Nanosilver-Mediated Change in Human Intestinal MicrobiotaPranab Das1*, Julie AK McDonald2, Elaine O Petrof2, Emma Allen-Vercoe3and Virginia K Walker1,4
- *Corresponding Author:
- Pranab Das
Department of Biology, Queen’s University
Biosciences Complex, Room 2521, Kingston
ON, K7L 3N6, Canada
Tel: 1-613- 533-6000
E-mail: [email protected]
Received Date: September 17, 2014; Accepted Date: October 09, 2014; Published Date: October 18, 2014
Citation: Das P, McDonald JAK, Petrof EO, Allen-Vercoe E, Walker VK (2014) Nanosilver-Mediated Change in Human Intestinal Microbiota. J Nanomed Nanotechnol 5:235. doi:10.4172/2157-7439.1000235
Copyright: © 2014 Das P, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The widespread use of silver nanoparticles (AgNPs) has prompted studies on different species and at various trophic levels, however, little is known about possible toxicological impacts on their corresponding microbiota. Here the effects of AgNPs on a defined bacterial community established from the collected stool of a healthy donor have been investigated. The anaerobic consortium was exposed to several concentrations (0 – 200 mg/L) of AgNPs (capped; 10 nm) for 48 h. Nanosilver had a negative impact on the bacterial community as evidenced by a significant reduction (~22%) in culture-generated gas production at the two highest AgNP concentrations compared to controls, as well as significant (p<0.05) changes in fatty acid methyl ester profiles even at the lowest concentration. DNA analysis confirmed these observations showing a shift in the community structure as demonstrated by cluster analysis of PCR-denaturing gradient gel electrophoresis (DGGE) profiles, as well by phylogenetic distributions obtained from 454 pyrotag 16S rRNA gene sequencing. The bacterial assemblage was significantly (p<0.01) different in the AgNP- treatment groups compared to controls. As expected, ionic silver (AgCl; 25-200 mg/L) was also antibacterial, as shown by all four assessment methods, but its effects were distinct from the AgNP-mediated changes. Thus, nano size-dependent impacts were evident. Taken together, these experiments suggest that AgNP ingestion, either deliberate or inadvertent, could have negative consequences on our intestinal microbiota.