title: Qualitative and semi-quantitative analysis of phenolics in Eucalyptus globulus leaves by high-performance liquid chromatography coupled with diode array detection and electrospray ionisation mass spectrometry.
abstract: BACKGROUND
  Eucalyptus species are widely cultivated in Mediterranean regions. Moreover, plants of this family have been utilized for medicinal purposes. A number of studies have been devoted to the identification of eucalypt phenolics, all of them have focused on specific families of compounds, and no exhaustive profiling has been reported in leaves of this plant.
  
  
  OBJECTIVE
  To develop methods that allows the identification and quantification of different classes of phenolics in Eucalyptus globulus leaf.
  
  
  METHODS
  Acetonic extract was fractionated by chromatography on a Sephadex LH-20 column using consecutive elution with ethanol, methanol and aqueous acetone (60%). High-performance liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS) were applied to determine the structure of different compounds. Quantities were evaluated from peak areas in the HPLC profile, using external calibration curves.
  
  
  RESULTS
  Fractionation of acetonic extract yielded three fractions: F1, F2 and F3. In total 39 phenolic compounds are detected. Among them: 16 hydrolyzable tannins, 3 terpenyl derivatives, 12 ellagic acid derivatives, 5 flavonols, 2 hydroxybenzoic acids and 1 formylated phloroglucinol. 26 compounds described in this study have not previously detected in leaves of this plant and this is the first report of quercetin 3-O-β-galactoside-6"-O-gallate and cypellogin A and B, in E. globulus plant. Quantitatively, ellagic acid derivatives and sideroxylonal A or B are largely predominant.
  
  
  CONCLUSIONS
  Fractionation of crude extract by chromatography on Sephadex LH-20 was efficient to separate different molecular weight compounds. HPLC-DAD-ESI/MS enabled detection of gallotannin, ellagitannin and flavonol derivatives, in leaves of E. globulus.
authors.affiliation: Faculté des Sciences de la Nature et de la Vie, Laboratoire 3BS, Université A. Mira de Bejaia, Algérie. lilaboulekbachemakhlouf@yahoo.fr
authors.forename: Lila
authors.initials: L
authors.lastname: Boulekbache-Makhlouf
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Meudec
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Mazauric
authors.forename: Khodir
authors.initials: K
authors.lastname: Madani
authors.forename: Véronique
authors.initials: V
authors.lastname: Cheynier
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003911:Dextrans; D005052:Eucalyptus / Q000737:chemistry*; D015394:Molecular Structure; D010636:Phenols / Q000032:analysis* / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry*; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D003911:Dextrans; D010636:Phenols; C025614:sephadex