The Voges-Proskauer test detects which type of product from glucose fermentation?

The Voges-Proskauer test specifically detects the production of acetoin, a neutral end product formed during the fermentation of glucose by certain microorganisms. When glucose is fermented, some bacteria convert it through various pathways, producing different metabolic byproducts. In the case of the Voges-Proskauer test, the presence of acetoin is revealed through a series of chemical reactions with reagents, typically alpha-naphthol and potassium hydroxide, leading to a color change that indicates a positive result.

Acetoin acts as an intermediate in the butanediol fermentation pathway, which is typical of certain organisms like Enterobacter and some strains of Klebsiella. This differentiates it from ethanol, butyric acid, and acetic acid, which are other potential products of fermentation but are not detected by this specific test. Thus, the Voges-Proskauer test is a critical tool in microbiology for identifying bacteria based on their fermentation characteristics.