Priyanka Singh1, Santosh Pandit2, Carsten Jers1, Abhayraj S Joshi1, Jørgen Garnæs3, Ivan Mijakovic4,5. 1. The Novo Nordisk Foundation, Center for Biosustainability, Technical University of Denmark, 2800, Lyngby, Denmark. 2. Systems and Synthetic Biology Division, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden. 3. Danish Fundamental Metrology, Kogle Allé 5, 2970, Hørsholm, Denmark. 4. The Novo Nordisk Foundation, Center for Biosustainability, Technical University of Denmark, 2800, Lyngby, Denmark. ivan.mijakovic@chalmers.se. 5. Systems and Synthetic Biology Division, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden. ivan.mijakovic@chalmers.se.
Abstract
With multidrug-resistant bacterial pathogens on the rise, there is a strong research focus on alternative antibacterial treatments that could replace or complement classical antibiotics. Metallic nanoparticles, and in particular silver nanoparticles (AgNPs), have been shown to kill bacterial biofilms effectively, but their chemical synthesis often involves environmentally unfriendly by-products. Recent studies have shown that microbial and plant extracts can be used for the environmentally friendly synthesis of AgNPs. Herein we report a procedure for producing AgNPs using a putative Cedecea sp. strain isolated from soil. The isolated bacterial strain showed a remarkable potential for producing spherical, crystalline and stable AgNPs characterized by UV-visible spectroscopy, transmission electron microscopy, dynamic light scattering, and Fourier transform infrared spectroscopy. The concentration of produced nanoparticles was 1.31 µg/µl with a negative surface charge of - 15.3 mV and nanoparticles size ranging from 10-40 nm. The AgNPs was tested against four pathogenic microorganisms S. epidermidis, S. aureus, E. coli and P. aeruginosa. The nanoparticles exhibited strong minimum inhibitory concentration (MIC) values of 12.5 and 6.25 µg/µl and minimum bactericidal concentration (MBC) values of 12.5 and 12.5 µg/mL against E. coli and P. aeruginosa, respectively. One distinguishing feature of AgNPs produced by Cedecea sp. extracts is their extreme stability. Inductively coupled plasma mass spectrometry and thermogravimetric analysis demonstrated that the produced AgNPs are stable for periods exceeding one year. This means that their strong antibacterial effects, demonstrated against E. coli and P. aeruginosa biofilms, can be expected to persist during extended periods.
With multidrug-resistant bacterial pathogens on the rise, there is a strong research focus on alternative antibacterial treatments that could replace or complement classical antibiotics. Metallic nanoparticles, and in particular n class="Chemical">silver nanoparticles (AgNPs), have been shown to kill bacterial biofilms effectively, but their chemical synthesis often involves environmentally unfriendly by-products. Recent studies have shown that microbial and plant extracts can be used for the environmentally friendly synthesis of AgNPs. Herein we report a procedure for producing AgNPs using a putative Cedecea sp. strain isolated from soil. The isolated bacterial strain showed a remarkable potential for producing spherical, crystalline and stable AgNPs characterized by UV-visible spectroscopy, transmission electron microscopy, dynamic light scattering, and Fourier transform infrared spectroscopy. The concentration of produced nanoparticles was 1.31 µg/µl with a negative surface charge of - 15.3 mV and nanoparticles size ranging from 10-40 nm. The AgNPs was tested against four pathogenic microorganisms S. epidermidis, S. aureus, E. coli and P. aeruginosa. The nanoparticles exhibited strong minimum inhibitory concentration (MIC) values of 12.5 and 6.25 µg/µl and minimum bactericidal concentration (MBC) values of 12.5 and 12.5 µg/mL against E. coli and P. aeruginosa, respectively. One distinguishing feature of AgNPs produced by Cedecea sp. extracts is their extreme stability. Inductively coupled plasma mass spectrometry and thermogravimetric analysis demonstrated that the produced AgNPs are stable for periods exceeding one year. This means that their strong antibacterial effects, demonstrated against E. coli and P. aeruginosa biofilms, can be expected to persist during extended periods.
Authors: Hyun Koo; Raymond N Allan; Robert P Howlin; Paul Stoodley; Luanne Hall-Stoodley Journal: Nat Rev Microbiol Date: 2017-09-25 Impact factor: 60.633
Authors: Alexandra Y Grün; Constantin B App; Andreas Breidenbach; Jutta Meier; George Metreveli; Gabriele E Schaumann; Werner Manz Journal: PLoS One Date: 2018-06-14 Impact factor: 3.240