Efficiency of Biosynthesized Silver and Zinc Nanoparticles Against Multi-Drug Resistant Pathogens

Abstract

Biosynthesis of metallic nanoparticles has acquired particular attention due to its economic feasibility, low toxicity, and simplicity of the process. In this study, extracellular synthesis of silver and zinc nanoparticle was carried out by Pseudomonas hibiscicola isolated from the effluent of an electroplating industry in Mumbai. Characterization studies revealed synthesis of 40 and 60 nm nanoparticles of silver (AgNP) and zinc (ZnNP), respectively, with distinct morphology as observed in TEM and its crystalline nature confirmed by XRD. DLS, zeta potential, NTA, and FTIR studies further characterized nanoparticles giving data about its size, stability, and functional groups. Considering the toxicity of nanoparticles the evaluation of antimicrobial activity was studied in the range of non-toxic concentration for normal cell lines. Silver nanoparticles were found to be the most effective antimicrobial against all tested strains and drug-resistant clinical isolates of MRSA, VRE, ESBL, MDR, Pseudomonas aeruginosa with MIC in the range of 1.25–5 mg/ml. Zinc nanoparticles were found to be specifically active against Gram-positive bacteria like Staphylococcus aureus including its drug-resistant variant MRSA. Both AgNP and ZnNP were found to be effective against Mycobacterium tuberculosis and its MDR strain with MIC of 1.25 mg/ml. The synergistic action of nanoparticles assessed in combination with a common antibiotic gentamicin (590 μg/mg) used for the treatment of various bacterial infections by Checker board assay. Silver nanoparticles profoundly exhibited synergistic antimicrobial activity against drug-resistant strains of MRSA, ESBL, VRE, and MDR P. aeruginosa while ZnNP were found to give synergism with gentamicin only against MRSA. The MRSA, ESBL, and P. aeruginosa strains exhibited MIC of 2.5 mg/ml except VRE which was 10 mg/ml for both AgNPs and ZnNPs. These results prove the great antimicrobial potential of AgNP and ZnNP against drug-resistant strains of community and hospital-acquired infections and opens a new arena of antimicrobials for treatment, supplementary prophylaxis, and prevention therapy.

Effect of antimicrobial nanocomposites on Vibrio cholerae lifestyles: Pellicle biofilm, planktonic and surface-attached biofilm

“…Although there is a lower bacterial population, SEM images from PB and SB revealed no changes in bacteria morphology in the three treatments analyzed (Figs 2 and 4). It is important to mention the low toxicity found for ZEO-CuNPs and ZEO-ZnNPs, whose antimicrobial effects as zero-dimensional metallic nanoparticles are well documented [34,35]. The oxidation state of the CuNPs and ZnNPs within the zeolite matrix seems to be fundamental for its antimicrobial activity.…”

Silver Nanoparticles Derived from Albizia lebbeck Bark Extract Demonstrate Killing of Multidrug‐Resistant Bacteria by Damaging Cellular Architecture with Antioxidant Activity

“…Several studies reported the broad‐spectrum antimicrobial activity of silver nanoparticles, including the drug‐resistant S. aureus , K. pneumonia , E. coli , E. faecalis , P. aeruginosa , A. baumannii , and M. tuberculosis . The silver nanoparticles synthesized with AgNO 3 and leaf extract of Annona reticulata showed potent activity against Bacillus cereus and Staphylococcus aureus at 125 and 31.25 μg/mL; while it inhibits Escherichia coli , Pseudomonas aeruginosa and Candida albicans at 62.5 μg/mL .…”

“…The image also showed the damaged cell wall (pores) and cell membrane leading to the leakage of cytosolic content to lysis, compared to the untreated bacteria with normal rod‐shaped morphology, due to the differences in their sensitivity pattern (MIC 0.50 and 0.60 μM), along with variations in inoculum size, resistance level, peptidoglycan, biochemical and molecular structure as well as other components. Further, nanoparticles not only act on bacteria by direct contact, but also penetrate rapidly to interact with microbial DNA, that prevents the bacterial to develop resistance, and thus nanoparticles are less disposed to bacterial resistance . This suggests that Ag‐NP‐AE can be helpful in the management of those MDR‐bacterial infections.…”

Toxicity and application of nano-silver in multi-drug resistant therapy

“…Silver nanoparticles seem to be effective against drug-resistant strains of Methicillin-resistant staphylococcus aureus, extended-spectrum beta-lactamases, vancomycin-resistant enterococcus, and multi-drug resistant Pseudomonas aeruginosa. Therefore, it provides a potential antimicrobial effect against all drug-resistant strains and has a viable therapeutics candidate [23].…”