DEVELOPMENT OF MEDIUM FOR DIFFERENTIATION BETWEEN YERSINIA ENTEROcOLITICA AND OTHER BACTERIA

A new dye containing medium, (Yersinia-2, 3, 5-tripheny
tetrazolium chloride-roso bengal Agar, YTRA) was developed for
differentiation between Yersinia enterocolitica and other bacteria
ThoYTRAmedium was compared with cefs ulo din irgas an
novobiocin (cIN) medium, which is tho most popular mo dium to
differentiate and enumerat Yorsinia enterocolitica. Soveral
combinations of twenty threo dyes woro ovaluated to develop the
new medium. 2, 3, 5 Triphenyl tetrazolium chloride (0.05 g/liter) and
rose bengal (0. 05 g/iter) on Brafn Hoart InfuSion Agar were found
 
as thobest combin ation for differentiation between Yersinia
enterocolitica and other bacteria. On the slightly red YTRA medium,
Yersinia enterocolitica produced metallic sheen colonies, whereas
other growing bacteria produced red color colonies. The recovery
rates of Yersinia enterocolitica from inoculated ground beef, and
milk were significantly ditferent between Cefsulodin-irgasan-
novobiocin (CIN) and Yersinia- 2, 3, 5-triphenyl tetrazolium
chloride-rose bengal Agar (YTRA) media. The recovery rates of heat
injured Yersinia enterocolitis ere also highly Countable on YTRA
medium.