LAUSR

Background Due to improper use of antibiotics, some pathogenic bacteria that cause serious and deadly infections have become resistant to commonly used broad spectrum antibiotics. This antibiotic resistance has become major global healthcare problem. Therefore, there is an urgent need to develop novel antibacterial agents; hence, much attention has been made on medicinal plants such as Artemisia afra. Thus, the current study was aimed to evaluate the antibacterial activity of ethanolic, methanolic and n-hexane extracts of this plant leaf against four multi-antibiotic resistant clinical pathogens. Methods Crude extracts from A.afra leaf were prepared using ethanol, methanol and n-hexane and the antibacterial effect of each extract was tested against Escherichia coli, Streptococcus pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus. In addition, minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were evaluated. Results Among the crude extracts, the highest zone of inhibition (25.33±0.58mm) was recorded against E. coli when methanolic extract was applied. On the other hand, the lowest inhibition was exhibited when n-hexane extract was applied against S.aureus (5.67±1.56 mm). Concerning MIC values of the different extracts, varied results were obtained. MIC value of 6.25mg/mL was recorded when methanolic extract was applied against all clinical pathogens. Moreover, both methanolic and ethanolic extracts showed MBC value of 12.5mg/mL against the four clinical pathogens. However, the methanolic extract gave MBC value of 6.25mg/mL against E. coli. Conclusion From this study, it can be concluded that it is possible to develop and formulate of new, efficacious, less toxic and inexpensive herbal medicine from A.afra leaf extract that act against multi-antibiotic resistant clinical pathogens.