October 18th, 2011
Today I inoculated 7 tubes for 7 separate tests. I made a zig-zag streak when I punctured the agar slant for the TSI test, and regular inoculations for the litmus milk, glucose, sucrose, lactose, gelatin, and methyl red tests. I stored them in the incubator and then the whole lab performed an experiment to confirm whether our bacteria was an aerobe or not by pouring hydrogen peroxide on a plate containing bacteria. Mine reacted to the hydrogen peroxide which confirms that my bacteria are aerobic.
Hydrogen Peroxide Test
October 19th, 2011
Checking up on the tests, I found that there was a lot of growth in the TSI tube, but not much seemed to happen with the other tubes. I decided to check again tomorrow.
October 20th, 2011
I checked the tubes again today, and the TSI test, despite having growth, was a negative test. The litmus milk was turning blue at the top, indicating a possible alkaline pH. The gelatin went from solid to liquid, but when refrigerated it became solid again, making it negative for gelatinase. When 10 drops of methyl red was added to MR-VT test (after adding 15 drops of alphanapthol and 5 drops of KOH), it change into a gold color, testing negative for mixed fermentation. There also was no fermentation in the glucose and lactose fermentation but a small bubble was found in the sucrose tube which indicated a positive fermentation.
Litmus Milk
Adding Methyl Red
Gelatin
