Planta Med 2015; 81 - PW_199
DOI: 10.1055/s-0035-1565823

Oxygen radical absorption capacity of Lippia origanoides (thymol and phellandrene chemotypes) and Turnera diffusa essential oils and extracts

E Stashenko 1, Y Córdoba 1, JR Martínez 1
  • 1Research Center for Biomolecules, CENIVAM, Universidad Industrial de Santander, Bucaramanga, Colombia

Damiana (Turnera diffusa) and Mountain oregano (Lippia origanoides) are shrubs that grow wild in semi-arid terrains of Central and northern South America. Three L. origanoides chemotypes have been found, characterized by their different essential oil main constituents (thymol, carvacrol and phellandrene). GC-MS analysis of essential oils (EO) and extracts (obtained with supercitical CO2) from stems and leaves of T. diffusa and L. origanoides (thymol and phellandrene chemotypes) showed that the secondary metabolites common to these aromatic plants were: α-pinene (0.5 – 1.8%), limonene (0.2 – 37.8%), linalool (0.2 – 1.1%), trans-β-caryophyllene (1.0 – 26.4%), α-humulene (4 – 2.4%), caryophyllene oxide (3 – 7.2%), and germacrene D (0.05 – 37.68%). Dehydrofuquinone (52.3%) and drima-7,9-diene (4.4%) were the main components of damiana oil. The oxygen radical absorption capacity (ORAC) of a L. origanoides (phellandrene chemotype) extract obtained with supercritical CO2 showed a remarkably high value (4130 ± 29 micromol Trolox/g substance), attributed to its high pinocembrin content. Lower ORAC values were obtained for L. origanoides (thymol chemotype) EO (3710 ± 10 micromol Trolox/g sample), followed by L. origanoides (phellandrene chemotype) EO (1260 ± 29 micromol Trolox/g sample) and damiana EO (813 ± 9 micromol Trolox/g sample). EO were obtained by microwave radiation-assisted hydrodistillation. Extracts were obtained with CO2 at 400 bar, 50 g/min and 10% ethanol in a Thar SFE-2000 – 2-FMC50 system; extract fractions were collected at 40 and 80 bar. The separation and identification of secondary metabolites was performed on an Agilent Technologies GC 6890 with 5973 mass selective detector (EI, 70 eV). Chromatographic columns DB-5 and DB-WAX (60 m × 0.25 mm, ID × 0.25 mm) were used. The ORAC assay was performed in a Turner Biosystems multiplate reader. Trolox® was used as a reference standard for these measurements.