High throughput and rapid determination of the maximum specific growth rate of pathogenic and non-pathogenic Vibrio parahaemolyticus

Abstract:

[Objective] Comparing the variability of the maximum specific growth rate, μmax, of 9 different pathogenic and non-pathogenic V. parahaemolyticus strains in TSB (3% NaCl, pH 8.0) at 15 °C, 20 °C and 25 °C. [Methods] An automated turbidimetric system, Bioscreen C, was used to determine the μmax of strains of V. parahaemolyticus. [Results] The coefficient of variation of μmax among 9 V. parahaemolyticus strains was 20.72%, 17.5% and 15.98% at 15 °C, 20 °C and 25 °C, respectively. The variability of μmax among different V. parahaemolyticus strains increased as temperature was decreased. [Conclusion] A quantitative microbial risk assessment of V. parahaemolyticus infection and illness based on the growth characteristics of a single strain of V. parahaemolyticus, introduces a bias in the assessment. It’s necessary to develop stochastic models as the more precise and effective predictive model to be utilized in quantitative microbial risk assessment.

Key words:Vibrio parahaemolyticus, Maximum specific growth rate, Variability, Microbial risk assessment