title: Phenolics from monofloral honeys protect human erythrocyte membranes against oxidative damage.
abstract: The aim of the present work was to analyze the phenolic extracts from two monofloral Cuban honeys for their in vitro total antioxidant capacity, phenolic compounds content and free radical scavenging activity. The phenolic extracts, rich in lipophilic compounds, were tested further for their ability to inhibit AAPH-induced oxidative damage (hemolysis, lipid peroxidation and cytosolic depletion of reduced glutathione and decrease of superoxide dismutase activity) in erythrocytes. Results indicate an important total antioxidant capacity measured by TEAC and ORAC assays, as well as a relevant radical scavenging activity performed by EPR. Moreover, 13 phenolic compounds were identified using HPLC-LC/MS with quercetin as the most abundant flavonoid. The results also show that both extracts were able to inhibit erythrocytes oxidative damage, and that this may likely be due to their incorporation into cell membranes and their ability to cross it and reach the cytosol. In fact, flavonoid uptake by erythrocytes was further confirmed by testing quercetin, which efficiently incorporated into erythrocytes. Overall, this study indicates that honey contains relevant antioxidant compounds responsible, at least in part, for its biological activity and that uptake of its flavonoids may provide defense and promote cell functions in erythrocytes.
authors.affiliation: Dipartimento di Science Cliniche, Facoltà di Medicina, Università Politecnica delle Marche, Italy.
authors.forename: José M
authors.initials: JM
authors.lastname: Alvarez-Suarez
authors.forename: Francesca
authors.initials: F
authors.lastname: Giampieri
authors.forename: Ana M
authors.initials: AM
authors.lastname: González-Paramás
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Damiani
authors.forename: Paola
authors.initials: P
authors.lastname: Astolfi
authors.forename: Gregorio
authors.initials: G
authors.lastname: Martinez-Sanchez
authors.forename: Stefano
authors.initials: S
authors.lastname: Bompadre
authors.forename: José L
authors.initials: JL
authors.lastname: Quiles
authors.forename: Celestino
authors.initials: C
authors.lastname: Santos-Buelga
authors.forename: Maurizio
authors.initials: M
authors.lastname: Battino
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004578:Electron Spin Resonance Spectroscopy; D004910:Erythrocyte Membrane / Q000187:drug effects*; D016166:Free Radical Scavengers / Q000494:pharmacology; D006722:Honey; D006801:Humans; D018384:Oxidative Stress / Q000187:drug effects*; D010636:Phenols / Q000494:pharmacology*; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D016166:Free Radical Scavengers; D010636:Phenols