Self-potent anti-microbial and anti-fouling action of silver nanoparticles derived from lichen-associated bacteria

Controlling and eradicating microbial existence require an interdisciplinary framework involving nanomaterials to develop innovative anti-bacterial agents. Especially, sustainable and eco-friendly synthesis of nanoparticles has been realized to be beneficial. Herein, the work focuses on a simple, low-cost, and environmentally benign microbial production of Ag nanoparticles for anti-fouling application. The synthesized Ag nanoparticles were analyzed using UV–visible spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray analysis (EDAX), and Fourier Transform Infrared Spectroscopy (FTIR). The XRD spectra of the synthesized Ag Nps exhibit the existence of crystalline Ag Nps with spherical shape prominence in size range of 40–50 nm. The FTIR spectrum shows the band at 2853 cm −1 corresponding to alkyne stretch and 1384 cm −1 to the proximity of the amide group (NH) in bending mode. The absorbance peak of produced Ag nanoparticles was ~ 450 nm, and the highest retention time was obtained for the compound Oxirane, 2-butyl-3-methyl-, cis- for the extract without AgNO 3 and (2s,3s)-(-)-3-propyloxiranemethanol along with the AgNO 3 , analyzed using GCMS. Furthermore, the anti-bacterial activity of Ag nanoparticles (5 mM AgNO 3 ) generated using the S-I bacterial strain was tested against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli, with a maximal zone of inhibition of 31 mm against E. coli . The anti-fouling coating of Ag nanoparticles prevented bacterial colonies from growing with a zone diameter of 26 mm. Surprisingly, the low-cost Ag nanoparticles generated have both anti-bacterial and anti-fouling properties, making them ideal for use as surface coating additives for submarines and other water transport vehicles.