Assessment of Antimicrobial Activities of Some Selected Medicinal Plants Used in the Treatment of Skin and Wound Infections in Bauchi Town, Bauchi State Nigeria

Abstract

Aims: This study aimed to capture the medicinal plants used locally to treat skin and wound infection, and to investigate the antimicrobial activity of the ethanol, ethyl acetate, and aqueous extracts of Azadiracta indica, Mitracarpus hirtus, Calotropis procera, and Commiphora africana against bacterial and fungal pathogens causing skin and wound infections. Study Design: This was a cross-sectional analytical study, conducted in Bauchi town from January to April 2024 at the Department of Medical Microbiology, Abubakar Tafawa Balewa University. Methodology: A semi-structured questionnaire was used to gather information on the use of medicinal plants in treating skin and wound diseases. Twelve leaves extracts from Azadirachta indica, Mitracarpus hirtus, Calotropis procera, and Commiphora africana were screened for their antimicrobial activity against four bacterial and one fungal pathogen; Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa klebsiella pneumonia, Escherichia coli and Trichophyton rubrum using Agar Disc Diffusion Assay. Minimum Inhibitory Concentrations (MIC) was performed using micro broth dilution assay. Results: A total of 94 respondents used 28 medicinal plants for skin and wound disease management, including leaf paste, infusion, root powder, dried powdered leaves, and oral decoction. The most common plants used were Azadirachta indica, Mitracarpus hirtus, Calotropis procera, and Commiphora africana, used to treat eczema, ringworm, skin rashes, and burnt wounds. All of the plant extracts were effective in inhibiting bacterial and fungal growth at variable concentrations, with Mitracarpus hirtus being the most effective. Mitracarpus hirtus showed the greatest zone of inhibition (ZOI >20 mm) against Staphyloccus aureus and Trichophyton rubrum, followed by Calotropis procera, which had moderate activity on the test isolates with a mean ZOI >11mm. Azadirachta indica and Commiphora africana exhibited mild to poor action on the majority of the isolates. For each plant extract, the MIC values differed according to the bacterial species. Mitracarpus hirtus had the lowest MIC against Staphyloccus aureus at 0.325 mg/mL, as did Calotropis procera against Klebsiella  pneumoniae. Conclusion: The study discovered that many medicinal plants had promising antibacterial activities against the tested isolates, but more research is required to identify and purify active components for safe use.