From the methanolic extract of Quercus ilex leaves a series of acylated flavonol glucosides were identified, among them five new naturally occurring compounds. The constituents, which were all p-coumaroyl glucosides of kaempferol, were characterised either as pure compounds or as inseparable, complicated mixtures of cis and trans isomers. Their complete structure elucidation was done by 2D NMR (COSY, HSQC, HMBC, ROESY) and HPLC-DAD-MS analyses. 2D NMR spectral data allowed the discrimination between different isomers. Quantitative analysis of the methanolic extract of the plant revealed that it is a rich source of acylated flavonoid glucosides (1.22%). Under the experimental conditions chosen HPLC-DADMS analyses showed that cis isomers are less polar than trans isomers and their detailed identification, the first in the literature so far, could serve as a tool for the detailed characterisation of analogous isomers by HPLC-DAD-MS in other complicated plant extracts.

Quercus ilex L. : a rich source of polyacetylated flavonoid glucosides / A.Karioti; A.R.Bilia; H.Skaltsa. - In: FOOD CHEMISTRY. - ISSN 0308-8146. - STAMPA. - 123:(2010), pp. 131-142.

Quercus ilex L. : a rich source of polyacetylated flavonoid glucosides

KARIOTI, ANASTASIA;BILIA, ANNA RITA;
2010

Abstract

From the methanolic extract of Quercus ilex leaves a series of acylated flavonol glucosides were identified, among them five new naturally occurring compounds. The constituents, which were all p-coumaroyl glucosides of kaempferol, were characterised either as pure compounds or as inseparable, complicated mixtures of cis and trans isomers. Their complete structure elucidation was done by 2D NMR (COSY, HSQC, HMBC, ROESY) and HPLC-DAD-MS analyses. 2D NMR spectral data allowed the discrimination between different isomers. Quantitative analysis of the methanolic extract of the plant revealed that it is a rich source of acylated flavonoid glucosides (1.22%). Under the experimental conditions chosen HPLC-DADMS analyses showed that cis isomers are less polar than trans isomers and their detailed identification, the first in the literature so far, could serve as a tool for the detailed characterisation of analogous isomers by HPLC-DAD-MS in other complicated plant extracts.
2010
123
131
142
A.Karioti; A.R.Bilia; H.Skaltsa
File in questo prodotto:
File Dimensione Formato  
Quercus.pdf

Accesso chiuso

Tipologia: Versione finale referata (Postprint, Accepted manuscript)
Licenza: Tutti i diritti riservati
Dimensione 798.96 kB
Formato Adobe PDF
798.96 kB Adobe PDF   Richiedi una copia

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/594260
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 39
  • ???jsp.display-item.citation.isi??? ND
social impact