Violacein is an intense violet pigment formed by the condensation of two tryptophan units, found in a number of bacteria, notably Chromobacterium violaceum. The regulation of pigment biosynthesis is the chromogenic basis for the use of C. violaceum CV26 for the detection of quorum sensing mediators. Violacein cell toxicity resembles TNF-α signal transduction.
Violacein is soluble in ethanol, methanol, DMF and DMSO.