Biochemical tests are laboratory procedures that use specific chemical reactions to identify and characterize microorganisms, such as bacteria. These tests are often used to identify the presence of specific enzymes or metabolic pathways in a microorganism, which can help to distinguish it from other microorganisms.
Some common biochemical tests used in bacteriology include:
Oxidase test: This test is used to detect the presence of the enzyme cytochrome oxidase, which is involved in the metabolism of oxygen.
Catalase test: This test is used to detect the presence of the enzyme catalase, which helps to break down hydrogen peroxide.
Indole test: This test is used to detect the presence of the enzyme tryptophanase, which breaks down the amino acid tryptophan.
Nitrate reduction test: This test is used to detect the ability of a microorganism to reduce nitrate to nitrite.
Gelatinase test: This test is used to detect the ability of a microorganism to produce the enzyme gelatinase, which breaks down gelatin.
These are just a few examples of the many different biochemical tests that are used in bacteriology. Biochemical tests can be useful for identifying and classifying bacteria, and for understanding their metabolism and ecological role.
7 min read 
Purpose Principle of MUG Test Requirements Quality control of MUG Test Using the following quality control organisms, all lot numbers of MUG Disk have been tested and found to be good. Control organisms should be tested using quality control methods that have already been set up in the lab. If there are problems with quality … Read more
6 min read 
Some bacteria make substances that other bacteria need to grow. The X factor and the V factor are two such substances. The heat-stable X-factor can be protoporphyrin IX, hemin, or other iron-containing porphyrins. It can be found in red blood cells and outside of them in the blood. The heat-sensitive V-factor may be nicotinamide adenine dinucleotide (NAD) or nicotinamide adenine dinucleotide phosphate (NADP), and it is mostly found inside red blood cells. The X and V factor test or a disc test can be used to find out if a bacterium depends on its X factor or its V factor. The results can help identify the bacteria.
5 min read 
Hopkin’s Cole/Adamkiewicz–Hopkins Test Definition Hopkins Cole Test also referred to as glyoxylic Acid Reaction is among the qualitative testing methods for determining the differences between different types of amino acids and proteins. The test is used to determine the presence of tryptophan, an amino acid, in proteins. Objectives of Hopkin’s Cole Test Principle of Hopkin’s … Read more
11 min read 
Starch Hydrolysis Test Objective Starch Hydrolysis test principle Starch is a polysaccharide that is composed by glucose subunits. The glucose rings may be joined by a 1,4-glucosidic glucosidic link, which results in long, straight chain of glucose. (“1, 4” is a reference to the bond formed between number 1 carbon in one glucose molecule, and … Read more
13 min read 
Decarboxylase Test Medium base is used to distinguish bacteria based on their ability to decarboxylate amino acids.
7 min read 
Lysine decarboxylase test relies on the capability of certain bacteria to degrade L-lysine into caverine after the release of carbon dioxide.
6 min read 
The MRS formulation was made by de Man, Rogosa, and Sharpe to replace a variable product (tomato juice) and give lactobacilli in general a good place to grow.
6 min read 
The SXT (sulfamethoxazole-trimethoprim) susceptibility test tells the difference between group A and B streptococci and other hemolytic streptococci.
5 min read 
Streptococcus pneumoniae can be distinguished from other viridans streptococci by showing that it is sensitive to optochin, dissolves in bile, reacts with a specific DNA probe, or has species-specific capsular polysaccharides.
7 min read 
The Bacitracin susceptibility test is one of the antimicrobial disc tests used to distinguish between group A and other -hemolytic Streptococci.