germacrene-d and carvacrol

This investigation focused on the qualitative and quantitative composition of essential oil compounds of European Origanum vulgare. Extracts of 502 individual O. vulgare plants from 17 countries and 51 populations were analyzed via GC. Extracts of 49 plants of 5 populations of Israeli Origanum syriacum and 30 plants from 3 populations of Turkish Origanum onites were included to exemplify essential oil characteristics of 'high-quality' oregano. The content of essential oil compounds of European O. vulgare ranged between 0.03% and 4.6%. The monoterpenes were primarily made up of sabinene, myrcene, p-cymene, 1,8-cineole, β-ocimene, γ-terpinene, sabinene hydrate, linalool, α-terpineol, carvacrol methyl ether, linalyl acetate, thymol and carvacrol. Among the sesquiterpenes β-caryophyllene, germacrene D, germacrene D-4-ol, spathulenol, caryophyllene oxide and oplopanone were often present in higher amounts. According to the proportions of cymyl-compounds, sabinyl-compounds and the acyclic linalool/linalyl acetate three different main monoterpene chemotypes were defined. The cymyl- and the acyclic pathway were usually active in plants from the Mediterranean climate whereas an active sabinyl-pathway was a characteristic of plants from the Continental climate.

Topics: Acyclic Monoterpenes; Alkenes; Bicyclic Monoterpenes; Cyclohexane Monoterpenes; Cyclohexanols; Cyclohexenes; Cymenes; Eucalyptol; Europe; Monoterpenes; Oils, Volatile; Origanum; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Germacrane; Thymol

The essential oils of four wild growing Origanum vulgare L. (family Lamiaceae) collected from different locations in Kumaon region (Uttarakhand, India) were analysed by capillary GC and GC/MS. The comparative results of O. vulgare L. collected from four different regions showed differences in the chemical constituents of the essential oils. The oil of O. vulgare L. collected from Dhoulchina and Champawat (chemotype I) shows p-cymene (6.7-9.8%), γ-terpinene (12.4-14.0%), thymol (29.7-35.1%) and carvacrol (12.4-20.9%) as major constituents while the oil from Kilbury and Rushi village (chemotype II) shows linalool (6.7-9.7%), bornyl acetate (12.6-16.8%), β-caryophyllene (10.5-13.8%) and germacrene D (6.3-11.3%) as the major constituents. These features highlight the chemosystematics of this genus.

Topics: Acyclic Monoterpenes; Biomarkers; Camphanes; Chromatography, Gas; Cyclohexane Monoterpenes; Cymenes; Gas Chromatography-Mass Spectrometry; Geography; India; Monoterpenes; Oils, Volatile; Origanum; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Germacrane; Species Specificity; Thymol