Abstract
The interaction of temperature (10, 14, 25, 31, and 37 degrees C), pH (pH 5, 5.6, 6.5, 7.4, and 8), and NaCl (0, 2, 5, 8, and 10%) in a laboratory medium affects the specific growth of Staphylococcus aureus. From growth curves obtained by the turbidimetric technique, a nonlinear model in which the specific growth rate (mu) is fitted directly, without data transformation and with the residual error variations taken into account, is proposed. This model correctly fits experimental data and gives more biological information than the quadratic polynomial model. Moreover, the comparison of five strains of S. aureus was performed by a principal-component analysis in which the specific growth rate was the identifying characteristic for S. aureus strains. The results obtained from model coefficient comparison among the five strains and from multivariate data analysis allow the same classification of strains to be performed. Two of them have similar behaviors during food spoilage, two others could be distinguished by their capacity to grow at a low temperature, whereas the last one was markedly different from the others.
Full Text
The Full Text of this article is available as a PDF (250.6 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Adams M. R., Little C. L., Easter M. C. Modelling the effect of pH, acidulant and temperature on the growth rate of Yersinia enterocolitica. J Appl Bacteriol. 1991 Jul;71(1):65–71. [PubMed] [Google Scholar]
- Davey K. R. A predictive model for combined temperature and water activity on microbial growth during the growth phase. J Appl Bacteriol. 1989 Nov;67(5):483–488. doi: 10.1111/j.1365-2672.1989.tb02519.x. [DOI] [PubMed] [Google Scholar]
- Gibson A. M., Bratchell N., Roberts T. A. Predicting microbial growth: growth responses of salmonellae in a laboratory medium as affected by pH, sodium chloride and storage temperature. Int J Food Microbiol. 1988 Mar;6(2):155–178. doi: 10.1016/0168-1605(88)90051-7. [DOI] [PubMed] [Google Scholar]
- Membré J. M., Burlot P. M. Effects of Temperature, pH, and NaCl on Growth and Pectinolytic Activity of Pseudomonas marginalis. Appl Environ Microbiol. 1994 Jun;60(6):2017–2022. doi: 10.1128/aem.60.6.2017-2022.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schoolfield R. M., Sharpe P. J., Magnuson C. E. Non-linear regression of biological temperature-dependent rate models based on absolute reaction-rate theory. J Theor Biol. 1981 Feb 21;88(4):719–731. doi: 10.1016/0022-5193(81)90246-0. [DOI] [PubMed] [Google Scholar]
- Sutherland J. P., Bayliss A. J., Roberts T. A. Predictive modelling of growth of Staphylococcus aureus: the effects of temperature, pH and sodium chloride. Int J Food Microbiol. 1994 Feb;21(3):217–236. doi: 10.1016/0168-1605(94)90029-9. [DOI] [PubMed] [Google Scholar]
- Zwietering M. H., Jongenburger I., Rombouts F. M., van 't Riet K. Modeling of the bacterial growth curve. Appl Environ Microbiol. 1990 Jun;56(6):1875–1881. doi: 10.1128/aem.56.6.1875-1881.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]