Evaluation of Antioxidant Activity of Aqueous and Ethanolic Extracts of Stem Bark of Xylopia villosa Chipp (Annonaceae)

This study aims to evaluate antioxidant activity of aqueous and ethanolic extracts of Xylopia villosa stem bark. The quantitative study of polyphenols showed that ethanolic extract (75.00 ± 3.82 g/L EqAG) contains more than the aqueous extract (55.83 ± 1.67 g/L EqAG). It is the same for the quantitative analysis of total flavonoids where ethanolic extract (135.00 ± 1.44 g/L EqQ) contains more than the aqueous extract (115.00 ± 6.61 g/L EqQ). The antioxidant activity in vitro showed that the extracts neutralize DPPH and ABTS + ° with enhanced activity of the ethanolic extract. The ethanolic and aqueous extracts of Xylopia villosa causing 50% inhibition (IC50) of the DPPH radical gave concentrations of 10.50 ± 0.24 and 24.50 ± 0.18 mcg / ml respectively for ethanol extract and aqueous extract. On the reduction of radical ABTS + ° , aqueous extract caused a reduction of the radical cation ABTS + 7.82 ± 0.17 micromol TE / L while the ethanol extract reduced by 10.52 ± 0.27 micromol TE / L. Evaluation of antioxidant activity in vivo of xylopia villosa revealed that this is the ethanol extract (9.17 ± 0.48 mmol / L TBA-MDA) which offset the concentration of TBA-MDA adduct more than the aqueous extract (22.67 ± 0.33 mmol / L TBA-MDA). Concerning the total antioxidant activity, ethanolic extract reduced iron III to Iron II more than aqueous extract. After this study, it appears that the ethanolic extract has better antioxidant activity in vitro and in vivo that the aqueous extract.