Card Set Information
What is the objective of Oxidation Fermentation test?
Differentiate bacteria based on their ability to oxidative and/or fermentative metabolism of carbohydrates
What is the product of Oxidative metabolism of carbohydate?
CO2,H2O, and energy
What is the difference between Oxidation and Fermentation?
Fermentation doesn't use O2 as final electron acceptor. Pyruvate and other organic intermediates reduced to organic acids, gas, or alcohol
Why is there a high sugar to peptone ration in Hugh and Leifson's O-F medium?
To prevent alkaline product from peptone to neutralize weaker acids made from oxxidation of the carbohydrate
What is the indicator used in O-F test?
How does bromthymol blue indicate changes in pH?
It turn yellow at pH 6, green at pH 7.1 and blue at pH 7.6
What does the semi solid medium help in the test?
Allow us to see motility
What does the mineral oil promote?
Mineral oil promote an anaerobic growth and fermentation. (Inhibit oxidation). Air can't diffuse through the oil to the medium
How would you determine that a bacteria can oxidize and ferment?
If the bacteria turn the O-F tube yellow in aerobic and anaerobic condition
How would you know if the bacteria is only oxidize or only ferment?
If the bacteria only turn the O-F tube yellow in either aerobic or anaerobic condition
What does it mean when the aerobic and anaerobic O-F tube both turn green?
Bacteria can't oxidize or ferment the sugar
What does it mean if the top of the O-F test tube turn blue?
Alkaline product from amino acid degradation
Which bacteria does O-F test differentiate?
Fermentative Enterobacteriaceae from the oxidative Pseudomonas and Bordetella, and the non reactive Alcaligenes and Moraxella
What is catabolism?
breakdown of molecules (releases energy)
What is anabolism?
formation of molecules (require energy, store energy)
What is nonsaccharolytic bacteria?
Bacteria that can degrade amino acid(turn the O-F tube basis and blue)