The essential oil was obtained by steam distillation, using a Clevenger apparatus, from the pericarp of the fruit of Zanthoxylum lepidopteriphilum from Ecuador. The qualitative and quantitative analyses were performed by gas chromatography coupled with mass spectrometry (GC-MS) and flame ionization detection (GC-FID) on two capillary columns with non-polar DB-5ms and a polar HP-INNOWax stationary phase. Thirty-three components were identified, accounting for 99.62% and 99.30% total essential oil. The essential oil was dominated by oxygenated monoterpenes (90.21-89.21%), respectively. The main constituents of the essential oil were α-thujone (70.26-70.38%), β-thujone (10.78-10.90%), terpinen-4-ol (4.15-4.06%), and sabinene (3.60-4.02%). Enantioselective analysis by GC was realized on a β-cyclodextrin-based chiral column (2,3-diethyl-6-tert-butyldimethylsilyl-β-cyclodextrin) in this analysis, determining three couples of enantiomers, which exhibited the compound (1R,4S,5S)-(+)-α-thujone with an enantiomeric excess of 84.40%.
Keywords: Zanthoxylum lepidopteriphilum; α-thujone; β-thujone.