Vol. 11, Special Issue 4 (2022)

Author(s):
Raghupathi CH, Vijaya Kumar A, Sujatha Singh, Shashi Kumar M, Shirisha A, Krishnaiah N and Pradeep Kumar A

Abstract:
Nowadays plant-mediated green synthesis of nanoparticles has been increasingly gaining popularity due to its eco-friendly nature and cost-effectiveness. In this present study, synthesis of silver nanoparticles was done using leaf extracts of Azadirachta indica and Ocimum sanctum when added with 1mM silver nitrate solution at different conditions. For synthesizing silver nanoparticles, the plant leaf extracts act as both reducing as well as capping agents due to the presence of flavonoids and terpenoids. Various techniques were used to characterize synthesized silver nanoparticles such as UV-Visible spectrophotometer, Zeta-potential method, and Size distribution by intensity. The absorption spectrum of the silver nano solution prepared by using Azadirachta indica and Ocimum sanctum leaf extracts showed a surface plasmon absorption band with a maximum of 430 nm and 420 nm respectively. The zeta value of silver nanoparticles synthesized from Azadirachta indica and Ocimum sanctum leaf extract was -8.87 mV and -12.3 mV, size of distribution intensity was 112.3 nm and 156.9 nm respectively. In this study, the silver nanoparticle's antimicrobial activity was compared both on isolates and pure culture of Escherichia coli using agar well diffusion method and also compared the antimicrobial resistance of antibiotics on isolates and pure culture of Escherichia coli. Results confirmed this green synthesis protocol as simple, rapid, eco-friendly, non-toxic, and an alternative conventional physical and chemical methods and showed better antimicrobial activity to Escherichia coli.