Catalase Test Lab Report
For the Catalase test, the use of hydrogen preoxide on the sample of the unknown …show more content…
The three medium are sulfur reduction, indole production and motility. For sufur reduction, the unknown bacteria was able to reduce sulfur to hydrogen sulfide. There was a positive result for this part of the test. There were black precipitate which is a sign for a positive result. For motililty, It also test positive by the cloudy red result of the medium. The last part of the test is indole. This test the microoganism be able to produce tryptochan . The bacteria also test positive for this part of the medium.For the urease broth medium, the bacteria test positive for urease. The positive result is when the organism turn pink. The pH indictor for this test is phenol red. Phenol red turn yellow in a acidic enviroment and pink is alkaline enviornment. This test is useful for enterics bacteria like the genus Proteus.
Unknown bacteria #20 has the following results: Catalase positive, MSA negative, Nutrient gelatin negative, nitrate reduction positive, SIM positive, and Urease positive. After review these results, the unknown was determing to be Proteus. Vulgaris. The tests that help confirm the result was SIM medium , nitrate reduction meduim and urease broth. After research the internet for the reason why gelatin test was negative, Proteus vulgaris take a long time to break down gelatin. Therefore the test was a negative because there was not enough time for it to become a