Ouandaogo, H. S.; Diallo, S.; Odari, E.; Kinyua, J.

Using plants in the biological production of silver nanoparticles (AgNPs) is becoming increasingly important as a practical and environmentally benign method. In the current work, silver nanoparticles were made utilizing the significant Ocimum kilimandscharicum, and their potential to combat certain bacteria was discussed. Both aqueous and methanol plant extracts were used for reducing silver nitrate at different time intervals (30 to 150 minutes) and pH (2 to 11). The UV-visible absorption spectrum recorded for both methanol and aqueous extracts revealed successful synthesis of AgNPs. The antimicrobial activity of the AgNPs was evaluated against Escherichia coli ATCC 25922, Salmonella choleraesuius ATCC 10708, and Staphylococcus aureus ATCC 25923. 50mg/ml was the concentration of the extracts tested. The best zone of inhibition was recorded for the methanol and aqueous-mediated AgNPs, ranging from 12{+/-}1 to 16{+/-}1mm. The methanol and aqueous extract silver nanoparticles had the same Minimum Inhibitory Concentration (6.25{+/-}0.00 mg/ml), whereas the Minimum Bactericidal Concentrations were 12.5{+/-}0.00 and 25{+/-}0.00 mg/ml, respectively. The highest inhibition zone of 16{+/-}1 mm was observed against Salmonella choleraesuius with 50{+/-}0.00 mg/ml aqueous silver nanoparticles. The results show that the silver nanoparticles made with Ocimum kilimandscharicum have potent antibacterial action against those microorganisms.