Testing Antibiotics on Our Unknown {Labs 10 and 11 - May 26 and 27, 2015}

     For this test, I inoculated our unknown bacteria onto an agar plate, then placed five different antibiotics onto the plate to see if any of them would inhibit the growth of our bacteria. 

The chart to determine
susceptibility and resistance

Materials:

• Agar Plate
• Unknown bacteria
• Penicillin disk
• Tetracyclin disk
• Streptomycin disk
• Erythromycin disk
• Novobiocin disk
• Ethanol in a beaker
• Tweezers
• Gloves

Our Unknown bacteria
and the Antibiotics

Procedure:

     I began by preparing the agar plate by inoculating our bacteria. I then labeled the bottom of the agar plate with the different antibiotics that I would be testing. After labeling, I sterilized the tweezers and placed the first antibiotic disk onto the agar plate. I sterilized the tweezers between each disk. After placing all five antibiotic disks onto the plate, I incubated the plate for 24 hrs. 

 The next day, I retrieved the plate and documented the results. Our unknown bacteria is resistant to penicillin(1), Erythromycin(4), and Novobiocin(5). However, it was susceptible to both Tetracyclin(2) and Streptomycin(3).