MANNITOL NITRATE MOTILITY MEDIUM 500 grams/bottle

Mannitol Nitrate Motility Medium is a semisolid medium that permits the rapid identification of Enterobacteria on the basis of motility, mannitol utilization and nitrate reduction to nitrite. Casein peptone provides the nitrogen, minerals, amino acids and nutrients essential for bacterial growth. Mannitol is a fermentable carbohydrate for energy source. Potassium nitrate provides additional nutrients and organisms capable of reducing nitrate show increased motility. Phenol red is a pH indicator. Bacteriological agar is the solidifying agent. Motile bacteria show a diffuse turbidity away from the inoculation line, while non-motile organisms only grow along the stab line. If mannitol is fermented, the medium changes its color from red to yellow. Nitrate reduction tests are conducted adding Gries Reagent (2 drops of solution A, and then 2 drops of the solution B) to the surface of the medium. Nitrate-negative organisms are unable to reduce nitrates and they yield no color after adding the reagent. Nitrate-positive: The appearance of a pink or red coloration indicates that the nitrates have been reduced to nitrites.