The effect of flavonoids on the reduction of cupric ions, the copper-driven Fenton reaction and copper-triggered haemolysis. (15th November 2022)

• Record Type: Journal Article
• Authors: Lomozová, Zuzana; Hrubša, Marcel; Conte, Palma Federica; Papastefanaki, Eugenia; Moravcová, Monika; Catapano, Maria Carmen; Proietti Silvestri, Ilaria; Karlíčková, Jana; Kučera, Radim; Macáková, Kateřina; Mladěnka, Přemysl
• Is Part Of: Food chemistry. Volume 394(2022)
• Publication Date: 2022-11-15
• Subjects: OH hydroxyl radical -- 2, 3-DHBA 2, 3-dihydroxybenzoic acid -- 2, 5-DHBA 2, 5-dihydroxybenzoic acid -- BCS disodium bathocuproine disulphonate -- DMSO dimethylsulfoxide -- EDTA ethylenediaminetetraacetic acid -- HA hydroxylamine hydrochloride -- HEPES 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid -- HPLC high-performance liquid chromatography -- LDH lactate dehydrogenase -- ROS reactive oxygen species -- TRIS tris(hydroxymethyl)aminomethane; Flavonoids -- Copper -- Antioxidants -- Reduction -- Fenton reaction -- Hydroxyl radical; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.133461
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: 24 structurally related flavonoids were tested. Most of them were potent copper reductants. Eight flavonoids potentiated copper-based Fenton reaction. Most flavonoids protected erythrocytes against copper-triggered lysis. 5-hydroxyflavone was the only antioxidant compound in both assays. Abstract: Flavonoids are considered beneficial, but they may exhibit pro-oxidative effects likely due to metal reducing properties. For the first time, 24 structurally related flavonoids were compared for copper reduction, and modulation of the copper-triggered Fenton reaction and lysis of erythrocytes. The vast majority of flavonoids reduced cupric ions; their behaviour ranged from progressive gradual reduction through bell-shaped, neutral, to a blockade of spontaneous reduction. Similarly, different behaviours were observed with the Fenton reaction. Flavone was the only flavonoid that potentiated copper-triggered haemolysis (155 ± 81 % at twice the amount of Cu 2+ ), while 18 flavonoids were at least partly protective in some concentrations. Only 5-hydroxyflavone did not reduce Cu 2+ and behaved as an antioxidant in both assays (reduction of 60 ± 10 % and 88 ± 1%, respectively, at an equimolar ratio with Cu 2+ ). In conclusion, relatively subtle structural differences resulted in very different anti/prooxidant behaviour depending on the model.