Organisms Show Resistance To The Drug example essay topic
Create a bacterial lawn by a. Inoculate each dish with 0.2 mL of the appropriate bacteria. Deposit the inoculum in the center of the plate. b. Remove the spreading rod from the ethanol and ignite the ethanol (Do not leave the rod in the Bunsen burner flame longer than is needed to ignite the ethanol.) Allow the ethanol to burn off. Spread the culture over the entire surface of the plate using the sterilized spreading rod. Before continuing wait five minutes to allow the culture to be absorbed by the nutrient agar.
3. Apply antimicrobial disks to the plate using the dispensers as demonstrated by your instructor. Gently press the disks to the surface of the agar with a sterile set of forceps. 4. Incubate the Petri dishes for at least 24 hours at 37 degrees Celsius. 5.
Measure the diameter (in mm's) of region around the disks where growth was inhibited. This region will appear as a clear hallo around the disk and is known as the zone of inhibition. If no clear region is evident record the diameter of the disk itself. Record the zone of inhibition on the provided data sheet.
6. Using the sensitivity chart, determine if the organisms are sensitive, resistant, or fall into the intermediate zone. If an organism is sensitive to an antimicrobial drug that drug could be used to treat that organism. If it is resistant the drug will not work against that organism. If an organism falls in the intermediate zone the drug should only be used if no other option is available.
7. For each drug determine if it has a broad or narrow spectrum. If it is effective against both E. coli and's. aureus, the drug would be considered to be broad spectrum. If either or both organisms show resistance to the drug it is considered to have a narrow spectrum. Results In the results of our experiment we found that most of the antimicrobial's showed a narrow spectrum of activity to the microbes of E. coli and S. aureus.
Ceftizoxime, streptomycin and had a broad spectrum of activity to the microbes. The penicillin derivatives showed a narrow range of activity but also had the only resistance shown. The E. coli was resistant to both the Oxacillin and the Penicillin G. the S. aureus was totally eradicated by the penicillin derivatives and the. Discussion Finding a narrow spectrum of activity drug for the bacterial infection has a greater effect than that of a broad spectrum drug. Using a drug with an intermediate zone of inhibition may be used but it most likely would not be as successful.
If the proper drug is not found and used a microbe is more apt to become resistant to more drugs thus making it more difficult to treat the infection.