Supercritical carbon dioxide extraction of volatiles from Satureja fruticosa Beguinot

Dried flowers and leaves of Satureja fruticosa Beguinot were submitted to supercritical CO2 extraction (SFE), followed by a two-stage fractional separation. The extraction was carried out at 40 degrees C in a flow apparatus, provided with a 11 extraction vessel and two separators of 0.271 each. Conditions of extraction, such as pressure, particle size of plant material and CO2 flow rate, were studied in order to assess their influence on the yield and composition of the volatiles. The best conditions of extraction were 90 bar pressure at 1.32 kg/h CO, flow rate and a plant material particle size of 0.5 mm. The SFE volatiles obtained and the essential oil isolated by hydrodistillation (HD) were analysed and compared by GC and GC-MS. The oxygen-containing monoterpenes, pulegone (33-36% for SFE and 40-41% for HD), isomenthone (14-18% for SFE and 21% for HD), piperitenone (11-12% for SFE and 9-11% for HD) and piperitenone oxide (11-13% for SFE and 7-9% for HD) were the dominant components in all samples. Copyright (c) 2007 John Wiley & Sons, Ltd.