The spectrophotometer measures the absorption and spectral bandwidth of the given sample. Absorption is the logarithm of transmittance, i.e. Log (T), whereas transmittance is the portion of light moved through the sample. Transmittance refers to the ratio of light incidents on the test sample to the light transmits through the solution, i.e. IO/I. Spectral bandwidth …
Gluconeogenesis occurs in a reverse manner of glycolysis, which produces glucose by the precursors like pyruvate, lactate, glucogenic amino acids. It is sometimes called Neoglucogenesis. It is a ubiquitous or universal pathway, which occurs in humans, animals, plants, fungi and other living organisms. Gluconeogenesis has only three irreversible steps opposite the glycolysis pathway, while the …
Vermicomposting is a composting technique, which turns the organic debris into a humus-like product by employing earthworms. “Vermicompost” is the compost produced by the vermicomposting unit. The vermicompost merely refers to the earthworm’s excrement, which provides essential nutrients, aeration, porosity, structure, fertility and water-holding capacity to the soil and plant body. The vermicomposting method requires …
The bile solubility test is a biochemical test that distinguishes bile soluble and bile resistant α-haemolytic Streptococci. Streptococcus pneumoniae is the only strain that emulsifies by reacting with the bile solubility reagent, whereas the other α-haemolytic Streptococci do not undergo such reaction. The reason for the dissolution of the Streptococcus pneumoniae is due to the …
Urease test is an analytical method practised to identify the urease positive and negative organisms based on the production of cytosolic urease enzyme. It distinguishes the Proteus species from the non-lactose fermenting members belonging to the Enterobacteriaceae family. Urease test makes the use of urea base. Conventionally, Stuart formulated urea broth was used to identify …
The coagulase test is an analytical method that demarcates the staphylococci species into coagulase-positive and coagulase-negative species. Coagulase is an enzyme, which can either bound to the cell surface of bacteria as “Bound coagulase” or reside within the extracellular space as “Free coagulase”. Staphylococcus aureus, S. intermedius, S. hyicus are coagulase-positive organisms. Staphylococcus epidermis, S. saprophyticus, …
Oxidase test checks the production of cytochrome-c oxidases, whose presence in the test organism becomes evident by the formation of the blue-purple coloured complex (indophenols). It uses TMPD (tetramethyl phenylenediamine dihydrochloride) reagent. In an oxidized state, TMPD develops a blue-purple coloured complex while remains colourless in a reduced state. Therefore, we can say that the …
Catalase test is one of the biochemical analysis that generally comes into use in identifying the organisms (whether they are catalase producers or not). It is primarily used to distinguish between the two classes of gram-positive bacteria, namely Staphylococcus and Streptococcus species. Streptococcus bacteria are mostly facultative anaerobes (may produce catalase), while few are obligate …
Messenger RNA abbreviated as “m-RNA”, and it contains specific codons encoding particular amino acids, which later synthesize proteins (as amino acids are the monomer units of proteins). Protein is an element that is required to develop life forms, so a cell must translate specific proteins. Therefore, for proper growth and cell development, gene translation or …
Voges Proskauer test depends upon the formation of a neutral end product “Acetoin” in the MRVP media, which directly relies on the breakdown of glucose into an intermediate product, pyruvic acid. The pyruvic acid enters the butylene glycol pathway and produces an end product named acetyl methyl carbinol or acetoin. It is named after the …