Chemical Composition of the Essential Oil of Ziziphora capitata L. from Iran

The chemical composition of the hydrodistilled essential oil of the aerial flowering parts of Ziziphora capitata L. from Iran was analyzed by GC and GC-MS. Forty-two components representing 97.2% of the total oil were identified. The main constituents of the oil were germacrene D (21.3%), limonene (7.8%), beta-caryophyllene (7.5%), bicyclogermacrene (5.5%) and spathulenol (4.5%). Sesquiterpene hydrocarbons (46.9%) and oxygenated sesquiterpenes (24.8%) were the predominant portion of the oil. Regarding main component of the oils of different Ziziphora species, Z. capitata with containing germacrene D as major constituent in contrast to pulegone for other species were chemically different.