Laser-Induced Breakdown Spectroscopy Based Study of Antimicrobial Attribute of Nano-Based Phytomaterial

摘要

Metal nanoparticles have enormous applications because of their distinct physicochemical attributes. The study deals with the laser induced breakdown spectroscopy (LIBS) studies and antimicrobial studies of Moringa oleifera leaf extract with silver nanoparticles and without silver nanoparticles on five different bacterial strains viz. Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis. Extent of inhibitory effect of both the extracts, with and without silver nanoparticles were assessed at a concentration range of 0.075-2.4 mg/ml. The results were compared with the standard antibiotic, Ciprofloxacin at the same concentration range. The phytofabricated silver nanoparticles in the extract of M. oleifera were found to enhance the antimicrobial efficacy of the extract against all the five tested microorganisms based on Minimum Inhibitory Concentration method. This enhancement is supposed to be due to the presence of silver nanoparticles in the extract as it is well known that silver oxidizes to ions which are fatal to bacteria and specifically in its nanosize which increases the number of ions. In addition to it, phytoconstituents also helps in stabilizing the AgNP so that they can get oxidized for a longer period. Moreover, LIBS data also reveals the presence of a set of elements well known for their antibacterial activity viz. Ca, Mg, Fe in addition to Ag.