| Autor: |
Rangel K; FIOCRUZ, Center for Technological Development in Health (C.D.T.S.), National Institute of Science and Technology for Innovation in Neglected Population Diseases (INCT-IDPN), Rio de Janeiro 21040-900, RJ, Brazil., Cabral FO; Microbiology Department, National Institute for Quality Control in Health (I.N.C.Q.S.), FIOCRUZ, Rio de Janeiro 21040-900, RJ, Brazil., Lechuga GC; FIOCRUZ, Center for Technological Development in Health (C.D.T.S.), National Institute of Science and Technology for Innovation in Neglected Population Diseases (INCT-IDPN), Rio de Janeiro 21040-900, RJ, Brazil., Carvalho JPRS; FIOCRUZ, Center for Technological Development in Health (C.D.T.S.), National Institute of Science and Technology for Innovation in Neglected Population Diseases (INCT-IDPN), Rio de Janeiro 21040-900, RJ, Brazil.; Department of Molecular and Cellular Biology, Biology Institute, Federal Fluminense University, Niteroi 22040-036, RJ, Brazil., Villas-Bôas MHS; Microbiology Department, National Institute for Quality Control in Health (I.N.C.Q.S.), FIOCRUZ, Rio de Janeiro 21040-900, RJ, Brazil., Midlej V; Laboratory of Cellular and Ultrastructure, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040-900, RJ, Brazil., De-Simone SG; FIOCRUZ, Center for Technological Development in Health (C.D.T.S.), National Institute of Science and Technology for Innovation in Neglected Population Diseases (INCT-IDPN), Rio de Janeiro 21040-900, RJ, Brazil.; Department of Molecular and Cellular Biology, Biology Institute, Federal Fluminense University, Niteroi 22040-036, RJ, Brazil.; Epidemiology and Molecular Systematic Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040-900, RJ, Brazil. |
| Abstrakt: |
(1) Background: Disinfection of medical devices designed for clinical use associated or not with the growing area of tissue engineering is an urgent need. However, traditional disinfection methods are not always suitable for some biomaterials, especially those sensitive to chemical, thermal, or radiation. Therefore, the objective of this study was to evaluate the minimal concentration of ozone gas (O 3 ) necessary to control and kill a set of sensitive or multi-resistant Gram-positive and Gram-negative bacteria. The cell viability, membrane permeability, and the levels of reactive intracellular oxygen (ROS) species were also investigated; (2) Material and Methods: Four standard strains and a clinical MDR strain were exposed to low doses of ozone at different concentrations and times. Bacterial inactivation (cultivability, membrane damage) was investigated using colony counts, resazurin as a metabolic indicator, and propidium iodide (PI). A fluorescent probe (H 2 DCFDA) was used for the ROS analyses; (3) Results: No reduction in the count colony was detected after O 3 exposure compared to the control group. However, the cell viability of E. coli (30%), P. aeruginosa (25%), and A. baumannii (15%) was reduced considerably. The bacterial membrane of all strains was not affected by O 3 but presented a significant increase of ROS in E. coli (90 ± 14%), P. aeruginosa (62.5 ± 19%), and A. baumanni (52.6 ± 5%); (4) Conclusion: Low doses of ozone were able to interfere in the cell viability of most strains studied, and although it does not cause damage to the bacterial membrane, increased levels of reactive ROS are responsible for causing a detrimental effect in the lipids, proteins, and DNA metabolism. |
