MACCONKEY AGAR, MODIFIED
MacConkey Agar, Modified is a solid medium recommended for the isolation of Klebsiella spp. from water samples. The medium contains Crystal Violet and Bile Salts that inhibit Gram-positive organisms and allow Gram-negative organisms to grow. Peptone and Proteose Peptone provide nitrogenous compounds, carbohydrates, vitamins, and minerals, while Inositol is the fermentable carbohydrate. Sodium Chloride maintains the osmotic balance and Neutral Red serves as pH indicator. Agar is the gelifying agent. Addition of Carbenicillin makes the medium selective for Klebsiella.