MOTILITY-INDOLE-LYSINE MEDIUM (MIL MEDIUM) (VEG.)

This medium is prepared by completely replacing animal based peptone with vegetable peptones making the medium free of BSE/TSE risks. MIL Veg Medium is the modification of MIL Medium which is formulated according to Reller and Merrett. It provides 4 differential reactions in a single culture tube. It is recommended to use along with Triple Sugar Iron (TSI) Veg Agar and Urea Veg Agar Base so as to enable initial identification of members of Enterobacteriaceae. Cultures are stab-inoculated and incubated at 37?C for 18-24 hours. Motility, lysine deamination and lysine decarboxylation reactions are read before testing indole reaction. Motility is indicated by diffused growth. Non- motile cultures grow along with stab line. Lysine deamination is observed as red or red-brown colour at the top of the medium while decarboxylation shows a purple colour throughout the medium. This colour may vary in intensity, may be a light colour due to reduction of indicator. For testing indole production add 3-4 drops of Kovac?s reagent to the medium. A pink to red coloured ring indicates a positive reaction.

for identi?cation of members of Enterobacteriaceae on the basis of motility, lysine decarboxylase, lysine deaminase and indole production