Abstract

OPTIMIZATION OF THE ANTIBACTERIAL ACTIVITY OF TERMINALIA MANTALY H. PERRIER (COMBRETACEAE) ON THE IN VITRO GROWTH OF ESCHERICHIA COLI

Kokora Aya Philomène*, Moroh Jean-Luc Aboyah, Karamoko Detto, Ackah Jacques Auguste Alfred Bognan, Kra Adou Koffi Mathieu and Coulibaly Adama

ABSTRACT

Purpose: The multi-resistance of bacteria to several antibiotics limits treatments, so it is necessary to make a contribution to the fight against antimicrobial resistance. To this end, several preparations of Terminalia mantaly extracts were tested on a susceptible strain and a multidrug-resistant strain of Escherichia coli. Method: Total extracts obtained by maceration, the ethanolic extract (70%) underwent several partitions in three solvent mixtures. The aqueous phase of the partition hexane-water (50/50, v / v) having been identified as the most active of these extracts, was subsequently chromatographed on Sephadex G50 gel. The evaluation of the antibacterial activity of the extracts was carried out by two methods including the diffusion method in agar medium and the dilution method in a liquid medium. Results: The activity of the ethanolic extract (MIC: 312.5 μg /mL on Escherichia coli ATCC 25922 and 1250 μg / mL on multiresistant Escherichia coli) was improved thanks to the hexane-water partition. The aqueous phase of the partition hexane-water obtained for this purpose (MIC: 156.25 μg / mL on Escherichia coli ATCC 25922 and 625 μg / mL on multiresistant Escherichia coli) was chromatographed on Sephadex G50 filtration gel. Of the 22 fractions obtained, fractions F14 and F15 showed the best antibacterial activity (MIC: 19.53 μg / mL on Escherichia coli ATCC 25922, 39.06 μg / mL on multiresistant Escherichia coli). Conclusion: The inhibitory activity of these fractions is bactericidal. The extraction method from the hydroalcoholic extract, followed by the hexane-water partition, then chromatography, allowed the optimization of the antibacterial activity of Terminalia mantaly.

Keywords: Antibacterial activity, antimicrobial resistance, optimization, Terminalia mantaly.