Brain Heart Infusion Agar is used for the cultivation of fastidious microorganisms. Brain Heart Infusion, Peptic Digest of Animal Tissue, and Pancreatic Digest of Casein provide a source of carbon, nitrogen, and vitamins. Dextrose is the fermentable carbohydrate. Sodium Chloride supplies essential electrolytes and maintains the osmotic equilibrium. Disodium Phosphate acts as pH buffer. Agar is the gelifying agent.