Listeria Enrichment Medium Base (UVM Medium)

 Principle

• Listeria Enrichment Medium Base (UVM Medium) is composed of tryptone, protease peptone, special peptone, yeast extract, sodium chloride, potassium dihydrogen phosphate, disodium hydrogen phosphate, and esculin.
• Tryptone, protease peptone, and special peptone serve as a source of carbon, nitrogen, amino acids, and other necessary elements for the growth. The phosphates provide buffering capacity.
• Sodium chloride maintains the osmotic equilibrium. Yeast extract provides vitamin B complex. Esculin is used for the identification of enterococci, enterococci hydrolyze esculin in the presence of bile salt. To increase the selectivity the medium can be fortified with antimicrobial agents.
• Trypaflavin (acriflavin) suppresses the growth of gram-positive microorganisms, Nalidixic acid, inhibits the growth of gram-negative organisms, whereas Cycloheximide inhibits the growth of saprophytic fungi.

 Use: Recommended for selective isolation of Listeria monocytogenes from clinical specimens.