title: Characterization of volatile compounds of Daucus crinitus Desf. Headspace Solid Phase Microextraction as alternative technique to Hydrodistillation.
abstract: BACKGROUND
  Traditionally, the essential oil of aromatic herbs is obtained using hydrodistillation (HD). Because the emitted volatile fraction plays a fundamental role in a plant's life, various novel techniques have been developed for its extraction from plants. Among these, headspace solid phase microextraction (HS-SPME) can be used to obtain a rapid fingerprint of a plant's headspace. Daucus crinitus Desf. is a wild plant that grows along the west coast of Algeria. Only a single study has dealt with the chemical composition of the aerial part oils of Algerian D. crinitus, in which isochavicol isobutyrate (39.0%), octyl acetate (12.3%), and β-caryophyllene (5.4%) were identified. Using GC-RI and GC-MS analysis, the essential oils and the volatiles extracted from separated organs of D. crinitus Desf. were studied using HS-SPME.
  
  
  RESULTS
  GC-RI and GC-MS analysis identified 72 and 79 components in oils extracted using HD and in the volatile fractions extracted using SPME, respectively. Two types of essential oils were produced by the plant: the root oils had aliphatic compounds as the main component (87.0%-90.1%), and the aerial part oils had phenylpropanoids as the main component (43.1%-88.6%). HS-SPME analysis showed a more precise distribution of compounds in the organs studied: oxygenated aliphatic compounds were well represented in the roots (44.3%-84.0%), hydrocarbon aliphatic compounds were in the leaves and stems (22.2%-87.9%), and phenylpropanoids were in the flowers and umbels (47.9%-64.2%). Moreover, HS-SPME allowed the occurrence of isochavicol (29.6 - 34.7%) as main component in D. crinitus leaves, but it was not detected in the oils, probably because of its solubility in water.
  
  
  CONCLUSIONS
  This study demonstrates that HD and HS-SPME modes could be complimentary extraction techniques in order to obtain the complete characterization of plant volatiles.
authors.affiliation: Université de Corse, UMR CNRS 6134, Laboratoire Chimie des Produits Naturels, Campus Grimaldi, BP 52, 20250 Corte, France. muselli@univ-corse.fr.
authors.forename: Mohammed
authors.initials: M
authors.lastname: El Amine Dib
authors.forename: Nassim
authors.initials: N
authors.lastname: Djabou
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Desjobert
authors.forename: Houcine
authors.initials: H
authors.lastname: Allali
authors.forename: Boufeldja
authors.initials: B
authors.lastname: Tabti
authors.forename: Alain
authors.initials: A
authors.lastname: Muselli
authors.forename: Jean
authors.initials: J
authors.lastname: Costa