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Journal of Biological Sciences

Year: 2002 | Volume: 2 | Issue: 7 | Page No.: 483-484
DOI: 10.3923/jbs.2002.483.484
Effect of NaCl on Heat Tolerance of Enterococcus faecium and Enterococcus faecalis
Mushtaq Ahmad, David G. Smith and Shahid Mahboob

Abstract: The effect of NaCl on heat tolerance of Enterococcus faecium BAR1 and Enterococcus faecalis MI2 was determined at 55, 60 and 62.5oC for half an hour. Cells of both isolates were grown in Brain Heart Infusion broth containing 6.5% NaCl. Exponential phase cells were used as inoculants. Cells of both isolates were found resistant to heat treatment as compared with cells grown in BHI broth without presence of salt. The decimal reduction times (D-values) were determined by 1 log fall in viable count. Both isolates showed similar results at 55oC but at 60oC E. faecalis MI2 showed higher D-value than E. faecium BAR1. At 62.5oC E. Faecium BAR1 was found more tolerant to heat treatment than E. faecalis MI2. Experiments showed that the presence of salt in the growth medium induces more heat tolerance in enterococci than the cells grown in normal medium.

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How to cite this article
Mushtaq Ahmad, David G. Smith and Shahid Mahboob, 2002. Effect of NaCl on Heat Tolerance of Enterococcus faecium and Enterococcus faecalis. Journal of Biological Sciences, 2: 483-484.

Keywords: Enterococci, NaCl, D-value and heat tolerance

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