Practical Procedure

Voges Proskauer (VP) Test – Principle, Procedure, Results

In 1898, Voges as well as Proskauer (16)characterized the process of fermentation of sugars by a variety of bacteria. They demonstrated that the gas that was produced during the process was a mixture of H2 and CO2 that when they added KOH to the cultures been grown in glucose peptone medium to allow for a prolonged period of incubation in presence of oxygen certain organisms developed a red fluorescent color. While the exact nature of the color was not known in the early days, this technique was suggested to differentiate between the bacterial strains that produced it and ones that didn't. in 1906 Arthur Harden analyzed the fermentation products of Enterobacter aerogenes. He discovered that when it was surrounded by glucose, the organism made two compounds, acetoin as well as 2,3-butanedio.