Rijeka. The samples were
gathered in the flowering period. The essential oil was obtained by hydrodistillation from the dried
aerial parts of the plants. The analyses of the oils were carried out using GC/MS. The identification of the compounds was based on comparison of their Kovats indices (KI), their retention times (RT) and mass spectra with those obtained from authentic samples and/or the MS library (Adams, 1995). The yield of the essential oils was between 0.5% and 0.6%. Pulegone was the main component of all the oils (65.4%-81.3%). The Mt. Orjen and Njegusi populations had a high content of isomenthone (11.4% and 15.4%), while this compound was detected only in traces in the Lijeva Rijeka population.Isopulegone and caryophyllene oxide were found in similar concentrations in all populations
