In-vitro Antimicrobial Activity of Green Synthesised Silver Nanoparticles of Leaf Extract of Rhinacanthus nasutus against Bacterial Food Borne Pathogens

Abstract

Introduction: Green synthesis of nanoparticles plays a major role in the control of virulent pathogens due to their ecofriendly, depreciated cost and naive nature. This peculiarity of plant based nanoparticle synthesis accomplishes them as fleeting development in nanobiotechnology. Rhinacanthus nasutus is one such plant, which is generally known as snake jasmine has prodigious medicinal properties to explore. Aim: The intent of this study was to harmonise silver nanoparticles (AgNPs) from leaves extract of Rhinacanthus nasutus (Snake jasmine) and interrogate its vitality against virulent bacteria secluded from food. Materials and Methods: The in-vitro study was conducted in Department of Microbiology at Muthayammal College of Arts and Science, Namakkal, Tamil Nadu, India, during November 2018 to November 2020. Nanoparticles were harmonised using 2 mM silver nitrate with leaves extract of Rhinacanthus nasutus which was then characterised by Ultraviolet-visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray (EDX) analysis and Transmission Electron Microscopy (TEM) imaging and Energy Dispersive X-Ray (EDX) analysis. Followed with this the antibacterial activity of silver nanoparticles was evaluated by agar well diffusion method against virulent bacteria isolated from food samples. Furthermore AgNPs was subjected to antibiofilm activity. Origin tool and Microsoft word 2010 were used for statistical analysis. Results: The green synthesis of silver nanoparticles possessed antibacterial activity against antibiotic resistant, biofilm and beta-lactamase producing Escherichia coli, Enterococcus spp, Klebsiella spp, Pseudomonas spp, Proteus spp, Staphylococcus spp, Salmonella spp and Shigella spp. Together with this the amalgamated AgNPs also exhibited antibiofilm activity in all the isolates. The better results of antibiofilm activity was observed against Salmonella species (74.1%). Conclusion: This study divulges the presence of substantial antibacterial activity of green synthesis of silver nanoparticles of Rhinacanthus nasutus leaves extract against virulent bacterial species. Hence, it can be explored and exploited for the formulation of new antimicrobial against biofilm and betalactamase producing bacterial isolates due to its modest and ecofriendly nature.