Antimicrobial properties of green synthesized silver nanoparticles from Diplazium maximum (D. Don) C. Chr.

Abstract

Diplazium maximum is a wild edible fern species rich in different bioactive compounds (polypeptides, flavonoids, phenolics, alkaloids, saponins, steroids, tannins, and glycosides), and has been used by local healers for treating several ailments. For the first time, the antimicrobial activity of silver nanoparticles derived from this species was assessed scientifically in vitro, which were further characterized following UV-Visible Spectroscopy, X-Ray Diffraction, Atomic Force Microscopy, Fourier Transform Infrared Spectroscopy, Field Emission Scanning Electron Microscopy, and High-Resolution Transmission Electron Microscopy. These studies confirmed synthesis of quasi-spherical shaped nanoparticles with average size of 17.0 ± 7.85 nm which were most effective against Pseudomonas aeruginosa (13.83 ± 0.29 mm) followed by Bacillus cereus (12.25 ± 0.55 mm) at 180 µl (agar well diffusion assay). While they were most inhibitory against B. cereus and Aspergillus niger (Minimum Inhibitory Concentration: 0.0781 mg/100 µl) than crude extract. Hence, with nano-technological interventions, D. maximum antimicrobial efficacy can be enhanced, and also this species serves as a strong candidate for future herbal drug development, which are not only efficient but also eco-friendly.