Identification and comparison of chemical composition of the essential oils of Bunium cylindricum (Boiss. & Hohen.) Drude and Bunium rectangulum Boiss. & Hausskn.

The genus Bunium comprised of 14 species in Iran, two of them (B. wolfi and B. lurestanicum) are endemic. Among these species, only B. persicum is famous and used in medicinal and nutrition industries. In this research, two other species of Bunium named as B. cylindricum (Boiss.& Hohen.) Drude and B. rectangulum Boiss.& Hausskn., were studied. At first, different parts of these plants were collected from their habitats. Different parts were separated and then dried. The dried plant materials were subjected to hydro-distillation for obtaining the essential oils. The oils were analyzed by GC and GC/MS. Seventeen components were characterized in the oil of aerial parts of B. cylindricum at flowering stage. Germacrene D (31.2%), dill apiol (26.9%), E- caryophyllene (11.6%) and germacrene B (7.1%) were the main constituents. 20 compounds were identified in the seed oil of B. cylindricum with dill apiol (25.8%), E- caryophyllene (15.4%), globulol (12.2%), spathulenol (7.2%) and germacrene D (6.6%) as main components. 11 compounds were identified in the seed oil of B. rectangulum with dill apiol (63.3%), Germacrene D (22.4%) and E-caryophyllene (5.1%) as main components. 21 components were characterized in the flower oil of B. rectangulum. Germacrene D (36.7%), Dill apiol (11.1%), bicyclogermacrene (16.5%) and E-caryophyllene (15.9%) were the main constituents. The results showed that the essential oils of both species contained mainly sesquiterpens, but the percentages of these compounds were different.