An insight study on HPTLC fingerprinting of Mukia maderaspatna : Mechanism of bioactive constituents in metal nanoparticle synthesis and its activity against human pathogens

Minimum bactericidal concentration of chemically synthesized silver nanoparticles against pathogenic Salmonella and Shigella strains isolated from layer poultry farms

“…In previous studies, the MIC of a chemically synthesized nanoparticles (30-40 nm) against Salmonella were reported at 2.81 μgml -1 . Moreover, the efficient bactericidal activity of AgNPs was obtained at its lowest concentration of 0.35 μgml -1 (Devi et al, 2017). Furthermore, the MBC value of 100 nm sized AgNPs was ≈1 × 104 μgml -1 , while that for 5-10 nm sized AgNPs was 12-25 μgml -1 (Flores et al, 2013).…”

“…The AgNPs bactericidal properties are attributed mainly to their following abilities: bacterial cell walls and membrane destruction, reactive oxygen species (ROS) generation, vital metabolic enzyme inhibition, and obstruction of DNA replication (Feng et al, 2000;Sondi and Salopek-Sondi, 2004;Kim et al, 2007;Rai et al, 2009;Ahmad et al, 2017). AgNPs have the ability to attach and destruct bacterial cell walls in a dosedependent manner (Cerny and Teuber, 1971;Rhayour et al, 2003;Ahmad et al, 2017) this is confirmed by Electron spin resonance spectroscopy studies which demonstrated that when AgNPs attached to the bacterial cell walls, the free radicals of the AgNPs were then released (Danilcauk et al, 2006;Kim et al, 2007;Swarnavalli et al, 2017).…”

“…These released free radical seems to be the main causative agent responsible for final bacterial destruction and death (Devi et al, 2017); as these free radicals begin to make pores in the bacterial cell walls and membranes causing severe permeability of the bacterial cell membrane (Danilcauk et al, 2006;Kim et al, 2007;Swarnavalli et al, 2017), this is followed by releasing of periplasmic proteins and nucleic acids via cytoplasmic membrane, and so the bacterial cell death will be the final result (Cerny and Teuber, 1971;Rhayour et al, 2003;Ahmad et al, 2017;Swarnavalli et al, 2017). On the other hand, when AgNPs enter the bacterial cell, they form a low molecular weight region which begin to attack the respiratory chain, so consequently, the cellular signaling pathways will be changed by dephosphorylating assumed key peptide substrates on tyrosine residues (Sondi and Salopek-Sondi, 2004;Mulley et al, 2014;Su et al, 2017b).…”

“…Indeed, nanoparticles have been gaining importance in recent years and became an effective revolution therapy against pathogenic bacteria due to their bactericidal properties. The nanoparticles size and surface area are significant agents to which their bactericidal mechanism of action attributed to (Devi et al, 2017). Silver nanoparticles (AgNPs) has been gaining importance in recent years due to their broad spectrum bactericidal toxic effects against broad spectrum pathogenic bacteria (Ahmad et al, 2017) even at their minimum concentrations (Devi et al, 2017).…”

“…The nanoparticles size and surface area are significant agents to which their bactericidal mechanism of action attributed to (Devi et al, 2017). Silver nanoparticles (AgNPs) has been gaining importance in recent years due to their broad spectrum bactericidal toxic effects against broad spectrum pathogenic bacteria (Ahmad et al, 2017) even at their minimum concentrations (Devi et al, 2017). Furthermore, the results offered by suggest that AgNPs can be used as potent bactericidal agents against antibiotic-resistant bacteria.…”