Growth Dynamics Of E. Coli In Varying Concentrations Of Nutrient Broth :: essays research papers

Growth Dynamics of E. coli in Varying Concentrations of Nutrient Broths, pH, andin the Presence of an AntibioticAbstractThe single-valued function in this experiment of ripening dynamics of E. coli in varying mediawas to construe which media produces the maximum number of cells per unit time.First a control was ceremonious for E. coli in a 1.0x nutritive broth. This wasused to comp be the growth in the experimental media of 0.5x and 2.0x, nutrientbroths nutrient broths with an additional 5.0mM of glucose and another with5.0mM lactose nutrient broths of varying pH levels 6.0, 7.0, and 8.0 andfinally a nutrient broth in the presence of the drug/antibiotic chloramphenicol.A variety of OD readings were taken and calculations made to determine thenumber of cells present after a given over time. Then two graphs were plotted, Numberof cells per unit volume versus Time in minutes and logarithm of the number of cellsper unit volume versus Time growth submit. The final cell concentrat ion for thecontrol was 619,500 cells/mL. Four media, after calculations, produced lesscells than that of the control, these were Chloramphenicol producing 89,3 01cells/ml glucose producing 411,951 cells/mL lactose producing 477,441 cells/mLand finally pH 6.0 producing 579,557cells/mL. The remaining four media, aftercalculations, produced cell counts greater than the control 2X with 1,087,009cells/mL 0.5X with 2,205,026 cells/mL pH 8 with 3,583,750 cells/mL and finallypH 7.0 with 8,090,325 cells/mL. From these results the ratiocination can be madethat the environment is a controlling promoter in the growth dynamics of E. coli.This was found through the regulation of pH and nutrient concentrations. In thepresence of the drug/antibiotic, chloramphenicol, cell growth was minimal. excogitationE. coli grows and divides through asexual reproduction. Growth will continueuntil all nutrients are depleted and the wastes rise to a toxic level. This isdemonstrated by the Log of the number of cells per unit volume versus Timegrowth curve. This growth curve consists of four phases Lag, Exponential,Stationary, and finally Death. During the Lag phase there is little ontogenesis inthe number of cells. Rather, during this phase cells ontogenesis in size bytransporting nutrients inside the cell from the medium preparing forreproduction and synthesizing DNA and various enzymes undeniable for cell division.In the Exponential phase, also called the log growth phase, bacterial celldivision begins. The number of cells increases as an exponential function oftime. The terzetto phase, Stationary, is where the culture has reached a phaseduring which there is no net increase in the number of cells. During the