BILE SALT AGAR

Bile Salt Agar is used for isolation and enumeration of enteric bacilli. Enteric bacilli include a variety of gram-negative bacilli, frequent inhabitant of the intestine as normal commensals or pathogens. They are mostly members of the Enterobacteriaceae family but members of other taxonomical groups (e.g. Vibrionaceae) are also considered in this category. These organisms can cause either intestinal or extra-intestinal infections. The medium contains peptone and meat extract which provide nitrogenous compounds and other essential nutrients for the growth of enteric bacilli. Sodium taurocholate inhibits contaminating gram-positive organisms. Sodium chloride maintains the osmotic balance of the medium. Bile Salt Agar is additionally used for isolation and identification of organisms like Vibrio species, that can grow in the presence of bile salts. Bile Salt Agar promotes easy identification of colony characteristics to differentiate organisms suspected during initial screening. For confirmation, other tests such as slide agglutination can be done. The medium is useful in the analysis of food samples in which selective recovery of enteric organisms is required. Accurate results can be obtained with appropriate processing of the sample, incubation and identification of colonies in routine microbiological examination.

for isolation and enumeration of bile tolerant enteric bacilli