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.
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.
Marie E
ME
Lucchesi
Farid
F
Chemat
Jacqueline
J
Smadja
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