Friday, September 27, 2019

Staphylococcus and streptococcus Lab Report Example | Topics and Well Written Essays - 1000 words

Staphylococcus and streptococcus - Lab Report Example Botulinum, C.Perfringen among others and Staphylococcus spp and streptococcus spp. Bacillus spp are typical endospore, competent naturally, gram-positive, aerobic or facultative aerobic bacilli .Rode shaped. These tests have been explored in the next section. Results Gram staining Commonly, Gram staining is technique employed in the two broad groups of bacteria differentiation and it’s based on the different constituents of the bacteria cell wall. The technique is able to distinguish between Gram negative and Gram positive bacteria groups by red or violet coloring of the cells. Violet staining indicate Gram positive bacteria because of a thick layer of peptidoglycan presence in the bacteria cell walls, hence the crystal violet is retained by these stained cells. On the other hand, red staining, indicate Gram negative bacteria and this is due to a thinner peptidoglycan wall that never retains the crystal violet during the process of discoloring. In the test the bacteria were Gr am positive, the primary stain was retained and the secondary stain was lost resulting to violate appearance after viewing under a microscope. Culturing The incubation was both with incubation on agar and broth media at a temperature of 37 oc and 25 oc Techniques A spec ­i ­men loop was got then streaked on one sec ­tion, flamed and cool, later turned at 45o then streaked for a 2nd time, that over ­lap ­ped the first streak.   It was repeated for third and fourth time.   Iso ­lated regions were got in the third region with large growth amount, irregular growth form and with elevated colony. Incubation temperature was at 37 oc. When this isolate was grown on agar plate at 37 oc, there was a lot of growth with dark colored colonies; growth form was circular, with flat, filamentous margin. Alternatively when it was grown on agar at 25 oc, the amount of growth was spread out, growth form was irregular and flat, and margin was flat. Growth in broth media at 37 oc the amou nt of growth was that there was a membrane on top of the broth; growth pattern was aerobe with oxygen on top. But in broth media at 25 oc there was no growth seen. Biochemical tests: Carbohydrate Fermentation   Ã‚   Some bacteria identification is aided by identifying the type of nutrients it can utilize as well as the type of end products in the process that will be produced. These characteristics are regulated by the bacteria enzymes produced. Furthermore, this enzymes produced are genetically regulated, the sugars pattern fermented may be unique to a specific strain or species. The products of fermentation are normally acid such as acetic acid, lactic acid, etc, neutral such as ethyl alcohol etc, or gases like hydrogen, carbon dioxide, etc. In the experiment, the determination of the sugar fermentation products of the unknown organism given was by first preparation of carbohydrate fermentation broth at pH 7.4. The broth contained any of the following essential ingredients: 0.5% to 1.0% of the carbohydrate to be tested that included lactose, glucose, Sucrose maltose and starch, nutrient broth and the phenol red pH indicator. The light red color nutrient broth is able to support most organisms’ growth regardless of being able to ferment sugar or not. The unknown test organism was inoculated into a broth having the mentioned above test sugar then later incubated. Production of enough acid products was indicated by a bright

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