Hayward, CA – Biolog, Inc. today announced that the proprietary chromogenic medium, Rainbow Agar O157, has been added to the United States Department of Agriculture (USDA) Food Safety Inspection Service (FSIS) guidelines.  Rainbow Agar was designed to allow microbiologists to isolate and detect pathogenic organisms in one step.

The patented Rainbow Agar O157 formulation is superior to other media because it provides a high degree of selection and enrichment as well as the most specific colorimetric test for O157, with colonies forming a very distinctive gray/black color. A recent scientific evaluation of several chromogenic media found Rainbow Agar O157 to be clearly superior in providing the lowest level of false positives (M. Manafi et al, Food Micro 99, posted on www.univie.ac.at/chromogenic/)

Reportedly up to 25% of EHEC (enterohemorrhagic E. coli) outbreaks around the world are caused by non-O157:H7 toxigenic strains of E. coli.  Rainbow Agar O157 also provides the microbiologist the ability to isolate other toxigenic strains which usually grow as dark blue or purple colonies (T.J. Novicki et al, J. Clin. Micro. [2000] 38:547).

Rainbow Agar O157 has already been approved by the Japanese Ministry of Health for use in detection of E. coli O157.  Considering all the media products available to detect E. coli O157, selection of Rainbow Agar O157 in the FSIS guidelines is a significant recognition of performance.   A copy of the FSIS guidelines can be downloaded from the Biolog website.  For more information, contact Biolog at (510) 785-2564 or visit the Biolog website at http://www.biolog.com/.