Technical Data

E3325
Grade
Microbiological Grade
EU Commodity Code
38210000
Shipping Temp
RT
Storage Temp
RT/4°C
Eosin Methylene Blue Agar (Powder)
HH&T

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.
Microbiological Analysis
Enterococcus faecalis ATCC 29212: Partial Inhibition, colorless
Escherichia coli ATCC 11775: Growth, blue-black colonies with dark center and green metallic sheen.
Salmonella typhimurium ATCC 14028: Growth, colorless colonies
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.
Appearance
Light reddish-purple, homogeneous, free flowing powder.
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, colorless Escherichia coli ATCC 25922: Growth, blue-black colonies with dark center and metallic sheen. Salmonella typhimurium ATCC 14028: Growth, colorless colonies
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.
Directions per Liter Dissolve 36 grams in 800-900ml of ddH2O stirring gently with heating until completely solubilized. Add additional water to bring the solution to1L. Dispense into appropriate containers, loosen caps and autoclave for 15 minutes at 121ºC (15psi).
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 refrigerated and used within a short period of time.
Media Formulation
Components shown as g/liter
Pancreatic Digest of Gelatin10.0
Lactose5.0
Dipotassium Phosphate2.0
Sucrose5.0
Eosin Y0.4
Methylene Blue0.065 
Agar13.5
Total:36g/liter

Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.

References
No references available
USBio References
No references available
United States Biological | 4 Technology Way | Salem, MA 01970
Phone 800-520-3011 | Fax 978-594-8052 | Website www.usbio.net