In the experiment, the bacteria- E. coli were placed in two different sets of mediums – Brain-Heart Infusion (BHI) Broth & Nutrient Broth. The mediums were then set in different conditions (i.e. incubated or room temperature). Two methods were then used to determine the generation time of the E. coli: 1) The Direct Method 2) Indirect Method. By measuring the rate of growth of E. coli one can determine which is the best set of conditions for optimal growth of the species E. coli. For the cultivation of E. coli in the room temperature Brain-Heart Infusion (BHI) Broth the generation time that was determined using the Direct Method was 56.26 and by the Indirect method was 80 minutes. For the cultivation of E. coli in the incubated Brain-Heart Infusion (BHI) Broth the generation time that was determined the Direct Method was 23.15 minutes and by the Indirect method was 32 minutes. For the cultivation of E. coli in the incubated Nutrient Broth the generation time that was determined the Direct Method was 33.44 minutes and by the Indirect method was 38 minutes. From these results, it was determined that E. Coli's optimal growth was in the incubated Brain-Heart Infusion (BHI) Broth. The reason for this is that BHI is a highly nutritious infusion medium recommended for the cultivation of fastidious organisms (i.e. E. coli) and prefers warmer temperatures for cultivation.
             Within their natural environment, bacteria go through periods of rapid growth when nutrients are plentiful and when conditions for growth are favorable, but slow growth occurs as nutrients become limited and conditions for growth are not favorable. The transitions between these two states can be mimicked in the laboratory by growth of bacteria in batch culture. The growth of bacteria refers to the increase in the number of cells in that population where as the generation time is the time that it takes for a cell to divide to produce two new daughter cells. After ...