title: Identification and quantification of soluble free, soluble conjugated, and insoluble bound phenolic acids in durum wheat (Triticum turgidum L. var. durum) and derived products by RP-HPLC on a semimicro separation scale.
abstract: A straightforward semimicro separation scale RP-HPLC method was developed for the identification and quantification of phenolic acids (PAs) occurring as soluble free, soluble conjugated, and insoluble bound compounds, which were independently extracted from wholemeal of durum wheat and from its derived products coarse bran, semolina, and dried pasta. A narrow bore column and a semimicro photodiode array detector (PDA) cell, in conjunction with a single quadrupole mass spectrometer, equipped with an electrospray ionization source (ESI-MS), were employed. The method was validated in terms of linearity of calibration graphs, limits of detection, limits of quantification, repeatability, and accuracy, which was evaluated by a recovery study. In each sample (wholemeal, coarse bran, semolina, and dried pasta), the total amounts of the three different forms of PAs were in the order bound > conjugated > free, with bound PAs accounting for 61.0-83.6% of the total PAs. Ferulic acid was the most abundant PA in both soluble free and insoluble bound forms, whereas sinapic acid predominated in the conjugated ones. The highest PA content, calculated as the sum of total PAs quantified in the three forms, was found in coarse bran, followed by wholemeal, semolina, and dried pasta.
authors.affiliation: Istituto di Metodologie Chimiche, Consiglio Nazionale delle Ricerche , Area della Ricerca di Roma 1, via Salaria Km 29,300, 00016 Monterotondo Stazione (Roma), Italy.
authors.forename: Isabella
authors.initials: I
authors.lastname: Nicoletti
authors.forename: Daniela
authors.initials: D
authors.lastname: Martini
authors.forename: Antonella
authors.initials: A
authors.lastname: De Rossi
authors.forename: Federica
authors.initials: F
authors.lastname: Taddei
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: D'Egidio
authors.forename: Danilo
authors.initials: D
authors.lastname: Corradini
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D056148:Chromatography, Reverse-Phase / Q000295:instrumentation / Q000379:methods; D005433:Flour / Q000032:analysis; D062385:Hydroxybenzoates / Q000737:chemistry*; D013058:Mass Spectrometry; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry*; D014908:Triticum / Q000737:chemistry*
chemical_list: D062385:Hydroxybenzoates; D010936:Plant Extracts; C017616:phenolic acid