Chromogenic-fluorogenic substrate test

Four methods may be used to detect and enumerate total coliforms, fecal coliforms, and E. coli in water samples. These are grouped as (a) multiple tube fermentation technique also known as the MPN technique, (b) membrane filtration technique, (c) presence/absence test, and (d) use of the enzymatic substrates test also known as the chromogenic-fluorogenic substrate test. 

This review will emphasize those areas where this new test procedure has reached its potential and those where more work is needed so that these substrates can be accepted in routine laboratory hemostasis testing. The list of literature presented is up to late 1984. The reader is referred to several excellent reviews on chromogenic and fluorogenic peptide substrates that have been previously published (F3, F5, F6, H5, S9, S16, TIO). 

Most of the early tests were based on the hydrolysis of the natural sphingolipid which had been labelled in the hydrophilic portion. Thus, the substrate and products could be easily separated by two-phase solvent partition or by precipitation of the product. In many cases artificial chromogenic or fluorogenic glycosides could be used instead of radiolabelled substrates. However, in these cases it is very important to demonstrate that the conditions and specificities of the enzynie reactions are such that the results can be extrapolated to the natural substrate (e.g. Peters et al., 1975). Thus, in the case of Niemann-Pick or Krabbe s diseases the unsubstituted... 

Manafi, M. (1996). Fluorogenic and chromogenic substrates in culture media and identification tests. Int.. Food Microbiol. 31 45-58. 

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