This experiment has been conducted to accumulate data on the growth of Escherichia coli (E. coli) and to monitor how it grows under certain conditions. It has been demonstrated that the levels of glucose and dissolved oxygen were found to affect the rate of growth of E. coli proportionally with a lack of oxygen resulting in the lowering of the pH. In this experiment the growth of E. coli was studied at constant temperature (37 0C) at which it grows ideally. Experimental results for the growth of Escherichia coli showed good agreement with theory. Introduction
An Escherichia coli is a rod-shaped bacterium measuring about 2.5µm by 0.5µm.It is found in the guts of vertebrates. E. coli is a normal resident of the human colon and therefore grows ideally at 37 0C. In fact, the presence of most strains of E. coli keeps other more harmful bacteria away by starving them of food. They also help to make vitamin K which is an important vitamin for blood clotting. In some cases, E. coli infection can …show more content…
In the batch reactor the concentration of glucose decreased from certain amount to o g/L within first 4 hours of the process. However, the fermentation cell yield coefficient could be improved by using fed batch reactor, in which the substrate (i.e., glucose) is added into the mixture at desired times. The level of dissolved oxygen (DO2) was also one of the major factors that affect the fermentation cell yield coefficient. The decrease in the amount of DO2 supplied prevents E. coli from continuing to increase exponentially. If DO2 was provided continuously it would prevent the cells from respiring anaerobically and producing acetic acid. The growth of the cells was inhibited by the acetic acid which lowers the pH, so the fermentation cell yield could be raised by preventing this from