Distinct Effects of Resveratrol, ε-Viniferin and Vaticanol C on Activation of PPARs, Radical Scavenging Activity and SIRT1 Activation. (A) Activation of PPARα, β/δ, and γ was evaluated by cell-based transfection assays at a dose of 10 μM. Trolox, a standard antioxidant, was used as control. (B) Radical scavenging activity was evaluated by the DPPH method. Each result is expressed as the equivalent per mole of trolox from the percentage decrease with respect to the negative control values. (C) SIRT1 activation in vitro was evaluated by the Fluor de Lys fluorescence assay. DMSO was used as a negative control and also as a solvent for resveratrol and its derivatives to a final concentration of 100 μM in the assay buffer.