GLYCEROL MANNITOL ACETAMIDE CETRIMIDE AGAR (DOUBLE PACK)

Description

Gilardi and others showed that a wide variety of non-fermenting organisms were capable of utilizing acetamide by using basal mineral media. However very few organisms growing in the medium metabolize acetamide by the process of deamination (acrylamidase activity). This unique ability is useful in identification of various non-fermenting gram-negative organisms. This ability is shown by Pseudomonas aeruginosa. Acetamide deamination leads to the liberation of ammonia, which thereby increases the pH of the medium, leading to a subsequent colour change of the phenol red indicator from yellow orange to cherry red. The medium was distributed in tubes as slants. The tubes were streaked and then incubated in water bath at 41-43?C for 24-48 hours. Ps. aeruginosa grew luxuriantly with a colour change from yellow orange to cherry red. The medium can also be used to enumerate Ps. aeruginosa in contaminated materials. The contaminated lake water or sewage were spread directlyon GMAC Agar in Kolle flasks and incubated at 41-43?C for 20-48 hours. After incubation the colonies surrounded by red zones were counted as Ps. aeruginosa. This medium does not support the growth of most organisms.