7 min read 
Test Name Acetate Utilization Test Detection Differentiate species based on ability to utilise acetate as the sole source of carbon. Typically used to distinguish Shigella spp. from Escherichia coli. Test organism It is best to use an acetate utilisation test to tell Shigella spp. from Escherichia coli. Test isolates are Gram-negative rods that don’t ferment … Read more
20 min read 
What is Methyl Red (MR) Test? Objectives of Methyl Red (MR) Test The objectives of the Methyl Red (MR) Test can be outlined as follows: Principle of Methyl Red test The principle of the Methyl Red (MR) test is based on assessing the ability of an organism to produce and maintain stable acid end products through … Read more
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What is Nylander’s Test? Nylander’s Test, a renowned chemical assay, is primarily employed to ascertain the presence of reducing sugars within a given sample. Reducing sugars, as the name suggests, possess the inherent ability to act as reducing agents. Therefore, when these sugars, such as fructose and glucose, are subjected to alkaline conditions, they can … Read more
17 min read 
What is Ames Test? Definition of Ames Test The Ames test is a biological assay developed by Bruce Ames, used to assess the mutagenic potential of chemical compounds by observing their ability to induce mutations in specific strains of bacteria, primarily Salmonella typhimurium. A positive result indicates that the chemical may be mutagenic and potentially … Read more
23 min read 
In 1898, Voges as well as Proskauer (16)characterized the process of fermentation of sugars by a variety of bacteria. They demonstrated that the gas that was produced during the process was a mixture of H2 and CO2 that when they added KOH to the cultures been grown in glucose peptone medium to allow for a prolonged period of incubation in presence of oxygen certain organisms developed a red fluorescent color. While the exact nature of the color was not known in the early days, this technique was suggested to differentiate between the bacterial strains that produced it and ones that didn’t. in 1906 Arthur Harden analyzed the fermentation products of Enterobacter aerogenes. He discovered that when it was surrounded by glucose, the organism made two compounds, acetoin as well as 2,3-butanedio.
20 min read 
What is Spot Indole Test? Definition of Spot Indole Test The Spot Indole Test is a rapid biochemical method used to detect the production of indole by bacteria, indicating their ability to metabolize the amino acid tryptophan. This test aids in differentiating specific bacterial species based on their tryptophan degradation capabilities. Objectives of Spot Indole Test … Read more
21 min read 
What is Indole test? Indole Test Definition The indole test is a biochemical assay used to determine a bacterium’s ability to metabolize tryptophan into indole through the action of the enzyme tryptophanase, aiding in the differentiation and identification of certain bacterial species. Purpose of Indol Test (Objectives of Indole Test) The indole test serves a … Read more
8 min read 
Purpose of Hippurate Hydrolysis Test Principle of Hippurate Hydrolysis Test Hippurate → Glycine + Benzoic acid Glycine + Ninhydrin → purple-colored complex Composition of Hippurate Hydrolysis Broth Ingredients Gms / Litre HI powder# 10.000 Peptone 10.000 Sodium chloride 5.000 Sodium hippurate 10.000 Final pH ( at 25°C) 7.4±0.2 Equivalent to Heart infusion powder Preparation of … Read more
21 min read 
Location of Fructolysis Why does fructose metabolism or fructolysis occur in liver cells? Properties and Sources of Fructose Absorption of Fructose From Fructose to Fat/Fructolysis/fructose metabolism pathway Steps of fructose metabolism pathway 1. Step 1 2. Step 2 3. Step 3A Metabolic Pathway Notes: At this point, the liver cell can use the same steps … Read more
6 min read 
What is Presence/Absence Test? Principle of Presence/Absence Test Objective of Presence/Absence Test PA Broth Preparation Composition Ingredients Gms / Litre Peptic digest of animal tissue 5.000 Tryptose 9.830 Beef extract 3.000 Lactose 7.460 Sodium chloride 2.460 Dipotassium phosphate 1.350 Monopotassium phosphate 1.350 Sodium lauryl sulphate 0.050 Bromo cresol purple 0.0085 Final pH ( at 25°C) … Read more