Chemical and antimicrobial analyses of essential oil of Lippia origanoides H.B.K

Lippia origanoides H.B.K. (Verbenaceae) is a plant known in Oriximiná (Brazil) as “Salva-de-Marajó”. Its leaves are widely used as of a spice in cooking and in traditional medicine. The chemical composition of the essential oil obtained from its leaves, analyzed by GC and GC/MS, showed a high content of oxygenated monoterpenes (66.0%), carvacrol (38.6%) and thymol (18.5%) being the major constituents. Considering that previous studies on the same plant species showed carvacrol as a trace or absent compound, we propose the existence of a new chemotype for this species. A high carvacrol content in the essential oil determines the plant’s suitability for the preparation of oregano condiment. The antimicrobial activity of this essential oil was determined by the drop diffusion method, showing highly significant inhibition zones for all microorganisms tested.