Antioxidant activity of the mangiferin inclusion complex with β-cyclodextrin

The aim of this study was to characterize the complex between mangiferin (MGN) with beta-cyclodextrin (beta-CD) obtained through the co-evaporation method using Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared spectroscopy (FT-IR), as well as to verify the antioxidant activity of this complex by means of radical scavenging activity toward 2,2'-diphenyl-1-picrylhydrazyl radical (RSA-DPPH.), with additional analysis of solvent effects, and Oxygen Radical Antioxidant Capacity-Fluorescein (ORAC-FL) assays. The protective effects of MGN and the MGN:beta-CD complex against peroxyl radical-initiated membrane lipid peroxidation were also evaluated. The analysis of the solvent effects in the DPPH. method demonstrated that at amounts of organic solvents lower than the ratio 50:50 (methanol-water or ethanol-water) there is a drawback, due to the hydrophobic nature of DPPH and should not be used. The antioxidant activity of the MGN:beta-CD complex was higher than in its free form, as seen by both methods. The RSA-DPPH. value was twofold larger for the complex while the ORAC-FL value was fifteenfold larger. Lipid peroxidation assays showed that the MGN:beta-CD complex has a protective effect on the membrane that is as effective as the positive control (Trolox). (C) 2012 Elsevier Ltd. All rights reserved.