Hektoen Enteric Agar

Hektoen Enteric Agar is used for the isolation and differentiation of enteric pathogens in a laboratory setting. Hektoen Enteric Agar is not intended for use in the diagnosis of disease or other conditions in humans.

Hektoen Enteric Agar was developed in 1967 by King and Metzger. Compared to other enteric differentiating media commonly used, Hektoen Enteric Agar increased the isolation rate of Salmonella spp. and Shigella spp. This was accomplished by increasing the carbohydrate and peptone content of the medium in order to counteract the inhibitory effects of bile salts and indicators. King and Metzger formulated a medium that slightly inhibited growth of Salmonella and Shigella, while inhibiting Gram-positive microorganisms.


Formula Liter
Enzymatic Digest of Animal Tissue 16.5 g
Yeast Extract 3 g
Bile Salts Mixture 4.5 g
Lactose 12 g
Sucrose 12 g
Salicin 2 g
Sodium Chloride 5 g
Sodium Thiosulfate 5 g
Ferric Ammonium Citrate 1.5 g
Bromthymol Blue 0.065 g
Acid Fuchsin 0.1 g
Agar 13.5 g

Final pH: 7.6 ± 0.2 at 25°C
Formula may be adjusted and/or supplemented as required to meet performance specifications.


  1. Suspend 75 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.

Order Details

Product # Product Description
7138A Hektoen Enteric Agar, 500 g
7138T Hektoen Enteric Agar, 5 kg