A RAPID METHOD FOR THE DETERMINATION OF BACTERIAL GROWTH KINETICS 1

Abstract
We have developed a rapid method for the determination of lag times and specific growth rates for bacteria. This method involves the use of a Bio‐Tek model EL312 microtiter plate (MP) reader, controlled by KinetiCalc software, and uses a computer program that processes absorbance data from a 96‐well MP. The program reads an ASCII file consisting of optical density readings generated by the MP reader, sorts the data into individual growth curves, and determines growth kinetics. No statistically significant difference (P > 0.88) was found between the MP method and standard batch methods. This method allows up to 95 growth curves to be carried out simultaneously. The MP method automates the difficult task of determining growth kinetics for bacterial strains under conditions that result in slow growth rates or long lag times. Using this method we determined the effect of NaCl on the growth kinetics of Listeria monocytogenes and the effects of NaCl and temperature on the growth kinetics of Leuconostoc mesenteroides.