Evaluation of the antioxidant, antibacterial and anticancer (lung cancer cell line A549) activity of Punica granatum mediated silver nanoparticles

This work aimed to synthesize silver nanoparticles via an environmentally benign route, using the aqueous extract of Punica granatum as a precursor as well as a stabilizing and reducing agent. The as-synthesized silver nanoparticles were confirmed using UV-visible spectroscopy with an absorbance peak at 450 nm and were thereafter further confirmed using dynamic light scattering (DLS), High Resolution Transmission Electron Microscopy (HR-TEM) and X-Ray Diffraction (XRD). TEM analysis revealed 6-45 nm and spherically dispersed nanoparticles and XRD showed the crystalline nature of the nanoparticles. The free radical scavenging activity of the nanoparticles for DPPH and intracellular reactive oxidative species (ROS) production were observed using dihydroethidium (DHE) non-fluorescent stain and a CellROX (R) Deep Red fluorescent probe. Antibacterial assays against the most common Gram negative (Escherichia coli) and Gram positive (Staphylococcus aureus) bacteria showed a higher zone of inhibition against S. aureus. Furthermore, the anti-cancerous activity of the biologically synthesized silver nanoparticles was revealed by the inhibited cell growth of lung cancer A549 cells and no cytotoxicity was observed. This may be due to their ability to arrest the cell cycle at G1 phase. Thus, this work provides a gateway to explore more about the anticancer properties of biogenically synthesized silver nanoparticles and these biologically prepared silver nanoparticles have the potential to be utilized in biomedical science.