Abstract
Language | English |
---|---|
Pages | 51-54 |
Number of pages | 3 |
Journal | Journal of Food Agriculture and Environment |
Volume | 7 |
Issue number | 3-4 |
Publication status | Published - Jul 2009 |
Fingerprint
Keywords
- heat-stressed escherichia coli
- salt concentration
- growth
Cite this
}
Effect of salt concentrations on the growth of heat-stressed and unstressed escherichia coli. / Abdulkarim, S.M.; Fatimah, A.B.; Anderson, J.G.
In: Journal of Food Agriculture and Environment , Vol. 7, No. 3-4, 07.2009, p. 51-54.Research output: Contribution to journal › Article
TY - JOUR
T1 - Effect of salt concentrations on the growth of heat-stressed and unstressed escherichia coli
AU - Abdulkarim, S.M.
AU - Fatimah, A.B.
AU - Anderson, J.G.
PY - 2009/7
Y1 - 2009/7
N2 - The effect sodium chloride (NaCl) and potassium chloride (KCl) concentration on the growth of Escherichia coli cells cultivated at 37 and 44°C was studied in an effort to understand the importance of the salts and glucose in medium to the growth of E. coli. A turbidimetric method was used to measure the growth of E. coli after a 24 hours incubation period. The turbidimetric method used gave a high correlation (R2 = 0.9606) with the traditional surface colony count method. Four sets of salt concentrations, 0, 0.5, 1.0 and 1.5% (w/v), were employed throughout this study. Absence of NaCl in the medium was found to slightly decrease the growth of E. coli at 37°C. E. coli grew optimally at 0.5% (w/v) NaCl concentration. Addition of 0.5% KCl was found to have less beneficial effect on the growth of E. coli at 37°C compared to cells grown in medium with 0.5% NaCl. Increase in the concentrations of both salts above 0.5% decreased growth at 37°C. The extent to which growth was suppressed was directly proportional to the concentration of salts. At zero concentration of both salts, growth of E. coli was very low at 44°C. Increase in the concentrations of both NaCl and KCl from 0.5% to 1.5% resulted in growth enhancement. Glucose affected significantly the growth of E. coli at 37°C. Addition of 140 mM (w/ v) of glucose to the medium increased the growth of E. coli at 37°C to a greater extent than was obtained by salt addition. However, the addition of the same concentration of glucose was found to have only a very slight effect on growth at 44°C.
AB - The effect sodium chloride (NaCl) and potassium chloride (KCl) concentration on the growth of Escherichia coli cells cultivated at 37 and 44°C was studied in an effort to understand the importance of the salts and glucose in medium to the growth of E. coli. A turbidimetric method was used to measure the growth of E. coli after a 24 hours incubation period. The turbidimetric method used gave a high correlation (R2 = 0.9606) with the traditional surface colony count method. Four sets of salt concentrations, 0, 0.5, 1.0 and 1.5% (w/v), were employed throughout this study. Absence of NaCl in the medium was found to slightly decrease the growth of E. coli at 37°C. E. coli grew optimally at 0.5% (w/v) NaCl concentration. Addition of 0.5% KCl was found to have less beneficial effect on the growth of E. coli at 37°C compared to cells grown in medium with 0.5% NaCl. Increase in the concentrations of both salts above 0.5% decreased growth at 37°C. The extent to which growth was suppressed was directly proportional to the concentration of salts. At zero concentration of both salts, growth of E. coli was very low at 44°C. Increase in the concentrations of both NaCl and KCl from 0.5% to 1.5% resulted in growth enhancement. Glucose affected significantly the growth of E. coli at 37°C. Addition of 140 mM (w/ v) of glucose to the medium increased the growth of E. coli at 37°C to a greater extent than was obtained by salt addition. However, the addition of the same concentration of glucose was found to have only a very slight effect on growth at 44°C.
KW - heat-stressed escherichia coli
KW - salt concentration
KW - growth
UR - http://www.world-food.net/scientficjournal/2009/issue3/pdf/food/9.pdf
M3 - Article
VL - 7
SP - 51
EP - 54
JO - Journal of Food Agriculture and Environment
T2 - Journal of Food Agriculture and Environment
JF - Journal of Food Agriculture and Environment
SN - 1459-0255
IS - 3-4
ER -