QSAR study of antioxidant activity of wine polyphenols.

Quantitative structure activity relationships (QSAR) were obtained describing the antioxidant activity of the main pharmacologically active polyphenols of wine, using molecular properties and descriptors derived from the 2D and 3D representations of molecules. The best models for the prediction of the ability to scavenge the ABTS radical cation were obtained by polynomial regression analysis using zero-order connectivity index and molar refractivity. Statistically, significant models for lipid peroxidation inhibiting effects of flavonoids were obtained by polynomial and multiple regression using lipophilicity, Balaban index, Balaban-type index and 3D GETAWAY descriptor. The 3D descriptors possess the ability for discrimination of stereoisomers, like catechin and epicatechin. We demonstrated that a size and shape of molecules, as well as steric properties, play an important role in the antioxidant activity of polyphenols.