Kirby -Bauer Assay
Abstract:
In this Experiment, antibiotics will be applied to the bacteria to find out which antibiotic will be most effective in controlling the growth of the bacteria by comparing it to the control group.
Introduction:
This lab will help figure out which antibiotic is most effective in hindering the bacterial growth by measuring the zones of inhibition. The antibiotic that creates the greatest zone of inhibition is the most effective antibiotic in controlling bacterial growth. To show this, the experimental groups, which receive the treatment of the different antibiotics, will later be compared to the control group, and whichever antibiotic shows the greatest zone of inhibition will be the most effective.
Hypothesis:
…show more content…
Clean the work area effectively.
2. Obtain three TSA plates and label as in video.
3. Obtain an inoculate plate and observe the different colonies growing on the plate and record your observations. Note their appearance and other features.
4. Choose one bacterial colony for experiment.
5. Follow the procedure for the experiment as shown in the video make bacterial lawn on the plates and allow to site for a few minutes.
6. Label the quadrants on the media containing half of the petri dish and apply a single antibiotic disc in each of the three test areas and a blank in the fourth. Each of the Kirby-Bauer plates should have one disc of each antibiotic on it.
7. Seal the plates and place them in the designated area for the GTA to collect and incubate at 28 C for 24 hours. GTA will place plates in refrigerator to halt further bacterial growth.
8. Dispose of plates and other materials and directed by instructor.
Week 2
1. Clean the work area properly with sanitizers.
2. Measure the zones of inhibition for each antibiotic and record the data in notebook.
3. Compare results to the guidelines in Table 1. These standardized values indicate whether the bacteria is resistant, intermediately susceptible, or fully susceptible to the antibiotic based on the size of the zone of
...imary stain and not pick up the counterstain. Other human errors could have affected the results such as not inverting the plate before putting it into incubation would not allow for bacterial growth. Not pipetting the tube up and down to mix the bacteria that settled at the bottom of the tube before starting the Gram Stain would not allow for an accurate reading because there wouldn’t be many bacteria on the slide. Passing the slide over the bunsen burner too many times, hence killing the bacteria and not allowing for a Gram Stain. If this experiment had to be redone, one improvement would be to allow for more that one plate without a point deduction. Unexpected human errors might interfere with person’s results. Having more than one plate will allow for more accuracy in the results or allow for a person to determine were they went wrong during the experiment.
Bauer AW, Kirby WMM, Sherris JC, Turck M (1966) Antibiotic Susceptibility Testing by a Standardized Single Disk Method. Am J Clin Pathol. 45:493–496.
The purpose of the study is to identify an unknown microorganism using multiple microbiology lab techniques. Through this process I will gain knowledge on how to perform these techniques as well as the importance of these tests on identifying unknown microorganisms. This is significant as the goal of this course is to familiarize ourselves with the common microbiology tests as well as the microorganisms we encounter in our daily activities.
After the addition of the media, we insert an aeration tube inside and cover the lid with a cotton plug and start giving them aeration. This preparation has to be put on for 3 days under proper sunlight and 25-30 degree Celsius to observe if the culture is healthy/ potent or not depending on the color each culture portrays (The nanochloropsis culture should have a grass-green color to be seen as potent and the isochrysis culture should have a dark brown color to be seen as potent), if the colors seem dull and light, then that might mean that the culture is impotent.
Kanamycin antibiotics must be further improve so that in the future, more stronger bacteria with more strains can be eliminated but the concentration of the active pharmaceutical ingredients must be controlled so that it will not exceed certain concentration that leads to harmful side effects on the consumer.
Inconsistencies in this lab could have caused variations in data collecting. Collecting data from one petri dish was challenging because something could have been different on other petri dishes if this experiment was tested on several petri dishes. This could have been different because the other petri dishes could have had more micro-organisms in Section 2 instead of Section 1, or no bacteria could have grown at all in every section of the petri dish.- Second, nothing grew in section B even though there were no disinfectants in that section. The reason why the bacteria and mold might have grown in sections 1, 2, and 3 was because in the process of making the experiment, the coffee filter papers were touched with glove free hands and were not clean. If this lab was run again, some changes would be to wear rubber gloves, do not pour the hand sanitizers on the coffee filter paper but just pour one pump straight into the petri dish, have more than one petri dish to collect data off of, and check when the last time someone cleaned the door knob
The first step of the experiment that occurred is to take the two microcentrifuge tubes and label the first +pGLO and the second –pGLO. Next the micropipetter was set to 250 microliters and 250 microliters of calcium chloride was added to each microcentrifuge tube, using a fresh tip if it came into contact with the solution, then the tubes were put on ice until the bacterial was obtained. Next our group placed an E.coli colony into each of the tubes using a sterile loop and spinning the loop so that the bacteria was all in the solution, be sure to use a different sterile loop for each tube. Then we took a third clean sterile loop and placed it into the solution of the desired
Compounding all of these solutions, the pharmaceutical industry needs to conduct extensive research on developing new antibiotics for various pathogenic bacteria by studying the bacterial structure. This will help scientists to formulate ways of counteracting the functions of the various constituents of bacteria.
Antibiotics are powerful substances which are capable of inhibiting bacterial growth. Antibiotics can be consumed from any part of the body. Essentially there are two different types of antibiotics which perform different operations to the body. (Medical News, 1) The first discovered type is bactericidal, which not only inhibits but initially eliminates the bacterial or microbial organisms, this is done through exterminating the bacterium cell wall which furthermore erupts and causes the bacteria to be killed. The second type is bacteriostatic, as the name states. It aids to inhibit and limit bacterial growth. The antibiotic stops bacterial growth through stopping the process of protein synthesis, or bacterial reproduction. It is consumed to stop the growth of a microorganism permanently or temporarily. (Scientific American, 3) Patients consume antibiotics through the mouth. Antibiotics can also be directly injected into the body. Others can be applied on the infected area of the body, and physically cured or eliminated. (Medical News, 1)
The medication of paracetamol can be administered in various ways and they are sold in different formulations. The common dosage comes in tablets form of 500 mg, in dispersible fizzy tablets (500 mg) and oral suspensions. It can also be bought in capsules as a mixture with other API like caffeine and codeine.
Bacteria can be prevented from growing and/or living with the use of antibiotics. Antibiotics combat bacteria several ways by preventing the cell wall from developing properly, protein synthesis hindrance, interferes with deoxyribonucleic acid (DNA) production by impeding cell division, interfering with outer-membrane and plasma function, killing the cell (Aziz, 2013).
6. Unscrew cap on Penicilium italicum culture tube with one hand and flame the mouth of the tube.
4. Put milk samples into the beaker for about five and a half minutes and take samples out after time is up. 5. With the warm samples, open the pouch containing the gel cassette and remove the cassette.
The discovery of antibiotics is attributed to Alexander Fleming who discovered the first antibiotic to be commercially used (Penicillin) in approximately 1928. An antibiotic, also known as an antimicrobial, is a medication that is taken in order to either destroy or slow the growth rate of bacteria. Antibiotics are integral to the success of many medical practises, such as; surgical procedures, organ transplants, the treatment of cancer and the treatment of the critically ill. (Ramanan Laxminarayan, 2013)