The effects of temperature, water activity and pH on the growth of Aeromonas hydrophila and on its subsequent survival in microcosm water

Abstract

Aims: The influence of temperature, water activity and pH on the growth of Aeromonas hydrophila, and on its survival after transfer in nutrient-poor water were assessed. Methods and Results: Experiments were carried out according to a Box-Behnken matrix at 10-30°C, 0AE95-0AE99 water activity (a w ) and pH 5-9. The effect of each factor on the kinetic parameters of growth (i.e. the maximal specific growth rate, l max , and the lag time, k) and on the decline of the bacteria in microcosm water (time to obtain a reduction of 5 log, T 5 log ) were studied by applying central composite design. Conclusions: The major effect of temperature and water activity on the growth of A. hydrophila was highlighted, whereas the effect of pH in these experimental conditions was not significant. Models describing the effect of environmental parameters on the growth of A. hydrophila were proposed. The effect of the growth environment, and particularly the incubation temperature, have an influence on the survival ability of the bacteria in nutrient-poor water. Significance and Impact of the Study: The Box-Behnken design was well suited to determine the influence of environmental factors on the growth of A. hydrophila and to investigate the effect of previous growth conditions on its survival in microcosm water.

Dynamics of Aeromonas species isolated from wastewater treatment system

“…The absence of correlation can be explained by differences in characteristics of each group of organisms, such as occurrence of enteric organisms, in the case of E. coli. On the other hand, the genus Aeromonas can get into the stabilization pond system through the faecal pathway, even though they are primarily ubiquitous in the aquatic environment, where they can multiply or tolerate changes in dynamics, association to and/or competition with bacterial flora, and other environmental variations (Hassani et al 1992;Benchokroun et al 2003;Maalej et al 2003;Sautour et al 2003;Blasco et al 2008). In the present study, most of the known species of…”

A Box-Behnken design for predicting the combined effects of relative humidity and temperature on antagonistic yeast population density at the surface of apples

“…The Box-Behnken design minimizes the number of factor combinations and maintains good precision of the predicted response. It has been widely used to predict the growth of food-borne pathogens in relation to at least three environment factors (Sautour et al, 2003).…”

The Study on Effect of Temperature Stress on Occurrence of Clinical Signs Caused by Aeromonas hydrophila in Capoeta damascina in In Vitro Condition

“…On the other hands, Ishiguro et al (1981) reported that A. salmonicida lost its virulence when cultured at high temperatures. Results of Sautour et al (2003) and showed among the three factors tested including temperature, water activity and pH, temperature has the main influence on growth and survival of A. hydrophila in microcosm water. These results confirmed current findings.…”

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