Evaluation of ultraviolet radiation to control microorganisms adhering to low-density polyethylene films
Braz. j. microbiol
; 34(2): 175-178, Apr.-Jun. 2003. ilus, tab, graf
Artigo
em Inglês
| LILACS
| ID: lil-355169
Biblioteca responsável:
BR32.1
ABSTRACT
Efficiency of ultraviolet (UV) radiation in reducing the cell number of Staphylococcus aureus ATCC 25923 and Escherichia coli K-12 adhered to low-density polyethylene (LDPE) films was evaluated. The microorganisms were let to adhere to the surface of LPDE bags for 12h at 18liC, and then submitted to UV radiation at an intensity 196 icW.cm-2, 254nm, for 2 seconds. Staphylococcus aureus was less resistant to UV radiation than E. coli, and the efficiency increased with the increase of the concentration of microbial suspension. After 1500 hours of use the UV radiation intensity of the lamp was reduced from 288 to 78 icW.cm-2, and the higher decrease occurred in the first 100 hours of use. Also, the efficiency of the UV radiation decreased after 1500 hours of use. The number of mesophilic aerobes on the surface of LDPE films was reduced by 90 percent after irradiation with 137 icW.cm-2 for 2 seconds. Atomic force microscopy revealed cracks and crevices and protuberances on the LDPE surface, a topography that can protect the cells from UV radiation, reducing the efficiency of the process. The results showed that UV radiation can be a useful technique for reducing the microbiota adhered to LDPE films.
Texto completo:
Disponível
Coleções:
Bases de dados internacionais
Contexto em Saúde:
ODS3 - Saúde e Bem-Estar
/
Doenças Negligenciadas
Problema de saúde:
Meta 3.3: Acabar com as doenças tropicais negligenciadas e combater as doenças transmissíveis
/
Doenças Negligenciadas
/
Zoonoses
Base de dados:
LILACS
Assunto principal:
Staphylococcus aureus
/
Raios Ultravioleta
/
Aderência Bacteriana
/
Esterilização
/
Escherichia coli
Idioma:
Inglês
Revista:
Braz. j. microbiol
Assunto da revista:
Microbiologia
Ano de publicação:
2003
Tipo de documento:
Artigo
País de afiliação:
Brasil
Instituição/País de afiliação:
Universidade Federal de Viçosa/BR