EVALUATION OF THE ANTIOXIDANT ACTIVITY In vitro AND Ex vivo OF ALMONDS OF Mangifera indica (Anacardiaceae)

Our work consisted in evaluating in vitro the antioxidant activity of methanolic extracts of almonds of 11 varieties of Mangifera indica using the spectrophotometric method with 2,2-diphenyl-1-picrylhydrazyl (DPPH). This work also focused on an ex vivo study of the antioxidant activity of these extracts in mice. The antioxidant effect of the extracts was determined through their anti-inflammatory activity in the respiratory tracts. The anti-inflammatory activity was assessed by counting the total number of cells in the broncho-alveolar lavage (BAL) liquid after a pre-treatment with methanolic extracts. The in vitro results showed an oxidative activity inhibition percentage greater than 94% for all varieties. IC50was determined for three varieties of mangoes, Bu Sew, Kengston and Coagshall, and gave respectively 0.72 mg/ml, 0.48 mg/ml and 0.44 mg/ml. The ascorbic acid chosen as control gave an IC50 equal to 0.147 mg/ml or 0.83 mM. The ex vivo evaluation in mice was performed using the Amelia variety. It was determined by nasal injections of bacterial lipopolysaccharide (LPS) of Escherichia coli that cause inflammation of the respiratory tracts as proven by a high cellularity of 171x104 cells/ml. Mice in groups 4 and 5 were treated respectively with 71.68 mg/ml and 95 mg/ml of extracts and received nasal injections of LPS. These mice showed respectively low cellularities of 71x104cells/ml and 50x104 cells/ml in contrast to the positive control group (171x104 cells/ml). These results show an important anti-inflammatory activity suggesting in turn a significant antioxidant activity of methanolic extracts of Mangifera indica almonds.