Abstract
In 1941 Kuhn and Jerchel, while working on "invert soaps", first recorded use of tetrazolium salts in research. These investigators, after discovering that triazolium salts possessed notable disinfectant action, studied the tetrazolium salts for similar properties. They reported distinct antibacterial action using varied concentrations of the compound. | As early as 1875, Friese prepared formazan, and in 1894 von Pechmann and Runge isolated the pure salt (2,3,5-triphenyl-tetrazolium chloride). Since then the salt has undergone intensive chemical study and utilization, but only in the last twenty years has it found new application in biological and medical research. | The reduction of a tetrazolium salt and subsequent formation of the red colored formazan can be accomplished by the natural metabolic mechanisms of various biological systems. Several species of bacteria bring about this reduction, among which are the various strains of enterococci. | The enterococci were particularly selected for this problem because they possess a number of characteristics that are favorable for laboratory work.