Composition and antioxidant activity of essential oils of Lippia origanoides H.B.K. grown in Colombia

Abstract

Microwave-assisted hydrodistillation, simultaneous distillation-solvent extraction, and supercritical fluid extraction, were used to isolate secondary metabolites from two Lippia origanoides chemotypes growing wild in Colombia. Compound identification was based on chromatographic and spectroscopic criteria. The main components identified in the essential oil of one chemotype were carvacrol (44.4-51.8%) and p-cymene (8.8-10.1%). Those of the other chemotype were p-cymene (11.3-15.7%) and 1,8-cineole (6.8-10.9%). The last one constitutes a new chemotype, characterized by its low thymol and carvacrol contents and very low antioxidant activity. The radical scavenging activity of the essential oil of the first chemotype was higher than that of butylated hydroxytoluene (BHT) and similar to that of α-tocopherol.