Esscherichia Coi Case Study

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Effect of different cleaning products of the growth of K12 strain Escherichia Coli?

Which household cleaning product (hydrogen peroxide, Pine-sol, Clorox Bleach, Mr Clean antibacterial liquid cleaner) is the best inhibitor of K12 Escherichia coli (E. coli) growth? The manipulated variable was the cleaning product or disinfectant on used of the Whatman antibiotic assay paper disc. The dependent variable is the zone of inhibition of the prokaryotic bacteria E. coli. In topic one IB requires that we learn about Eubacteria, traditional bacteria that are typically pathogenic, E. coli fall into this category. We also had to learn about Florey and Chain experiments, which is where I learned about zones of inhibition. The problem interests me because
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Coli is a commonly found bacteria in the environment, food, and the intestines of human and animals. Most strains are harmless, but some strain can make humans sick, food poisoning, diarrhea, urinary tract infections and respiratory illnesses.
E. coli K12 strain is not known for any harmful effects. The K12 is considered preferable because it has a more rapid and consistent growth. IB requires that you cannot grow bacteria at Room temperature. E. coli grow best at 37 degrees Celsius so that is the temperature I will grow it at in the incubator.

Hydrogen peroxide, H2O2, is sold to consumers in 3% to 6% concentration in water. When bacteria cause the immune system to activate specific cells produce large amounts of Hydrogen peroxide to fight the infection. It is a disinfectant and an
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Identify each quadrant with a letter that designated what I placed there. Using sterile technique I removed the plug from the E. coli broth culture. I then heated the mouth of the test tube with the alcohol burner.
I dipped the cotton swab into the broth culture. While I was still holding the swab and plug in one hand, I reheated the mouth of the broth test tube. I replaced the plug in the test tube. I lifted the Petri dish cover slightly. I started at the top, swiping the cotton swab across the entire agar surface. I used a back and forth motion to ensure that the entire surface has been covered with broth culture. Next I turned the dish a quarter turn and re-swiped the swab across the agar surface.
I replaced the cover of the petri dish. Dispose of the swab by first burning the end and then placing it in the designated disposal ben. I used a sterile forceps to place each disk in the center of a separate quarter of agar. Press each disk lightly onto the agar. I put the cover back on the petri dish and I incubated for 72 hours. I then measured the zone of inhibition with a ruler that measured to the nearest mm. I need to make sure I follow proper aseptic

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