title: Identification and quantification of phytochemicals in nutraceutical products from green tea by UHPLC-Orbitrap-MS.
abstract: A method has been developed and validated for the simultaneous detection and quantification of phytochemicals in nutraceutical products obtained from green tea. For that purpose, ultra-high performance liquid chromatography coupled to single-stage Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap-MS) has been used. A database containing 37 compounds has been used for the detection and identification of the target compounds. The developed methodology was based on solid-liquid extraction, using a mixture of methanol:H2O (80:20, v/v, pH 4), followed by dilution (10 times) with a mixture of ammonium acetate:methanol (50:50, v/v). Chromatographic conditions were optimised and full scan accurate mass data acquisition using electrospray ionisation in positive and negative ion mode was used. Moreover, all-ion fragmentation mode was used to get information of fragment ions, and they were used for identification purposes. The developed method was validated, obtaining repeatability (intra-day) and inter-day precision values (expressed as relative standard deviation, RSD) lower than 16% and 20%, respectively. Lower limits were also evaluated and limits of detection (LODs) ranged from 1 to 50 μg L(-1), while limits of quantification (LOQs) ranged from 2 to 150 μg L(-1). Recovery was performed at five levels and it ranged from 70% to 109%. Finally, this method was used to evaluate the phytochemical content in 10 samples (tablets or capsules), showing concentrations of (+)-catechin, (-)-epicatechin, gallic acid, (-)-gallocatechin and quercetin-3-O-rutinoside, ranging from 258 (C6) to 10,729 (C6) mg kg(-1).
authors.affiliation: Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: López-Gutiérrez
authors.affiliation: Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain.
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero-González
authors.affiliation: Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Plaza-Bolaños
authors.affiliation: Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Martínez Vidal
authors.affiliation: Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain. Electronic address: agarrido@ual.es.
authors.forename: Antonia
authors.initials: A
authors.lastname: Garrido Frenich
mesh_terms: D002392:Catechin / Q000031:analogs & derivatives / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D019587:Dietary Supplements / Q000032:analysis*; D005707:Gallic Acid / Q000032:analysis; D005960:Glucosides; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000379:methods*; D064209:Phytochemicals / Q000032:analysis*; D011794:Quercetin / Q000031:analogs & derivatives; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization; D013662:Tea / Q000737:chemistry*
chemical_list: D005960:Glucosides; D064209:Phytochemicals; D013662:Tea; D005707:Gallic Acid; D002392:Catechin; D011794:Quercetin; C057580:gallocatechol
keywords: Green tea; Nutraceutical; Phytochemicals; Polyphenol; UHPLC–Orbitrap