What is Methyl Red (MR) Test? The Methyl Red (MR) test is a biochemical test used in microbiology to identify and differentiate bacteria mainly among Enterobacteriaceae family. It is done to check the glucose fermentation pathway. It is used for detecting mixed-acid fermentation which produces stable acidic end products. In this test the organism is … Read more
What is Ames Test? Ames test is a rapid biological assay which is used to determine whether a chemical compound can cause genetic mutations. It was developed by Bruce Ames in 1970s. It is used as an early screening test for carcinogenic property because chemicals causing DNA mutation are frequently carcinogenic. It is based on … Read more
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.
What is Indole test? It is a biochemical test used in microbiology to determine the bacteria is producing enzyme tryptophanase. This enzyme help in breaking down amino acid tryptophan. This process occurs when bacteria having tryptophanase utilize tryptophan and the end products is formed. These are indole pyruvic acid and ammonia. In this test bacteria … Read more
Hippurate Hydrolysis Test is a biochemical test used for detecting the enzyme hippuricase(hippurate hydrolase) in microorganism. It is used for checking whether the organism can hydrolyze sodium hippurate or not. This process occurs when bacteria having hippuricase is exposed to sodium hippurate. The substrate is hydrolyzed and two end products is formed. The reaction is … Read more
What is Coliform Presence/Absence Test? Coliform Presence/Absence (P-A) test is a rapid simple and inexpensive qualitative method which is used mainly for monitoring treated drinking water and distribution system for fecal indicator bacteria (coliforms). It is the modification of traditional multiple-tube fermentation technique where a single large water sample volume is inoculated in one culture … Read more
BOD test (Biochemical Oxygen Demand) is a standard laboratory test. It is used for measuring the amount of dissolved oxygen which is consumed by aerobic microorganisms (bacteria) when the organic matter present in water sample is broken down and decomposed. It is the process where oxygen is utilized during biodegradation and this is referred to … Read more
COD Test (Chemical Oxygen Demand test) is a water quality test. It is used to determine the amount of oxygen required to chemically oxidize the organic and inorganic pollutants present in a water sample. It is based on oxidation of pollutants by a strong chemical oxidant. Generally potassium dichromate (K2Cr2O7) is used in heated and … Read more
What is a Glucose Tolerance Test? Glucose Tolerance Test (GTT) is a medical test which is used to measure how effectively the body processes the glucose (sugar) from blood into the tissues. It is most commonly performed as Oral Glucose Tolerance Test (OGTT). It is mainly used for diagnosis of metabolic conditions like prediabetes type … Read more
Membrane filtration method is a laboratory method which is used for estimation of microbial load (bioburden) in liquid sample like drinking water environmental water and pharmaceutical solution. It is a quantitative method and the bacteria are concentrated on a membrane filter and then counted as colony forming unit (CFU). Principle of this method is based … Read more
