title: Towards green analysis of virgin olive oil phenolic compounds: Extraction by a natural deep eutectic solvent and direct spectrophotometric detection.
abstract: The determination of phenolic compounds in extra virgin olive oils (EVOO) by means of rapid, low-cost, environment-free methods would be a desirable achievement. A natural deep eutectic solvent (DES) based on glucose and lactic acid was considered as extraction solvent for phenolic compounds in EVOO. DESs are green solvents characterized by high availability, biodegradability, safety, and low cost. The spectrophotometric characteristics of DES extracts of 65 EVOO samples were related to the total phenolic content of the oils, assessed by methanol-water extraction coupled to the Folin-Ciocalteu assay. A regression model (ncalibration=45, nvalidation=20), including the absorbance at two wavelengths (257, 324nm), was obtained, with an adjusted R(2)=0.762. Therefore the DES could provide a promising and viable approach for a green screening method of phenolic compounds in EVOO, by means of simple spectrophotometric measurements of extracts, even for on-field analysis (for example in olive mills).
authors.affiliation: University of Bari, Department of Soil, Plant and Food Sciences, Via Amendola 165/a, I-70126 Bari, Italy. Electronic address: vito.paradiso@uniba.it.
authors.forename: Vito Michele
authors.initials: VM
authors.lastname: Paradiso
authors.affiliation: University of Bari, Department of Soil, Plant and Food Sciences, Via Amendola 165/a, I-70126 Bari, Italy. Electronic address: antonia.clemente@uniba.it.
authors.forename: Antonia
authors.initials: A
authors.lastname: Clemente
authors.affiliation: University of Bari, Department of Soil, Plant and Food Sciences, Via Amendola 165/a, I-70126 Bari, Italy. Electronic address: carmine.summo@uniba.it.
authors.forename: Carmine
authors.initials: C
authors.lastname: Summo
authors.affiliation: University of Bari, Department of Soil, Plant and Food Sciences, Via Amendola 165/a, I-70126 Bari, Italy. Electronic address: antonella.pasqualone@uniba.it.
authors.forename: Antonella
authors.initials: A
authors.lastname: Pasqualone
authors.affiliation: University of Bari, Department of Soil, Plant and Food Sciences, Via Amendola 165/a, I-70126 Bari, Italy. Electronic address: francesco.caponio@uniba.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Caponio
mesh_terms: D000069463:Olive Oil / Q000737:chemistry*; D010636:Phenols / Q000032:analysis*; D010936:Plant Extracts; D012997:Solvents; D013053:Spectrophotometry / Q000379:methods*
chemical_list: D000069463:Olive Oil; D010636:Phenols; D010936:Plant Extracts; D012997:Solvents; C011471:folin
keywords: Deep eutectic solvents; Extra virgin olive oil; Folin-Ciocalteu assay; Phenolic compounds; UV spectra