On the origin of the antioxidant potential of selected wines: combined HPLC, QSAR, and DFT study

Abstract

The phenolic compounds, which are rich in red wine, have gained considerable attention due to their antioxidant potential. Selected Serbian wines were analyzed for their antioxidant activity by DPPH test and the total content of phenolic compounds was determined by employing the Folin–Ciocalteu colorimetric method. The major polyphenols were determined by HPLC. The antioxidant activity was correlated with the amount of specific polyphenols (gallic acid, caffeic acid, catechin, epicatechin, myricetin, and kaempferol) by quantitative structure–activity relationship. The origin of the antioxidant potential of wines was discussed based on the individual activity of identified polyphenols and theoretical calculations (at APFD/6-311++G(d,p) level of theory). The thermodynamic parameters of free radical scavenging activity and reactivity towards DPPH·, HO·, and HOO· were explained with special emphasis on the effect of structure and intramolecular interactions in polyphenols. Based on the presented data, the positive effects of selected Serbian wines on humane health and biologically relevant free radicals are concluded.