ERLICH

Alternative reagent for Kovacs indoles, as is considered more sensitive. Requires organic extraction with ether or xylene prior to administration. Today used alone or in combination with other biochemical tests for the characterization of coliforms (Gram negative, non-sporulating bacillus). Still considered a classic test for differentiation of indole-positive E. coli from indole-negative. Enterobacter, Kleibsiella.