Bile Esculin Azide Medium w/ Sterile Membrane Filter

Principle And Interpretation

DriFilter Membrane Nutrient Pad Medium are ready to use sterile culture media in the form of a 50 mm biological inert absorbent pads impregnated with standard culture medium, then dried and sterilized in 55 mm petri plate. They eliminate the need of laborious media preparation and autoclaving procedures. The nutrient pads are to be just rewetted with sterile distilled water and are ready to use. Use of nutrient pads allows larger sample volumes to be tested at a time. Interpretation of results is directly by counting the CFUs and also quantifies the microbial load present in the sample. Bile Esculin Agar was formulated by Swan (1) and evaluated by Facklam and Moody (2). Bile Esculin Azide Agar is modification of Bile Esculin Agar as per Isenberg (3). These media are selective and provide rapid growth of Group D Streptococci. These are highly nutritious media because of presence of casein enzymic hydrolysate, peptic digest of animal tissue and yeast extract. Sodium azide inhibits growth of gram-negative organisms and permits the cultivation of faecal Streptococci. Esculin hydrolysis and bile tolerance permit isolation and identification of group D Streptococci in 24 hours.