Antiplanktonic, antibiofilm, antiswarming motility and antiquorum sensing activities of green synthesized Ag–TiO₂, TiO₂–Ag, Ag–Cu and Cu–Ag nanocomposites against multi-drug-resistant bacteria

Abstract

Fighting of current antibiotics against multidrug-resistant (MDR) bacteria has not been completely successful. In this study, the bio-synthesized Ag-TiO, TiO-Ag, Ag-Cu and Cu-Ag nanocomposites (NCs) were used against MDR bacteria including Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 (gram negative) and Staphylococcus aureus ATCC 43300 (gram positive). Antiplanktonic, antibiofilm, antiswarming motility and antiquorum sensing activities of these four NCs were measured by assays of agar well diffusion, minimum inhibition/minimum bactericidal concentrations (MIC/MBC), biofilm formation, biofilm morphology and pyocyanin amounts. Agar well diffusion method illustrated higher inhibition zone diameter (IZD) of Ag-TiO NCs with 13 ± 1, 16 ± 1.73 and 21.66 ± 1.52 mm against E. coli ATCC 25922, S. aureus ATCC 43300 and P. aeruginosa ATCC 27853 respectively. Swarming motility of P. aeruginosa at presence of NCs demonstrated lower density than control samples. Ordering of antibiofilm strength for these NCs was Ag-TiO > TiO-Ag > Cu-Ag > Ag-Cu. In addition, biofilm roughness and also pyocyanin synthesis as virulence factor related to quorum sensing mechanisms of P. aeruginosa ATCC 27853 was decreased under Ag-TiO NCs. In total, the present investigation illustrated eco-friendly and one-pot way to synthesize metal NCs with having significant antibacterial, antibiofilm and antiquorum sensing abilities.

Green synthesis of zinc oxide nanoparticles using different plant extracts and their antibacterial activity against Xanthomonas oryzae pv. oryzae

“…All the biologically synthesized ZnONPs were not significantly different from each other in the reduction of the halo diameter ( Figure 11). The ability of the nanoparticles to reduce biofilm formation and swimming motility of the bacterial is consistent with the studies of [54].…”

<p>Synergistic Nanocomposites of Different Antibiotics Coupled with Green Synthesized Chitosan-Based Silver Nanoparticles: Characterization, Antibacterial, in vivo Toxicological and Biodistribution Studies</p>

“…55 Nanocomposites of silver with other metals observed the disruption of biofilm structure and penetration of metal ions into under layers of bacterial colony. 56 Chitosan conjugated nanocomposites have profound antibacterial activity, due to the presence of an ammonia group in chitosan. Ammonia adsorbs on to the cell wall electrostatically and potentiates the destruction of cell wall by causing leaking of macromolecules from the bacterial cell.…”

Ultrasound assisted-phytofabricated Fe 3 O 4 NPs with antioxidant properties and antibacterial effects on growth, biofilm formation, and spreading ability of multidrug resistant bacteria

“…About 1% tannic acid (C 76 H 52 O 46 ) was used for 5 min following dehydration by increasing concentration of ethanol (20,40,60,80, and 100%). These samples were coated with gold or platinum for FE-SEM scanning analysis [42].…”