Tetrazolium Violet

Tetrazolium violet (TZV) is a tetrazolium salt (TTZ), is widely used for microbiological studies as a redox indicator to indicate cellular respiration. Tetrazolium salts are colourless compounds which become coloured when reduced to formazans. Traditionally used as indicators of cell metabolism in eukaryotes and prokaryotes, they function as artificial electron acceptors and thus detect dehydrogenase activities. The production of coloured formazan is irreversible and can be quantified using spectrophotometry. TZV forms a water-insoluble formazan. This salt is positively charged and considered as cell permeable. The positive charge is thought to facilitate cellular uptake due to the membrane potential. It is generally used as indicators of cell redox activity in order to test resistance to solvents, drug susceptibility or specific substrate utilization. It also enables the discrimination of viable cells in populations of respiring bacteria and anaerobic bacteria). It can help to enumerate microbial colonies in solid culture media, and to detect microbial contamination in food. Tetrazolium violet (TZV) is an important pharmaceutical intermediate for the preparation of biological active substances. High concentrations of TZV can lead to total inhibition of bacterial growth and has been shown to have antitumor properties, by inducing apoptosis and blocking cell cycle progression in G1 phase.