The Effects Of Bacteria And Its Effects On The Environment

1456 WordsMay 1, 20176 Pages
Introduction Bacteria are important microorganisms because they are used by humans for many reasons (Goel, 2014). For example, they are being use in the production of food such as cheese and vinegar; production of medical substances such as drugs; biotechnology, etcetera (Goel, 2014). Thus, such bacteria have to be mass produced to be exploited for many purposes in the industry (Goel, 2014). Batch culture, a closed system with limited supply of nutrients for growth, is commonly used for large-scale production of microorganisms (Hall, et al., 2014; Maier, 2009). This suggest that with the accumulation of toxic waste products, changing pH, oxygen tension, and decreasing supply of nutrients, cell growth will be inhibited and the culture will…show more content…
Finally, bacteria cells enter the death phase as death rate exceeds growth rate (Hall, et al., 2014; Maier, 2009). The knowledge of the patterns of growth under specified conditions for any types of bacteria is necessary for large scale production of cheese, drugs, etcetera (Goel, 2014; Maier, 2009). Aim Thus, the aim of the experiment is to show the typical phases of growth of a bacterial population, Vibrio natriegens, as well as the calculation of the generation time. Also, this experiment aims to determine how the availability of oxygen affects the growth of a bacterial population, Vibrio natriegens. The population density will be determined turbidometrically. Materials and Methods 12 ml of Vibrio natriegens culture was added to 200 ml of BHI medium contained in a pre-warmed flask (either shaking, aerated, or non-shaking, non-aerated) in a water bath at 37°C. 2 ml of samples of the cultures were removed after inoculation and at 10 min intervals for approximately 2 hours for measurement of turbidity by Optical Density (OD) at 590 nm. OD readings were recorded and plotted using log scale (ordinate) against time after inoculation (abscissa). The mean generation time () and mean growth rate (g) were calculated using the following equations respectively: and . Results To plot the growth curve of Vibrio natriegens under aerated or non-aerated condition, 12 ml of Vibrio natriegens culture was first
Open Document