Solvent-free microwave extraction : an innovative tool for rapid extraction of essential oil from aromatic herbs and spices.
A relatively simple apparatus is described for extracting essential oils from aromatic plant material by atmospheric solvent-free microwave extraction (SFME) without the addition of any solvent or water. Isolation and concentration of volatile compounds were performed by a single stage. The product solutions of volatile compounds were directly analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The essential oils fiom aromatic herbs (basil, crispate mint, thyme) and spices (ajowan, cumin, star anise) extracted by SFME for 30 minutes and I hour, were similar to those obtained by conventional hydro-distillation (HD)for (respectively) 4 and 8 hours. Substantially higher amounts of oxygenated compounds and lower amounts of monoterpenes hydrocarbons are present in the essential oils of the aromatic plants extracted by SFME in comparison with HD. Solvent-free microwave extraction is clearly advantageous to conventional distillation in terms of rapidity, efficiency, cleanliness, substantial saving of energy, and is environmentally friendly.
Lucchesi
Marie E
ME
Laboratoire de Chimie des Substances Naturelles et des Sciences des Aliments Faculté des Sciences et Technologies, Université de la Réunion, 15 avenue René Cassin, B.P. 7151, F-97715 Saint Denis messag Cedex 9, La Réunion, France.
Chemat
Farid
F
Smadja
Jacqueline
J
D005591:Chemical Fractionation / Q000379:methods*; D006841:Hydrocarbons, Aromatic / Q000302:isolation & purification* / Q000528:radiation effects; D008872:Microwaves; D010936:Plant Extracts / Q000302:isolation & purification* / Q000528:radiation effects; D010938:Plant Oils / Q000302:isolation & purification* / Q000528:radiation effects; D010946:Plants, Medicinal / Q000737:chemistry* / Q000528:radiation effects; D012997:Solvents; D017365:Spices / Q000032:analysis* / Q000528:radiation effects
D006841:Hydrocarbons, Aromatic; D010936:Plant Extracts; D010938:Plant Oils; D012997:Solvents