COMPLEXATION REACTIONS IN BINARY COMPOSITIONS OF NATURAL CARBOXYL-CONTAINING PHENOLS WITH GALACTOSE

Using NMR and UV-visible spectroscopy, it was found that in hydrochloric acid buffer with pH = 2 at T = 298±2 K in binary compositions of natural carboxyl-containing phenols (hydroxybenzoic and hydroxycinnamic acids) with galactose hydrogen-bonded complexes are formed in the ratio (1:1). The values of stability constants obtained by the Beneshi-Hildebrand method indicate a shift in the equilibrium position toward the formation of associates. The formed hydrogen-bonded complex reacts with hydrazyl radical faster than phenolic antioxidant in individual form, which leads to the appearance of antiradical synergistic effects in phenolic-galactose compositions. Maximum superadditivity effects (> 70%) were exhibited by mixtures of galactose with synapic, gentisic and ferulic acids at a ratio of 70:30% with a total concentration of the substances of 8∙10-5 mol∙l-1.