A comparative study of phytochemical profile and antioxidant activity of Sahelian plants used in the treatment of infectious diseases in northern part of Burkina Faso: Acacia seyal Delile and Acacia tortilis (Forssk.) Hayne subsp. raddiana (Savi)

Acacia seyal and Acacia tortilis are used in the treatment of infectious diseases in traditional medicine by population in Northern Burkina Faso. Phytochemical screening by tube test and on HPTLC plates showed the presence of important chemical compounds in these plants. Determination of total phenolic content using method of Folin-Ciocalteu Reagent (FCR) and antioxidant activity by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) test, showed that this biological activity is related to phenolic content. The trunk bark of A. tortilis had an important antioxidant activity with IC50 value of 0.01±0.01 µg/mL due to its highest content (p<0.05) of total phenolic compounds (383.19±0.07 mg GAE/g), of condensed tannins (18.21±0.04%) and flavonoids (66.09±0.06 mg QE/g). This antiradical activity was comparable to that of Trolox used as reference. Radical scavenging activity of leaves of A. seyal was also significant with IC50 value of 0.02±0.01 µg/mL. Its total phenolic compounds, condensed tannins and flavonoids were estimated at 371.43±0.09 mg GAE/g, 14.24±0.00% and 52.72±0.10 mg QE/g, respectively. This study shows that local plants adapted to drought could make an interesting source of molecules with antioxidant property in the prevention and the treatment of infectious diseases. Key words: Sahel plants, infectious diseases, phenolic compounds, radical scavenging.