Comparative Analysis of the Oil and Supercritical CO₂ Extract of Ferula communis L.

Abstract

Flowerheads of Ferula communis L. were used for supercritical extraction with carbon dioxide to isolate the corresponding volatile concentrate. It was isolated by supercritical CO₂ extraction coupled to a fractional separation technique. The process was carried out operating at 100 bar and 50°C in the extraction vessel, at 100 bar and below −5°C in the fi rst separator to selectively precipitate the cuticular waxes and at a pressure between 15 and 20 bar and temperatures in the range of 15°-21°C in the second separator to recover the volatiles. GC/MS analysis of the extract allowed the identification of the volatile concentrate composition.

The main constituents in the extract were α-gurjunene, β-gurjunene, α-selinene and β-selinene. A comparison with the oil obtained by hydrodistillation is also given. The differences observed between the composition of the SFE volatile concentrate and of the hydrodistilled oil were relevant. Indeed, the HD oil had a blue color due to presence of chamazulene, whereas the volatile concentrate was pale yellow.

Key Word Index:

• Ferula communis
• Apiaceae
• essential oil composition
• supercritical carbon dioxide extract composition