Investigation of free seleno-amino acids in extra-virgin olive oil by mixed mode solid phase extraction cleanup and enantioselective hydrophilic interaction liquid chromatography-tandem mass spectrometry. (25th April 2019)

• Record Type: Journal Article
• Authors: Piovesana, Susy; Montone, Carmela Maria; Antonelli, Michela; Cavaliere, Chiara; La Barbera, Giorgia; Canepari, Silvia; Samperi, Roberto; Laganà, Aldo; Capriotti, Anna Laura
• Is Part Of: Food chemistry. Volume 278(2019)
• Page Start: 17
• Page End: 25
• Publication Date: 2019-04-25
• Subjects: Seleno-amino acids -- Total Selenium -- Extra virgin olive oil -- Enantioselective high performance liquid chromatography (eHPLC) -- Mass spectrometry; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2018.11.053
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: New method for very sensitive determination of seleno-amino acids in oil. Enantioselective separation of seleno-amino acids and detection by ESI-MS/MS. Only seleno-methionine was found in 8/32 Italian extra-virgin olive oils. Seleno-methionine concentration correlated with the total Se content in oils. Abstract: An analytical method for determining seleno-methionine (SeMet), methyl-seleno-cysteine and seleno-cystine in extra-virgin olive oil (EVOO) was developed and validated. EVOO sample (15 g) was diluted with hexane, extracted with methanol/water 80:20 ( v/v ), and cleaned up by a reversed phase/strong cation exchange solid phase extraction. Analysis was performed by chiral hydrophilic interaction liquid chromatography-tandem mass spectrometry. Process efficiency ranged between 49 and 97% and trueness between 87 and 126%, with intermediate precision, expressed as standard deviation, lower than 10%. Method detection limits (MDLs) and method quantification limits (MQLs) were lower than 1 μg kg −1 . Thirty-two EVOO samples from different Italian regions were analyzed for both total Se and single seleno-amino acids determination. Only l -SeMet was found at level MQL (0.2 μg kg −1 )-1.42 μg kg −1 in ten samples, while total Se was in the range of MDL-9.1 μg kg −1 . Concentration of l -SeMet (5–6% of total Se) and total Se correlated very well to each other (R 2 = 0.995).