Flavonoid-metal cation interactions were studied via antioxidant property evaluation with binary mixtures of 08
flavonoids with 10 metal cations at different concentrations. We have shown in the analysis by DPPH. Radical method, that despite different behaviors of metals, antioxidant capacity is reduced for some mixtures in methanolic solution, ratio 1:1 of flavonoids: quer-cetin, rutin, luteolin-7-glucoside and eriodictyol with Al3+, Fe2+ and Fe3+ ions. After analysis of influences of concentrations, studied metallic cations were divided in three groups. These cations also lead to an improvement in dosedependent antioxidant capacity of flavonoids, and this more for aglycone compound than for glycosides. These observed interactions could well exist in plant extracts rich in major cations co-extracted and may be assessed in global evaluation of antioxidant or biological properties.

Chelation, Flavonoid, Inorganic cation, Antioxidant capacity