The DNase test is a differential biochemical test which is used to detect the ability of microorganism to produce an extracellular enzyme called deoxyribonuclease (DNase). It is the process where polymerized DNA present in the medium is hydrolyzed into smaller nucleotide fragments by the action of this enzyme. These degraded products can be absorbed by … Read more
It is a biochemical test used for the identification and differentiation of non-fermentative Gram-negative bacteria. It is mainly applied for the confirmation of Pseudomonas aeruginosa. This test is based on the ability of the organism to utilize acetamide as the sole source of carbon and nitrogen. The test medium contains acetamide and a pH indicator … Read more
The Casein Hydrolysis Test is a biochemical test that is used to determine the ability of microorganism to produce and secrete extracellular proteolytic enzyme known as caseinase. It is the process in which casein protein of milk is broken down into smaller soluble products. Casein is the main protein present in milk and it is … Read more
Gram-Sure Test is a rapid qualitative diagnostic test used for the differentiation of aerobic Gram-negative and Gram-positive bacteria. It is mainly applied for bacteria that are rods or coccobacilli in shape. This test works by detecting the presence of a specific enzyme known as L-alanine aminopeptidase. This enzyme is present almost exclusively in Gram-negative bacterial … Read more
The Esculin hydrolysis test is a biochemical test which is used for the identification and differentiation of certain bacteria, mainly Enterococcus species and Group D streptococci from other streptococci. It is also used for identifying some other organisms such as Listeria species and members of Bacteroides fragilis group. It is based on the ability of … Read more
It is a biochemical test used in microbiology for the identification of Streptococcus pneumoniae from other alpha hemolytic streptococci. It is mainly based on the ability of pneumococcal cells to undergo lysis in presence of bile salts. This test is commonly performed in diagnostic laboratories for confirmation of pneumococcal isolates. It is the process in … Read more
Leucine aminopeptidase (LAP) is an enzyme used to distinguish catalase-negative, gram-positive cocci of Aerococcus and Leuconostoc (LAP test negative) from other organisms in the group, such as Streptococcus, Enterococcus, Lactococcus, and Pediococcus (almost always positive).
It is a biochemical test that is used to determine the ability of microorganism to produce and secrete the enzyme lipase. It is also referred to as lipase test. The complex lipids such as triglycerides are large molecules and these cannot pass through the bacterial cell membrane. Due to this reason some bacteria releases the … Read more
Ouchterlony Double Immunodiffusion Method is a qualitative immunological technique that is used to study antigen–antibody reaction in vitro. It is the process in which both antigen and antibody are allowed to diffuse freely in a semi-solid medium usually agar or agarose gel. This method was developed by Örjan Ouchterlony and it is commonly used for … Read more
The Arneth count is a hematological method used for the classification of neutrophils based on the number of lobes present in the nucleus. It is the process in which neutrophils are grouped into different classes according to nuclear segmentation and this helps in understanding the age and functional status of the cells. In this method … Read more
