Selective medium used to detect gram negative enteric bacteria. Contains both lactose and sucrose.
Description:Eosin Methylene Blue Agar was first developed by Holt-Harris and Teague. This formula contains both lactose and sucrose with the two indicator dyes, eosin Y and methylene blue. Escherichia and Enterobacter species can be easily distinguished from other Gram negative enteric bacilli using this medium. EMB Agar contains two mildly selective dyes, eosin Y and methylene blue, which interact under strong acidic conditions to impart metallic sheen to Escherichia coli colonies. In addition, E coli produces dark blue-black colonies. Other coliforms produce mucoid, pinkish brown colonies. Non-lactose fermenting bacteria Salmonella and Shigella, produce translucent or colorless colonies. Acinetobacter, Aeromonas, Pseudomonas, Plesiomonas and Yersinia also grow on this medium. Gram-positive bacteria are inhibited by eosin Y. The slow lactose fermenters also ferment sucrose which reduces the incidence of false-positive interpretations.
Storage and Stability:Store powdered media at RT. Opened bottles should be capped tightly and kept in a dark, low humidity environment. Prepared media should be kept at 4°C and used within a short period of time.
Solubility:Dark bluish to reddish-purple, clear to slightly turbid.
pH (25°C):7.2±0.2
Microbiological Analysis:Enterococcus faecalis ATCC 29212: Partial Inhibition, colorlessEscherichia coli ATCC 25922: Growth, blue-black colonies with dark center and metallic sheen
Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.
