The Islamic University of Gaza Faculty of Science Voges Proskauer Test Name : Sohad M. Mattar Dr.: Abd ERauof El Manaama

Introduction Principle. Principle. Significance Significance Procedures. Procedures. Results. Results. Summary. Summary.

Principle Voges-Proskauer tests demonstrate an organisms ability to convert pyruvate to acetoin (in the course of glucose fermentation). Voges-Proskauer tests demonstrate an organisms ability to convert pyruvate to acetoin (in the course of glucose fermentation).

Significance Valuable tool in distinguishing Klebsiella, Enterobacter, Ewingella and Serratia from other members of Enterobacteraceae. Valuable tool in distinguishing Klebsiella, Enterobacter, Ewingella and Serratia from other members of Enterobacteraceae. As well as distinguishing between Proteus vulgaris (V-P negative) and P. mirabilis (V- P positive). As well as distinguishing between Proteus vulgaris (V-P negative) and P. mirabilis (V- P positive).

Procedures Inoculate buffered glucose broth with the organism and incubate at 37°C for 3 days. Inoculate buffered glucose broth with the organism and incubate at 37°C for 3 days.buffered glucose brothbuffered glucose broth Add approximately 3 ml of alpha napthol, followed by 1 ml of 40% KOH. Add approximately 3 ml of alpha napthol, followed by 1 ml of 40% KOH. Mix well and allow to stand for 30 minutes. Mix well and allow to stand for 30 minutes.

Results Voges-Proskauer Test Left: uninoculated control Right: negative (copper color) Left: uninoculated control Right: positive (red color )

Special Feature The test is used to differentiate between genera. eg. K. pneumonia (+) and Enterobacter (+) from E. coli (-) The test is used to differentiate between genera. eg. K. pneumonia (+) and Enterobacter (+) from E. coli (-)

Klebsiella pneumonia

E-coli

Summary Voges-Proskauer tests to detect the production of acetylmethylcarbinol (actoin), a natural product formed from pyruvic acid in the course of glucose fermentation. Voges-Proskauer tests to detect the production of acetylmethylcarbinol (actoin), a natural product formed from pyruvic acid in the course of glucose fermentation. The test is prepared as mentioned before. The test is prepared as mentioned before. Red color is a positive result however the copper color is negative. Red color is a positive result however the copper color is negative. Distinguishing some kinds of Enterobacteraceae from other members. Distinguishing some kinds of Enterobacteraceae from other members.