Green synthesis of silver nanoparticles from aqueous extract of leaves of Azadirachta indica, its phytochemical screening and antibacterial activity

Silver nanoparticles are gaining importance on account of its antimicrobial properties and low toxicity to humans. The present study was conducted to synthesise silver nanoparticles (AgNPs) from aqueous extract of neem leaves. The phytochemical screening of the aqueous extract of neem leaves was also performed for determining its active principles. The qualitative phytochemical screening revealed that the aqueous extract of neem leaves contained phytochemicals like steroids, alkaloids, phenolic compounds, tannins, flavonoids, saponins and terpenoids. The AgNPs synthesised were characterised using X-ray diffraction analysis which revealed that synthesised AgNPs were face centred, cubic and crystalline in nature and the sample contained silver nanoparticles in a high concentration. The antibacterial activity of the green AgNPs against E. coli isolates including the reference strain was tested and observed that the AgNPs exhibited antibacterial activity though a significant zone of inhibition was not obtained. Based on the results obtained, it could be concluded that silver nanoparticles could be efficiently synthesised from neem leaves and could be utilised in various fields especially in nanotechnology.