Antimicrobial Activity of Selected Medicinal Plants from a Sub-Saharan African Country against Bacterial Pathogens from Post-Operative Wound Infections

BACKGROUND: Globally, the application of medicinal plants in the management of acute and chronic wounds can be considered a common occurrence in most traditional medicine practices. In view of this, many plants in the tropical and subtropical regions have been screened for their wound-healing activities. Consequently, plants having antimicrobial activity against multidrug-resistant (MD-R) pathogens can be considered great assets. Therefore, this study evaluated ethanolic and aqueous extracts of five medicinal plants (Psidium guajava, Myrianthus arboreus, Alchornea cordifolia, Momordica charantia, and Justicia flava) for their antimicrobial activities against MD-R bacterial pathogens isolated from post-operative wounds; Methods: This involved the aqueous and ethanolic extraction of the selected medicinal plants. Preliminary phytochemical constituents of the plants were examined. The agar well diffusion method was then used to determine the antibacterial activity of the leaves against reference strains (Escherichia coli ATCC 25922, Salmonella typhi ATCC 19430, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923, and a Methicillin-Resistant Staphylococcus aureus strain) as well as the MDR clinical isolates (E. coli, P. aeruginosa, S. aureus and CoNS) from the wounds; Results: The preliminary phytochemical analysis of the leaves showed the presence of saponins, phenolics, and reducing sugars in almost all the plants tested. All plant extracts were observed to have some antimicrobial activity against at least one reference strain. For the clinical MDR isolates, A. cordifolia from this study showed highest inhibition to growth of all bacteria used. Activity of J. flava against S. aureus was highest as compared to that of E.coli and P. aeruginosa. Similar observation was made for M. arboreus, P. guajava and M. charantia where the highest activity was observed against S. aureus; Conclusion: This study has mainly shown that P. guajava, M. arboreus, A. cordifolia, M. charantia, and J. flava exhibits antimicrobial activities against MD-R bacterial pathogens isolated from post-operative wounds. Also, these plants has bioactive phytochemical compounds with potential medicinal values for the treatment of numerous infections. Therefore, these plants may be helpful in the management of acute and chronic wounds, especially in traditional medicine practices.