Kovac's reagent

Kovacs reagent is a biochemical reagent consisting of isoamyl alcohol, para-dimethylaminobenzaldehyde (DMAB), and concentrated hydrochloric acid. It is used for the diagnostical indole test, to determine the ability of the organism to split indole from the amino acid tryptophan. The indole produced yields a red complex with para-dimethylaminobenzaldehyde under the given conditions. This was invented by the Hungarian-Swiss Chemist, Ervin Kovats (Erwin Kovacs) (1927–2010).

Ehrlich's reagent is similar but uses ethyl alcohol or 1-propyl alcohol.

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