The effect of incubation temperature, initial pH, and sodium chloride on the growth kinetics of Escherichia coli O157:H7

摘要: The 6 effects of initial pH, sodium chloride content, and incubation temperature on the aerobic anaerobic growth kinetics a three strain mixture Escherichia coli O157:H7 were evaluated using brain heart infusion broth. variables interacted to affect growth, with primary being noted in relation generation times (GTs) lag phase durations (LPDs). maximum population densities (MPDs) achieved by cultures largely independent variables; however, there was general depression MPDs 0·5–1·0 log cycles when incubated anaerobically. Under otherwise optimal conditions, GTs LPDs unaffected pH at values ⩾ 5·5. Initial had greater effect NaCl content elevated. Increasing levels decreased rate organism, if other also non-optimal. In general, could be adequately described Ratkowsky square root function; temperatures an increase differential between Tmin actual that did not support as became Comparison current data previous reports suggest E. are similar those for non-pathogenic strains.