Birby Bauer Disc Diffusion Report

Microchemlab.com states that a zone of inhibition is a qualitative method used clinically to measure antibiotic resistance and industrially to test the ability of solids and textiles to inhibit microbial growth. Researchers who develop antimicrobial textiles, surfaces, and liquids use this test as a quick and easy way to measure and compare levels of inhibitory activity (“Zone of Inhibition Test for Antimicrobial Activity”). The control of the experiment is distilled water. The independent variable is the different house cleaning products, and the dependant variable is the amount of growth or decline in the bacteria. Time, temperature, and amount of household household item are all constants in this experiment. Time needs to remain the same for all the products because time affects how well the bacteria grows. The temperature is required to stay the same as well because it can directly manipulate the rate of growth in the bacteria, and large amounts of the household item can offset the bacteria’s growth as

Gold standard procedures should be implemented with the aim of providing timely and accurate results. (Schentag) The culture result should be accompanied by its clinical significance, selective reporting of susceptibility testing results in accordance with hospital antimicrobial therapy guidelines and suggested management. (Schentag) This encourages appropriate prescribing and minimises unnecessary use of antimicrobials. The clinical microbiology team should also provide reports to AMS regarding resistant organisms.

The Diffusion and Osmosis Lab determines the molarities of various sucrose solutions based on change in mass. Using table sugar in different amount of molar concentration 0.0M, 0.2M, 0.4M, 0.6M, 0.8M and 1.0M. The molarity of the solution of the sucrose solution in the dialysis tubing determines the amount of water that either move into the bag or out the bag, which also means its mass changed.

Modern-day advances have allowed scientists to develop methods to control pathogens. The more common methods include the use of antiseptics, antibiotics, and vaccines. By definition, antiseptics are chemicals used to kill pathogens. A few widespread antiseptics include soap, vinegar, and rubbing alcohol. Antiseptics are primarily used for the external destruction of pathogens, while antibiotics and vaccines target internal pathogens. Nevertheless, there are and can be difficulties concerning the use of antibiotics. “As antibiotic use has become more common, antibiotic-resistant bacteria have evolved.” This resistance due to evolution is called antibiotic resistance. It results in the antibiotics having no effect whatsoever on the bacteria, rendering the antibiotics useless. When antibiotic resistance occurs, scientists must resume their search to create a new medicine to can kill the mutant bacteria.

2. Which antibiotic was most effective in killing the bacterial lawn on each plate? Which was the least effective?

This is important in the medical field because identification of unknown bacteria can help treat a patient by knowing the contributing source of a disease. Also knowledge of different bacteria helped others make antibiotics used today. This lab was completed by using the methods learned thus far in identification of bacteria.

The antibiotics will have different zones of inhibition on different bacteria. Also, a range of concentrations of the nutrients in the bacteria will change the bacterial growth.

Abstract-The gram-negative bacteria Serratia marcescens has gained attention in recent years for its tendency to cause nosocomial infections in humans, as well as its development of antibiotic resistance. Antibiotic resistance in a bacterium that is harmful to humans can be concerning as it can result in infections that are difficult to treat. In order to find out more about the growing antibiotic resistance of S. marcescens, this experiment used the disc diffusion method to test the susceptibility of S. marcescens to two varieties of antibiotics that were known to have success against some gram-negative bacterium: streptomycin and ampicillin. These antibiotics were, respectively, an aminoglycoside and a beta-lactam. The experiment tested which of the two that S. marcescens had developed more of a resistance to. The zones of inhibition of the discs were significantly larger for discs treated with streptomycin compared to discs treated with ampicillin. This led to the conclusion that S. marcescens is less resistant to streptomycin than to ampicillin.

When investigating this experiment I found many different types of antiseptics all with different effects on bacteria and the effectiveness of all these antiseptics varied. I found

5.) Inoculate the plate with a lawn coverage streak and place 1 bacitracin antibiotic disk in the

E.coli outbreaks have steadily grown over the last few decades. An expansion in big farming has led to E. coli not only being found in meat, but vegetation as well, due to waste runoff. This has increased our need for adequate antibiotics that can fight bacteria, like E. coli. The best way to pinpoint which antibiotics work is by measuring their ability to create antimicrobial agents or zones of inhibition. When a paper disc that has been saturated in an antibiotic is inserted in a solution of E.coli and medium, the zone of inhibition will be noted as the clear ring that forms around the disk. The antibiotics efficacy is then determined by measuring each disk zone of inhibition, and comparing these measurements to the zone measurements of an untreated specimen. If an antibiotic is to be deemed sufficient for treating E. coli it should show a zone of inhibition that is at least double the size of the untreated specimen.

Physicians perform gram stains before prescribing an antibiotic to know if the cell wall type and the antibiotic sensitivity link.

The Kirby- Bauer method is used to test antibiotics sensitivity to the microbe. Some antibiotics have broad-spectrum effect, which means they inhibit the growth of more than one microbe; while narrow spectrum only have an effective on one group of microbe. In order for this test to be effective a lawn of bacteria has to be made on Mueller- Hinton agar. This agar does two amazing things in the world of science. It contains a starch that makes it test plate transparent (easy to read results) and it control the rate of diffusion of the tested drug. Ampicillin, Gentamicin, Gentamicin, penicillin, and vancomycin are the fours types of antibiotics that were use to test the sensitivity of the microbe to them. The microbe was resistant to Ampicillin;

The main objective of this experiment is to investigate the effect of different types of antibiotics on bacteria Bacillus subtilis and Escherichia coli. Some of the main methods used in this experiment

What is your conclusion with regard to the effect of the drug on curing the infection? What is the odds ratio using the CMH method?