DESIGN AND TESTING OF A CALORIMETER FOR MICROBIOLOGICAL USES

Abstract

A rotatory calorimeter of the conduction type was remodeled to fit the continuous study of microbiological processes. Provisions for aeration and agitation made it possible to do calorimetric studies of microorganisms aerobically growing in a 5-ml culture. The time constant of the calorimeter response was 8 min and the calorimeter could be used for most kinetic studies on microbial cultures. Using a separate culture apparatus, quantitative analyses can be made on samples taken from parallel culture and the results can be correlated with the thermogram obtained with the calorimeter. The performance of the instrument was demonstrated with the aerobic growth of Saccharomyces cerevisiae. Calorimetric study by the presented model may give detailed information at the cellular level about microbial growth processes when combined with turbidity measurements.