title: Quantification of isoflavones in coffee by using solid phase extraction (SPE) and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).
abstract: A new method for extracting isoflavones from espresso coffee (EC) was coupled with high-performance liquid chromatography-tandem mass spectrometry (MS/MS) for the first time to analyse five isoflavones, which included both a glycosilated form, genistin and the aglycons daidzein, genistein, formononetin and biochanin A. Isoflavones were extracted from coffee samples using methanol, stored in a freezer overnight to precipitate proteic or lipidic residues and purified on SPE C18 cartridges before high-performance liquid chromatography-MS/MS analysis. The recovery percentages obtained by spiking the matrix at concentrations of 10 and 100 µg l(-1) with a standard mixture of isoflavones were in the range of 70 to 104%. The limits of detection and limits of quantification were in the range of 0.015-0.3 µg l(-1) and 0.05-1 µg l(-1) , respectively. Once validated, the method was used to analyze the concentrations of isoflavones in six ECs and ten ground coffee samples. Only formononetin and biochanin A were found, and their respective concentrations ranged from 0.36 to 0.41 µg l(-1) and from 0.58 to 3.26 µg l(-1) in ECs and from 0.36 to 4.27 µg kg(-1) and from 0.71 to 3.95 µg kg(-1) in ground coffees. This method confirms the high specificity and selectivity of MS/MS systems for detecting bioactives in complex matrices such as coffee.Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: School of Pharmacy, University of Camerino, Via Sant'Agostino 1, 62032, Camerino, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Caprioli
authors.affiliation: Illycaffè SpA, R & D, via Flavia 110, Trieste, I-34147, Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Navarini
authors.affiliation: School of Pharmacy, University of Camerino, Via Sant'Agostino 1, 62032, Camerino, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Cortese
authors.affiliation: School of Pharmacy, University of Camerino, Via Sant'Agostino 1, 62032, Camerino, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Ricciutelli
authors.affiliation: School of Pharmacy, University of Camerino, Via Sant'Agostino 1, 62032, Camerino, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Torregiani
authors.affiliation: School of Pharmacy, University of Camerino, Via Sant'Agostino 1, 62032, Camerino, Italy.
authors.forename: Sauro
authors.initials: S
authors.lastname: Vittori
authors.affiliation: School of Pharmacy, University of Camerino, Via Sant'Agostino 1, 62032, Camerino, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Sagratini
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003069:Coffee / Q000737:chemistry*; D007529:Isoflavones / Q000032:analysis*; D057230:Limit of Detection; D016014:Linear Models; D015203:Reproducibility of Results; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D003069:Coffee; D007529:Isoflavones
keywords: HPLC-MS/MS; SPE; bioactives; coffee; isoflavones