Oxidation Fermentation (OF) test is used to differentiate those organisms that utilize carbohydrates aerobically (Oxidation) such as Pseudomonas aeruginosa, from those that utilize carbohydrates anaerobically (Fermentation) such as members of the Enterobacteriaaceae and those that do not utilize carbohydrates at all (Non fermenters) such as Alcaligenes faecalis .