Extraction of Baccharis oil by supercritical CO2

Baccharis dracunculifolia, "Vassoura", is a shrub with spontaneous occurren ce in Brazil, Uruguay, Argentina, Paraguay, and Bolivia. The Vassoura oil, valuable in the perfumery industry for its exotic aroma, presents variation s in composition depending on the geographical origin and extraction proces s. The commercial importance is related to the oxygenated fraction content, specifically to (E)-nerolidol and spathulenol. In this work we study the d ependence of the Vassoura oil composition, obtained by supercritical CO2 (S CCO2) extraction, with the following parameters: pressure, temperature, SCC O2 flow, equilibrium, and extraction times. The flexibility of the extracti on process using SCCO2 allowed one to study the Vassoura oil composition as a function of the extraction parameters. Higher concentrations of (E)-nero lidol and spathulenol were obtained in the following experimental condition s: pressure, 10 MPa; temperature, 323.15 K; equilibrium time, 10 min; extra ction time, 20 min; SCCO2 flow, 1.0 mL/min. The results were compared with those obtained by hydrodistillation in laboratory conditions. The evaluatio n of the composition for each extract was performed by gas chromatography a nd gas chromatography-mass spectrometry.