for detection of starch hydrolysing microorganisms.
STARCH AGAR is used for detection of starch hydrolysing microorganism. This medium was formulated by Vedder in 1915. Although the medium was originally formulated to perform the test for the identification of Bacillus cereus, it can be applied to any kind of microorganism where starch hydrolysis activity is required to be analyzed. Yeast extract, Beef extract and peptic digest of animal tissue provide nitrogenous compounds, sulphur,carbon trace elements e.t.c. Sodium chloride maintains the osmotic balance.Flood the surface of 48 hours old culture on Starch Agar with Grams Iodine (TBL 034). Starch hydrolysis is seen as a colourless zonesurrounding the colonies. A blue or purple zone indicates that starch is not hydrolyzed. Size of the clear zone is directly proportional to the starch hydrolyzing activity of the strain under study.