The Effect Of Concentration Of Glucose Tests On The Levels Essay

715 Words Apr 10th, 2015 3 Pages
Several tests were accomplished technically and carefully to identify the unknown # 230 to be M.luteus bacteria. Most of the observed results do match the expected ones, except two tests. The observed results for glucose fermentation and oxidase test did not match the expected results.
The expected result for fermentation of glucose test was negative while the observed result was positive. Conversely, in Kligler iron agar media, which exams the ability of bacteria to ferment lactose and glucose, M.Luteus gave negative outcome which matches the expected result. Thus, I repeated the Kligler iron agar to test if M.Luteus can ferment glucose and I obtained same result which is negative. Getting positive result for glucose in beginning could be due to environmental factors such as contamination or some Micrococci produce acid while growing aerobically on the glucose giving a false (+) result. Also, mismatch results as can be due technical problem such as change in pH, or improper inoculation of M.Luteus. Moreover, M.luteus gave a negative result for oxidase test while the expected result should be positive. Based on Bergey’s Manual and the Unknown Identification Flowcharts on blackboard, states “Oxidase test may be inaccurate positive for bright yellow specie,” [1] note that M.Luteus’s colonies has bright yellow color. Furthermore, the rest of observed tests results such as motility media and SIM both test motility did match expected consequences.
Micrococcus luteus was…

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