A laboratory procedure determines the ability of microorganisms to ferment glucose, producing acid and/or gas as byproducts. A typical setup involves inoculating a glucose broth with the target organism and observing for changes in a pH indicator, often accompanied by a Durham tube to capture gas production. A positive test typically manifests as a color change in the broth (e.g., from red to yellow) indicating acid production, and potentially a visible gas bubble trapped within the Durham tube. For example, Escherichia coli typically produces both acid and gas when fermenting glucose, while some other bacteria might produce only acid.
This analysis offers a crucial tool for identifying and differentiating bacterial species, informing diagnoses and treatment strategies. Historically, carbohydrate fermentation tests, including glucose fermentation, have been foundational in the field of microbiology, playing a significant role in differentiating diverse microbial groups. These metabolic characteristics provide insights into the biochemical capabilities of an organism, aiding in taxonomic classification and epidemiological studies. This test’s simplicity, cost-effectiveness, and speed make it valuable in diverse settings, from educational laboratories to clinical diagnostics.