CDC Anaerobic Agar is used for the isolation and cultivation of obligate anaerobes. Casein Digest of Peptone and Papaic Digest of Soybeans supply amino acids, peptides, and carbohydrates. Yeast Extract is a source of B-complex vitamins and trace elements. L-Cystine is a reducing agent. Sodium Chloride maintains osmotic equilibrium and Agar is the gelifying agent.