Moeller Decarboxylase Broth w/ Arginine HCl

Moeller Decarboxylase Broth w/ Arginine HCl is used for differentiation of bacteria on the basis of their ability to decarboxylate L-Arginine hydrochloride. Arginine is first hydrolyzed to ornithine which is then decarboxylated to form putrescine. Formation of the amine putrescine increases the pH of the medium, changing the colour of the indicator from yellow to purple. Bromo cresol purple is the pH indicator.If the organisms do not produce the appropriate enzyme, the medium remains acidic, yellow in colour.Pseudomonas aeruginosa shows poistive Arginine decarboxylase activity, Salmonella and Shigella species shows delayed positive activity.