Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires (LAMICODA), Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA), 1 BP 1515 Lomé 1, Université de Lomé, Togo
The objective of this study was to assess the antimicrobial properties of the extracts of two leafy vegetables Amaranthus spinosus and Tridax procumbens traditionally used in the maritime region of Togo for their therapeutic properties. The agar well diffusion and Mueller Hinton broth microdilution methods were used to estimate the antimicrobial potential of the hydroethanolic extracts of the leaves of these plants on six reference strains and nine clinical strains including three multi-resistant and extended-spectrum beta-lactamase (ESBL) producing. Antimicrobial susceptibility tests have shown that these tested extracts variously inhibit the growth of the used strains. The extract of T. procumbens was the most active and inhibited the growth of all strains except Candida albicans 1581 with diameters of inhibition zones varying from 9 to 31 mm. The extract of A. spinosus inhibited the growth of 11 strains out of the 15 with inhibition zones diameters ranging from 7 to 17.5 mm. The minimum inhibitory concentrations varied from 0.39 to 3.12 mg/mL and the total activities from 42.43 to 339.48 mL/g. The extract of T. procumbens, which is very active on the strains used, could be used to search for new active molecules to fight against microbial infections. These results show that the hydroethanolic extracts of the leaves of the two plants have antimicrobial activities and support their traditional use in the treatment of microbial infections.