Eosin Methylene Blue Agar

Eosin Methylene Blue Agar (Holt, Harris & Teague) is used for the isolation and differentiation of Gram-negative enteric bacilli in a laboratory setting. Eosin Methylene Blue Agar is not intended for use in the diagnosis of disease or other conditions in humans.

Eosin Methylene Blue Agar (EMB) was developed by Holt-Harris and Teague. This formula contains lactose and sucrose with two indicator dyes, Eosin Y and Methylene Blue. The use of Eosin Y and Methylene Blue as indicators produced sharp and distinct differentiation between colonies of lactose fermenting and non-fermenting organisms. Sucrose is included to detect coliforms that ferment sucrose more readily than lactose. EMB Agar is selective due to the presence of an inhibitor and differential based on the ability of some organisms to ferment carbohydrates with the absorption of an Eosin Y and Methylene Blue complex.

EMB Agar is recommended for use in examining clinical specimens for enteric pathogens.


Formula Liter
Enzymatic Digest of Gelatin 10 g
Lactose 5 g
Sucrose 5 g
Dipotassium Phosphate 2 g
Eosin Y 0.4 g
Methylene Blue 0.065 g
Agar 13.5 g

Final pH: 7.2 ± 0.2 at 25°C
Formula may be adjusted and/or supplemented as required to meet performance specifications.


  1. Suspend 36 g of the medium in one liter of purified water.
  2. Heat with frequent agitation and boil for one minute to completely dissolve the medium.
  3. Autoclave at 121°C for 15 minutes.

Order Details

Product # Product Description
7134A Eosin Methylene Blue Agar (Holt, Harris & Teague), 500 g