The Inhibitory Action of Several Bioantioxidants and Their Mixtures in a Model Hemoglobin–Hydrogen Peroxide–Luminol Chemiluminescent System

Determination of the antioxidant activities of various biological objects, for example, food, medicinal preparations, beverages, blood plasma, and other human biological fluids, is an important task for biomedical research. Chemiluminescent methods are widely used for this purpose. These methods are sensitive and rapid and make it possible to directly control the kinetics of inhibition of oxidation by an antioxidant. In the present work, a chemiluminescent model was used of free-radical oxidation of luminol, as initiated by a mixture of hemoglobin–hydrogen peroxide in an aqueous medium. The kinetics of the inhibitory effect of eight water-soluble bioantioxidants with different molecular structures and their binary mixtures was studied; the inhibition parameters of luminol oxidation by these antioxidants and their stoichiometric coefficients were determined. Features of the inhibition kinetics for glutathione are revealed. The synergistic and antagonistic effects of antioxidants in the mixtures were evaluated. The independence of chemiluminescence quenching by individual antioxidants was noted for the majority of the studied binary antioxidant mixtures, with more “active” antioxidants inhibiting oxidation earlier than less “active” ones. Mixtures of some antioxidants that strengthened or weakened each other upon interacting, thus exhibiting synergism or antagonism, were an exception.