Oxbile (Oxgall) is dehydrated bile for use in preparing microbiological culture media. Oxbile is manufactured from large quantities of fresh bile by rapid evaporation of the water content. Bile is composed of fatty acids, bile acids, inorganic salts, sulfates, bile pigments, cholesterol, mucin, lecithin, glycuronicacids, porphyrins, and urea. The use of Oxbile insures a regular supply of bile, and uniformity impossible to obtain with fresh materials. Oxbile is dehydrated fresh bile and prepared specifically for differentiation of bile tolerant microorganisms. A 10% solution of dehydrated bile is equivalent to a fresh bile solution. It is usually incorporated into media e.g., Bile Esculin Agar and Brilliant Green Bile Agar, used for the determination of enteric pathogens. Oxbile is also found in Littman Agar, a selective fungal medium. It is used as a selective agent for the isolation of Gram-negative microorganisms, inhibiting Gram-positive bacteria. The major composition of Oxbile is taurocholic and glycocholic acids.
