Study of the Antioxidant Activity of Two Parts (Leaves and Roots) of a Methanolic Extract of Urtica dioica L from the Wilaya of Sidi Bel Abbes by In-Vitro Test

The aim of our work is to evaluate the antioxidant activity of two parts (leaves and roots) of a methanolic extract of Urtica dioica L. The study of the chemical composition revealed that the leaf extract is richer in polyphenols, flavonoids and tannins than the root extract. The evaluation of the antioxidant effect showed that the inhibition reached its maximum at the highest concentration (initial DPPH concentration = 5000 μg/ml) equal to 89.25 ± 0.0022% for ascorbic acid against 67.17 ± 0.0013% (p<0.05) for the methanolic extracts of the leaves and 17.36 ± 0.0040% (p<0.001) of the roots. The methanolic extract of the leaves has a strong scavenging power of the ABTS˙+ radical with an IC50 equal to 6.59 ± 0.0060 μg/ml, equal (p> 0, 05) to that of ascorbic acid (4.67± 0.0044 μg/ml) and pyrogallol (IC50= 548.7 ± 0.084 μg/ml), with an IC50 of 481.2 ± 0.34 μg/ml for roots, against the latter. Keywords: Urtica dioica L., antioxidant activity, a, leaves, roots