Antimicrobial Activity of Anogeissus leiocarpus (DC.) Guill. & Perr. and Prosopis africana (Guill., Perrott, & Rich.) (Taub.) Plant Extracts Against Enteric Bacteria

Abstract

The rise of antibiotic-resistant enteric bacteria poses a significant threat to public health, necessitating the search for alternative  antimicrobial agents. Traditional medicinal plants such as Anogeissus leiocarpus and Prosopis africana have long been used in various  cultures for their health benefits, including antimicrobial properties. This study aimed to investigate the antimicrobial activity and qualitative phytochemical composition of crude extracts from A. leiocarpus and P. africana against selected enteric bacteria. The  phytochemical screening revealed the presence of secondary metabolites including saponins, flavonoids, tannins, alkaloids, and cardiac  glycosides in both plants. The aqueous extracts had more abundant secondary metabolites than the methanolic extracts. Antimicrobial  testing showed that increasing the concentration of the extracts enhanced their antibacterial effectiveness, with the aqueous extracts  displaying higher activity than methanolic ones. The test organisms, including E. coli, K. pneumoniae, P. mirabilis, S. enterica, and Shigella  spp., exhibited varying degrees of susceptibility, with a higher sensitivity observed for the aqueous extracts. The minimum  inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts were found to be ≥20 mg/mL for both  aqueous and methanolic fractions. The findings support the traditional use of A. leiocarpus and P. africana in treating bacterial infections,  showcasing their potential as alternative therapeutic agents due to their rich bioactive compounds and significant  antibacterial properties. Further research is recommended to explore the mechanisms of action, pharmacokinetics, and safety profiles of  these extracts for pharmaceutical applications.