LISTERIA ENRICHMENT MEDIUM BASE (UVM I)

Description

Listeriosis is caused by Listeria monocytogenes, a short gram-positive non-sporulating rod. The bacilli are commonly found in soil and in the intestines of many animals including birds, fish, barnyard animals, dairy cattle and household pets. It is transmitted to humans by foods contaminated with faecal matter, as well as by the consumption of animal foods contaminated with the bacilli. Listeria Enrichment Medium Base is used for the selective cultivation and isolation of L. monocytogenes from clinical samples. The medium was originally formulated by Donnelly and Baigent. It was later modified by decreasing the nalidixic acid concentration in the selective supplements and subsequently increasing the acriflavin concentration. University of Vermont Modification Medium (UVM) used a two-step selective enrichment medium resulting in a higher isolation rate of L.monocytogenes from meat products within 3-4 days. This UVM Broth is recommended as a primary enrichment broth for recovery of heat-injured Listeria.