Results from Nutritional & Motility Tests
Negative Starch TestStarch: Negative. After flooding the plate with Gram’s Iodine a colored area appeared around the growth of bacteria, which indicates a negative Starch test.
Negative Casein Test
Casein: Negative. The bacteria remained white after incubating which indicated a negative Casein test.
Gelatin: Positive. After incubating overnight, our semi-solid gelatin liquefied which indicates a positive Gelatin test.
Fat
Fat: The results were inconclusive; will incubate longer to determine positivity or negativity. We will return to this test.
Litmus Milk: Results inconclusive after one day; still incubating
Results of motility test: non-motile
Various Bacterial Tests
We then conducted ten more tests to further determine the identity of the unknown bacteria. The tests we performed were (1) Urea test, to test for the ability of bacteria to hydrolyze bacteria, (2) Nitrate test, to determine if the bacterium is able to reduce nitrate to ions to nitrite ions or nitrogen gas, (3) Triptone test, to determine the ability of the bacteria to split the amino acid Tritophan into Indole and Pyruvic acid, (4) MR/VP test, to determine the ability of bacteria to ferment glucose via mixed acid fermentation and butanediol fermentation, (5) TSIA test, to differentiate gram negative enteric bacilli and their ability to ferment glucose, lactose and sucrose, and to produce H2S, (6) Citrate test, to determine if a bacterium can utilize citrate as its sole source of carbon and energy, (7) Carbohydrate test (with sucrose, glucose, lactose and maltose), to determine the ability of some bacteria to ferment a particular carbohydrate.
For (1) Urea test, (2) Nitrate test, (3) Triptone test, (4) MR/VP test, (7) Carbohydrate test we, by using aseptic technique, inoculated the broth with our unknown bacteria. Each of these will be incubated at 37 degrees C for varying hours to days. The Carbohydrate tests consisted of four different test tubes: sucrose, glucose, lactose and maltose.
For (5) TSIA test we, by using aseptic technique, inoculated the semi-solid agar butt by stabbing the inoculating needle half depth and as we removed the needle we streaked a zigzag pattern along the surface of the slant. This will be incubated at 37 degrees C for 18-24 hours.
For (6) Citrate test we, by using aseptic technique, inoculated the citrate agar slant with a loop full of bacteria. This will be incubated at 37 degrees C for up to four days.
For (1) Urea test, (2) Nitrate test, (3) Triptone test, (4) MR/VP test, (7) Carbohydrate test we, by using aseptic technique, inoculated the broth with our unknown bacteria. Each of these will be incubated at 37 degrees C for varying hours to days. The Carbohydrate tests consisted of four different test tubes: sucrose, glucose, lactose and maltose.
For (5) TSIA test we, by using aseptic technique, inoculated the semi-solid agar butt by stabbing the inoculating needle half depth and as we removed the needle we streaked a zigzag pattern along the surface of the slant. This will be incubated at 37 degrees C for 18-24 hours.
For (6) Citrate test we, by using aseptic technique, inoculated the citrate agar slant with a loop full of bacteria. This will be incubated at 37 degrees C for up to four days.