Evaluation of growth of lactobacillus casei culture in semi

Abstract

Lactobacillus casei is a probiotic bacteria known to have excellent nutritional benefi ts and a health-promoting effect, specifi cally on the intestinal microfl ora. It has been demonstrated that it generates positive changes in pathogenic gastrointestinal diseases and
that it is resistant to wide ranges of pH and temperature; that is why when it is cultivated in the presence of oxygen (aerobic regime) it gives rise to the production of biomass, taking into account  the optimal environmental conditions for the bioprocess. With this motivation, through the present research, the growth of strains of the Lactobacillus casei species was evaluated in a biotechnological process of cultivation for laboratory scale production. The type of equipment used to carry out the process and produce in a semi-continuous way (“fed-batch”) was a bioreactor. For this purpose, the substrates were conditioned and the optimal concentrations to be used for biomass production were determined. The growth kinetics was  evaluated by means of the study of turbidimetry in the different substrates and growth tests were carried out on Den Manrogosa and Sharpe (MRS) agar and broth to determine the amount of colony forming units (CFU) in the different substrate concentrations. A software was created to simulate the process, and it was proven that it reproduced the behavior of the process.