BIOSYNTHESIS OF SILVER NANOPARTICLES IN LAGERSTROEMIA SPECIOSA (L.) PERS AND THEIR ANTIMICROBIAL ACTIVITIES

Objective: To synthesize silver nanoparticles (AgNPs) using the leaf extract of Lagerstroemia speciosa and to determine their antimicrobial activity. Methods: AgNPs were synthesized by mixing the plant leaf extract with AgNo3 solution and incubated in the dark condition. Results: In the present study, the synthesis of AgNPs was achieved by using the aqueous leaf extract of L. speciosa (L.) Pers in 0.5 mM AgNo3 solution. The synthesized AgNPs was characterized by using UV- visible spectrophotometer, Fourier Transform Infrared (FT- IR) spectroscopy and Field Emission Scanning Electron Microscopic (FESEM). The technique is initially to synthesize AgNPs the reaction mixture was incubated separately at different temperatures at 30˚c, 40˚c, 50˚c, 60˚c, 70˚c and 80˚C. Absorbance spectrum was measured in UV-visible spectrophotometer. The samples were incubated at 70oC and 80oC showed peak absorbance at 435 nm and 432 nm respectively. Antimicrobial activity of synthesized AgNPs was carried out using Streptomycin and Ketoconazole as control for bacteria and fungi respectively. The results show that the growth inhibitory zone of 0.6 - 2.0 cm for bacterial strains (Staphylococcus aureus, Proteus vulgaris, Pseudomonas aureginosa and Klebsiella sp.) and 0.7 cm – 1.8 cm for fungal strains (Aspergillus flavus, Aspergillus niger, Curvularia sp. and Cladosporium sp.). The biosynthesis of AgNPs from L. speciosa appears to be Eco-friendly method in nature. Conclusion: To summarize, in this study we have successfully synthesized AgNPs using medicinally important L. speciosa as potential reducing and stabilizing agent. The biosynthesis of silver nanoparticles had several advantages in pharmaceutical applications as well as large scale commercial production.