Distinguish between fermentation test tells you about the microbes you are study
ID: 206852 • Letter: D
Question
Distinguish between fermentation test tells you about the microbes you are studying 2. tests and respiration tests in terms of what each category of 3. Sketch a labeled, colored flow diagram for the nitrate test procedure, i including results at each step and how to interpret the results 4. In a situation similar to the practicum, what would you look for to state that a particular test is positive for mannose fermentation? Describe in detail. 5. In a situation similar to the practicum, what would you look for to state that a particular microbe is both oxidative and fermentative? Describe in detail. 10, F 16Explanation / Answer
Respiration is the process of breakdown of glucose inside the cells to release energy. It has been categorised into two types based on the availability of oxygen : 1] Aerobic respiration -- In this, the complete breakdown of glucose takes place giving out CO2, H20 and 38 molecules of ATP.
2] Anaerobic respiration -- As the name suggests, this takes place in the absence of O2 [ as in yeast ] or when very little O2 is present [ as in muscle cells after a heavy physical work] .
Fermentation is a type of anaerobic respiration. It is the metabolic pathway by which sugar is broken down in the absence of oxygen giving off organic acids, gases or alcohol.
It mostly occurs in yeast and bacteria and has an immense importance , not only in the food industry but also in breakdown of dead organic matter.
Yeast is the primary microbe used in the food industry. It produces CO2 gas and alcohol by fermenting sugar or carbohydrates. It has been used to produce alcoholic beverages since ancient times.
Anaerobic bacteria are also used in the food industry as well as for decomposing waste and obtaining the very useful methane gas [ in biogas plants ]
Milk turns into curd by the action of lactobacillus which converts lactose of milk into lactic acid.
So, to test various categories of microbes for respiration and fermentation, we can test for the presence of alcohol or acid as the end product.
3] NITRATE [NO3]
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[ Nitrate reductase]
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NITRITE [NO2]
[Nitrite reductase]
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NITRIC OXIDE [NO]
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[ Nitric oxide reductase]
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NITROUS OXIDE [N2O]
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[ Nitrous oxide reductase]
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NITROGEN [N2]
These are the steps for the Nitrate reduction test.
This test is performed for the differentiation of members of Enterobacteriase on the basis of their ability to produce Nitrate reductase enzyme that hydrolyse Nitrate [ NO3-] to Nitrite [NO2-] which may again be degraded to various nitrogen products like nitrogen oxide, nitrous oxide and ammonia [ NH3 depending on the enzyme system of the organism and the atmosphere in which it is growing.