Antimicrobial Activity of Bidens pilosa Leaves Extracts Against Staphylococcus aureus and Escherichia coli

Resistance against synthetic antimicrobial agents is one of the major global public health challenges that compel scientists to search for alternatives including those of plants origin. Staphylococcus aureus and Escherichia coli are bacteria responsible for a variety of infections and diseases that causes significant morbidity and mortality in humans and animals. E. coli is widely distributed in nature and commonly found in lower gastro intestinal tracts of most warm-blooded animals associated with urinary tract infections and enterocolitis in humans and colibacillosis in poultry. This study was carried out to investigate antimicrobial activity of methanolic leaf extracts of Bidens pilosa against S. aureus and E. coli. Agar well diffusion method was used to assess antimicrobial activity of the leaf extracts at 20%, 50% and 70% concentrations respectively based on measured zone of inhibition. The leaf extracts of Bidens pilosa produced significant zone of inhibition indicating its antimicrobial activity against E. coli and S. aureus. The antimicrobial activity was demonstrated in all concentrations however, the highest zone of inhibition (18.5mm and 32mm) for E. coli and S. aureus respectively was at 70% concentration. The results shows that Bidens pilosa leaf extracts have antimicrobial activity against the tested bacteria and have the potential for further development including identification of active components that can be tested for treatment of E. coli and S. aureus associated conditions.