Back to Journals » International Journal of Nanomedicine » Volume 8 » Issue 1

Synthesis, optimization, and characterization of silver nanoparticles from Acinetobacter calcoaceticus and their enhanced antibacterial activity when combined with antibiotics

Authors Singh R, Wagh P, Wadhwani S, Gaidhani S, Kumbhar A, Bellare J, Chopade BA

Received 23 May 2013

Accepted for publication 30 June 2013

Published 6 November 2013 Volume 2013:8(1) Pages 4277—4290

DOI https://doi.org/10.2147/IJN.S48913

Checked for plagiarism Yes

Review by Single-blind

Peer reviewer comments 3

Richa Singh,1 Priyanka Wagh,1 Sweety Wadhwani,1 Sharvari Gaidhani,2 Avinash Kumbhar,3 Jayesh Bellare,4 Balu Ananda Chopade1

1Department of Microbiology, University of Pune, Pune, Maharashtra, India; 2Institute of Bioinformatics and Biotechnology, University of Pune, Pune, Maharashtra, India; 3Department of Chemistry, University of Pune, Pune, Maharashtra, India; 4Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India

Background: The development of nontoxic methods of synthesizing nanoparticles is a major step in nanotechnology to allow their application in nanomedicine. The present study aims to biosynthesize silver nanoparticles (AgNPs) using a cell-free extract of Acinetobacter spp. and evaluate their antibacterial activity.
Methods: Eighteen strains of Acinetobacter were screened for AgNP synthesis. AgNPs were characterized using various techniques. Reaction parameters were optimized, and their effect on the morphology of AgNPs was studied. The synergistic potential of AgNPs on 14 antibiotics against seven pathogens was determined by disc-diffusion, broth-microdilution, and minimum bactericidal concentration assays. The efficacy of AgNPs was evaluated as per the minimum inhibitory concentration (MIC) breakpoints of the Clinical and Laboratory Standards Institute (CLSI) guidelines.
Results: Only A. calcoaceticus LRVP54 produced AgNPs within 24 hours. Monodisperse spherical nanoparticles of 8–12 nm were obtained with 0.7 mM silver nitrate at 70°C. During optimization, a blue-shift in ultraviolet-visible spectra was seen. X-ray diffraction data and lattice fringes (d =0.23 nm) observed under high-resolution transmission electron microscope confirmed the crystallinity of AgNPs. These AgNPs were found to be more effective against Gram-negative compared with Gram-positive microorganisms. Overall, AgNPs showed the highest synergy with vancomycin in the disc-diffusion assay. For Enterobacter aerogenes, a 3.8-fold increase in inhibition zone area was observed after the addition of AgNPs with vancomycin. Reduction in MIC and minimum bactericidal concentration was observed on exposure of AgNPs with antibiotics. Interestingly, multidrug-resistant A. baumannii was highly sensitized in the presence of AgNPs and became susceptible to antibiotics except cephalosporins. Similarly, the vancomycin-resistant strain of Streptococcus mutans was also found to be susceptible to antibiotic treatment when AgNPs were added. These biogenic AgNPs showed significant synergistic activity on the β-lactam class of antibiotics.
Conclusion: This is the first report of synthesis of AgNPs using A. calcoaceticus LRVP54 and their significant synergistic activity with antibiotics resulting in increased susceptibility of multidrug-resistant bacteria evaluated as per MIC breakpoints of the CLSI standard.

Keywords: Ag nanoparticles, lattice fringes, disc-diffusion, minimum inhibitory concentration, synergistic activity

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]

 

Other articles by this author:

Green synthesis of selenium nanoparticles using Acinetobacter sp. SW30: optimization, characterization and its anticancer activity in breast cancer cells

Wadhwani SA, Gorain M, Banerjee P, Shedbalkar UU, Singh R, Kundu GC, Chopade BA

International Journal of Nanomedicine 2017, 12:6841-6855

Published Date: 13 September 2017

Phytogenic silver, gold, and bimetallic nanoparticles as novel antitubercular agents

Singh R, Nawale L, Arkile M, Wadhwani S, Shedbalkar U, Chopade S, Sarkar D, Chopade BA

International Journal of Nanomedicine 2016, 11:1889-1897

Published Date: 4 May 2016

Readers of this article also read:

Improved antibacterial activity and biocompatibility on vancomycin-loaded TiO2 nanotubes: in vivo and in vitro studies

Zhang HZ, Sun Y, Tian A, Xue XX, Wang L, Alquhali A, Bai XZ

International Journal of Nanomedicine 2013, 8:4379-4389

Published Date: 8 November 2013

Microwave-assisted synthesis of SnO2 nanorods for oxygen gas sensing at room temperature

Azam A, Habib SS, Salah NA, Ahmed F

International Journal of Nanomedicine 2013, 8:3875-3882

Published Date: 9 October 2013

Vitamin C-driven epirubicin loading into liposomes

Lipka D, Gubernator J, Filipczak N, Barnert S, Süss R, Legut M, Kozubek A

International Journal of Nanomedicine 2013, 8:3573-3585

Published Date: 23 September 2013

Preparation, characterization, and in vivo pharmacokinetics of nanostructured lipid carriers loaded with oleanolic acid and gentiopicrin

Zhang KC, Lv SW, Li XY, Feng YF, Li X, Liu L, Li S, Li YJ

International Journal of Nanomedicine 2013, 8:3227-3239

Published Date: 22 August 2013

Enhanced bactericidal potency of nanoliposomes by modification of the fusion activity between liposomes and bacterium

Ma YF, Wang Z, Zhao W, Lu TL, Wang RT, Mei QB, Chen T

International Journal of Nanomedicine 2013, 8:2351-2360

Published Date: 28 June 2013

Biocompatibility of magnetic Fe3O4 nanoparticles and their cytotoxic effect on MCF-7 cells

Chen DZ, Tang QS, Li XD, Zhou XJ, Zang J, Xue WQ, Xiang JY, Guo CQ

International Journal of Nanomedicine 2012, 7:4973-4982

Published Date: 14 September 2012

Corrigendum

Wu Q, Chu M

International Journal of Nanomedicine 2012, 7:4531-4532

Published Date: 15 August 2012

Development of a reduction-sensitive diselenide-conjugated oligoethylenimine nanoparticulate system as a gene carrier

Cheng G, He Y, Xie L, Nie Y, He B, Zhang Z, Gu Z

International Journal of Nanomedicine 2012, 7:3991-4006

Published Date: 31 July 2012

Functionalization of single-walled carbon nanotubes and their binding to cancer cells

Madani SY, Tan A, Dwek M, Seifalian AM

International Journal of Nanomedicine 2012, 7:905-914

Published Date: 22 February 2012