MIU Medium Base is recommended for detection of motility, urease and indole production in single tube. Motility and urease reactions are read before testing Indole production. Motile organisms show either diffused growth or turbidity extending away from stab inoculation line while nonmotile organisms grow along the stabline. Organisms that utilize urea, produce ammonia which makes the medium alkaline, showing pink-red colour 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.