Research Article
Touaibia Meriem, Khaldi Sou
Abstract
The aim of this work is to evaluate the in vivo acute toxicity and the in vitro antioxidant effect of the ethanolic extract obtained from the leafy stems of watercress: Nasturtium officinale R. Br. (Brassicaceae), known locally as "Guernounech" in Algeria, it has been used as a home remedy by the people as a medicinal plant. During the evaluation of acute oral toxicity, we found that the plant extract exerts a stressful effect on mice at different doses, especially at doses of 80 mg/kg and 100 mg/kg, some clinical signs were recorded within eight hours after gavage: strong agitation followed by immobility, several deaths were observed after 72 hours. Thus, N. officinale extract can be considered as a moderately toxic substance with an LD50 included in the range of 50-500 mg/kg body weight. The antioxidative effect is evaluated in vitro by the 1,1-diphenyl-2-picrylhydrazyl (DPPH*) radical scavenging test and the value of the inhibitory concentration IC50 is determined. The results showed that the extract of N. officinale at the concentration of 10 mg/ml, has a low reducing power (I%=3.396%, IC50=11.60 mg/ml) compared to the positive control (ascorbic acid) which showed a high percentage reduction of 92.62% (IC50=0.89 mg/ml), but it increases interestingly at the dose of 100 mg/ml (I%=60.38%).