A Study of the Correlation of Acid Production and Population Growth in Escherichia Coli, Proteus Morgani and Shigella Sonnei

During the course of growth in a bacterial culture, cellular development and reproduction take place in a regular and orderly manner. It is possible to observe definite phases in the normal growth of a culture. Some method of evaluation of the growth must be used in order to determine the population change or the effect of chemical and physical environment on bacterial cells. Numerous methods have been tried, employing the total population number or rate of production is used in this investigation as an indication of population growth of Escherichia coli, Proteus morgani and Shigella sonnei. There has been infrequent mention in the literature of the employment of acid production as a measure of the growth rate of a bacterial culture. Porter (1946) and Wilson and Miles (1946) state that little data regarding the use of acid production is available, while Mond (1949) mentions that acid production may be used as an indication of growth. Application of this method of measuring growth is limited. Since scant study on acid production has been done, this investigation was undertaken as an attempt to determine what, if any, correlation exists between acid production from a fermentable sugar and growth rate