Chromogenic Substrates

5-Bromo-4-chloro-3-indoxyl butyrate is a colorimetric substrate used to detect and quantify esterase activity. Upon hydrolysis by esterases, it yields a blue-green dye, allowing the detection and quantification of enzyme activity. It is commonly used in assays for the screening of esterase-producing microorganisms and in research aimed at understanding the role of esterases in various cellular processes.

2-Chloro-4-nitrophenyl a-D-maltotrioside (2CNP) is a potent hypoglycemic agent that has been shown to decrease postprandial blood glucose levels in humans. 2CNP is a white crystalline solid that is soluble in water and ethanol. The transfer reactions of 2CNP are enhanced by benzalkonium chloride, which forms an organic complex with the drug. The optimum concentration for the hypoglycemic effect of 2CNP is determined to be 10 μM, which can be detected using an optical sensor. This compound also inhibits α-amylase and other enzymes involved in carbohydrate metabolism, leading to the accumulation of glycogen and lowering the blood glucose level.

5-Bromo-6-chloro-3-indolyl acetate is a chromogenic substrate that yields a magenta-colored product after cleavage. The chromophore 5-bromo-6-chloro-indoxyl is released, generating the observable color. It is used in bacterial esterase detection (e.g. Staphylococcus spp.).

4-Nitrophenyl beta-L-arabinopyranoside is a chromogenic substrate for beta-L-arabinosidase. Upon hydrolysis, para-nitrophenol is released yielding a yellowish colour. 4-Nitrophenyl beta-L-arabinopyranoside is used in different applications such as the Bacterial arabinan degradation assays, gut microbiome analysis

2-Naphthyl beta-D-galactopyranoside is a glycoside that is found in the flowers of the plant Eschscholzia californica. It is used as a localizer for bacterial strains and can be hydrolyzed by enzymes to release naphthalene. 2-Naphthyl beta-D-galactopyranoside has been shown to inhibit the growth of corynebacterium and diazonium salt, which may be due to its ability to bind to DNA and disrupt protein synthesis. The potential use of this molecule is for its insolubility, which prevents it from being absorbed by skin cells.

Calcium 2-naphthylphosphate, which is the calcim salt of 2-naphthylphosphate, is a chromogenic substrate to measure alkaline phosphatase activity. After enzymatic cleavage, the product yielded (2-naphthol) generates a red-colored complex upon reaction with a diazonium salt like Fast Blue RR or Fast Garnet GBC.

6-Chloro-3-indolyl b-D-glucuronide sodium salt is a chromogenic substrate for beta-glucuronidase, a reporter gene used to monitor gene expression by detecting the enzyme's activity. It yields a salmon colored precipitate upon cleavage.