Assessment of antimicrobial activity of phytofabricated silver particles

Nanobiotechnology is emerging as a field of nanotechnology and applied biological science. Nanoparticles are produced by physical, chemical and biological methods; but biological methods are relatively cost effective, non-toxic, simple and eco-friendly. The present study was carried out focusing on the antimicrobial activities of phytofabricated silver nanoparticles of Curcuma longa, Eucalyptus camaldulensis, Syzygium cumini, Viola betonicifolia and Mangifera indica. The biogenic fabrications of silver nanoparticles were characterized by ultraviolet–visible (UV–Vis) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The UV–Vis spectra of the different plant extracts in aqueous medium containing silver nanoparticles showed peaks in the visible region. FT-IR spectroscopy showed that the nanoparticles are capped with the chemical constituents of plant extracts. SEM was used to estimate the morphology of the nanoparticles capped with plant extracts. The antimicrobial activities of the phytofabricated silver nanoparticles were studied against Escherichia coli and Bacillus subtilis. Maximum antibacterial activity was observed for phytofabricated silver nanoparticles of S. cumini against E. coli (32 ± 0·28 mm) and B. subtilis (26 ± 0·288 mm) and E. camaldulensis against E. coli (31·33 ± 0·011 mm) and B. subtilis (34 ± 0·064 mm) compared to simple plant extracts of S. cumini against E. coli (25 ± 0·5 mm) and B. subtilis (24·66 ± 0·01 mm) and E. camaldulensis against E. coli (36 ± 0·450 mm) and B. subtilis (32 ± 0·38 mm). The selected biomimetic silver nanoparticles and their fractions in different solvents show maximum antimicrobial potential compared with plain plant extracts and their fractions.