Evaluation of antioxidant activity and quantification of total polyphenols from extracts from leaves and roots of Jatropha chevalieri (Euphorbiaceae)

Abstract

Objective: The objective of this study was to demonstrate the antioxidant capacity and the total polyphenols content of extracts of leaves and roots from Jatropha chevalieri.
Methodology: The antioxidant activity of the crude extracts and their fractions were evaluated by scavenging methods 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azino-bis- (3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) using molecular spectrophotometry. The content of total polyphenols was determined by the universal Folin-Ciocalteu method.
Results: The concentrations of the extracts and fractions allowing to obtain a percentage inhibition of 50% (IC50) are between (0.115±0.002) mg/mL and (1.516±0.065) mg/mL with DPPH. They are between (7.740±0.895) and (72.020±11.028) x10-3 mg/mL with ABTS. Ascorbic acid, used as a control, showed IC50 of (0.0140 ± 0.0002) and (0.920± 0.017) x10-3 mg/mL, respectively for DPPH and ABTS. The total polyphenols content is between (42.67±6.51) and (147.67±21.08) mg EAT/g of extract for the leaves. For the roots, it varies from (22.33±12.10) to (36.33±10.78) mg EAT/g of extract depending on the nature of the extract.
Conclusion: These results describe a strong antioxidant activity of the extracts of leaves and roots of Jatropha chevalieri.