The synthesis of metal nanoparticles using biological systems is an expanding research area due to the potential application in nano medicine. Extracellular biosynthesis of silver nanoparticles was carried out by using Ocimum americanum L. leaf extract for the reduction of aqueous silver ions in short period. In view of the importance of silver nanoparticles, the present work reports the synthesis, characterization and investigation of the antibacterial activity of silver nanoparticles from Ocimum americanum using AgNO3. The antimicrobial property of silver nanoparticles was analyzed by measuring the zone of inhibition against E.coli, pseudomonas, streptococci bacteria. The silver nanoparticles formation was identified immediately by the colour change and further confirmed with the help of SEM, EDAX, FTIR, UV-Vis spectroscopy. This paper demonstrates a single step green synthesis that the reaction of aqueous silver ions with plant extract resulted in extracellular formation of silver nanoparticles which further harvested by simple heat drying evaporation. The results indicate that the silver nanoparticles may have an important advantage over conventional antibiotics.
