Stilbenes in Red Wine: Formation and Biological Potential of Resveratrol and Piceid Dimers

Resveratrol and its glucoside, piceid, are the primary stilbenes present in wine. These compounds are well known for their pharmaceutical properties. However, these compounds can undergo chemical transformations in wines, such as polymerization in the presence of metallic reagents. This study investigates the oxidative coupling of resveratrol and piceid to form dimers, including δ-viniferin and δ-viniferin-diglucoside. These dimers were synthesized using silver acetate. The formation of these stilbenes was monitored in wine model solutions and red wines. The results indicated that resveratrol and piceid underwent transformation during heat treatment, forming their respective dimers. The polymerization of both compounds is temperature-dependent, with higher conversion rates at elevated temperatures. Notably, piceid was more reactive than resveratrol in wine. Finally, the anti-inflammatory effects of these compounds were evaluated on the RAW 264.7 macrophage cell line.