Motility Indole Urease Agar 500gm Himedia India

Motility Indole Urease Agar is also called MIU Medium. MIU Medium Base is recommended for the detection of motility, urease, and indole production in a single tube. Motility and urease reactions are read before testing Indole production. Motile organisms show either diffused growth or turbidity extending away from the stab inoculation line while nonmotile organisms grow along the stabline. Organisms that utilize urea, produce ammonia which makes the medium alkaline, showing a pink-red color by change in the phenol red indicator. Indole is produced from tryptophan present in tryptone. The indole produced combines with the aldehyde present in the Kovac’s reagent to form a red complex.

Composition of Motility Indole Urease Agar

• Tryptone 10.000 Gms / Litre
• Dextrose (Glucose) 1.000
• Sodium chloride 5.000
• Phenol red 0.010
• Agar 2.000
• Final pH ( at 25°C) 6.8±0.2
• Formula adjusted, standardized to suit performance parameters

Directions of Motility Indole Urease Agar

Suspend 18 grams in 950 ml purified/distilled water. Heat to boiling to dissolve the medium completely. Dispense in 95 ml amounts into flasks and sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes. Cool to about 50-55°C and add aseptically 5 ml sterile 40% Urea solution (FD048) per 95 ml basal medium. Mix well and dispense into sterile test tubes. Allow to cool in an upright position.

Principle And Interpretation

MIU Medium Base is formulated to detect motility, urease, and indole production in a single tube. Tryptone provides amino acids and other nitrogenous substances. Sodium chloride maintains osmotic equilibrium. Dextrose is a fermentable carbohydrate. Phenol red is the pH indicator which turns pink-red in alkaline conditions.
The test cultures are stab-inoculated.
Motility and urease reactions are read before testing Indole production. Motile organisms show either diffused growth or turbidity extending away from the stab inoculation line while nonmotile organisms grow along the stabline. Organisms that utilize urea, produce ammonia which makes the medium alkaline, showing a pink-red color by a change in the phenol red indicator (5). Indole is produced from tryptophan present in tryptone (1,4). The indole produced combines with the aldehyde present in the Kovac’s reagent to form a red complex.

Click to Know More