期刊
FREE RADICAL BIOLOGY AND MEDICINE
卷 51, 期 10, 页码 1872-1881出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.freeradbiomed.2011.08.025
关键词
Bacteria; Nanoparticles; Oxidative stress; Genotoxicity; Ecotoxicity; Free radicals
资金
- CSIR, New Delhi [NWP34, NWP35, OLP009]
- Department of Science and Technology-UK India Education and Research Initiative [DST/INT/UKIERI/SA/P-10/2008]
- Department of Science and Technology, New Delhi, India [SR/S5/NM-01/2007]
- Department of Biotechnology, Government of India
- Indian Council of Medical Research, New Delhi
Extensive use of engineered nanoparticle (ENP)-based consumer products and their release into the environment have raised a global concern pertaining to their adverse effects on human and environmental health. The safe production and use of ENPs requires improvement in our understanding of environmental impact and possible ecotoxicity. This study explores the toxicity mechanism of ZnO and TiO2 ENPs in a gram-negative bacterium, Escherichia coli. Internalization and uniform distribution of characterized bare ENPs in the nano range without agglomeration was observed in E. coli by electron microscopy and flow cytometry. Our data showed a statistically significant concentration-dependent decrease in E. coli cell viability by both conventional plate count method and flow cytometric live-dead discrimination assay. Significant (p<0.05) DNA damage in E. coli cells was also observed after ENP treatment. Glutathione depletion with a concomitant increase in hydroperoxide ions, malondialdehyde levels, reactive oxygen species, and lactate dehydrogenase activity demonstrates that ZnO and TiO2-ENPs induce oxidative stress leading to genotoxicity and cytotoxicity in E. coli. Our study substantiates the need for reassessment of the safety/toxicity of metal oxide ENPs. (C) 2011 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据