RESUMO
Antioxidant activity of the ethanolic extract and fractions from the stem bark of T. catigua was investigated. IC50 (for DPPH scavenging) by T. catigua varied from 9.17 ± 0.63 to 76.42 ± 5.87 mg mL⻹ and total phenolic content varied from 345.63 ± 41.08 to 601.27 ± 42.59 mg GAE g⻹ of dry extract. Fe²âº-induced lipid peroxidation was significantly reduced by the ethanolic extract and fractions. Mitochondrial Ca²âº-induced dichlorofluorescein oxidation was significantly reduced by the ethanolic extract in a concentration-dependent manner. Ethanolic extract reduced mitochondrial Δψm only at high concentrations (40-100 mg mL⻹), which indicates that its toxicity does not overlap with its antioxidant effects. Results suggest involvement of antioxidant activities of T. catigua in its pharmacological properties.