ESCULIN MANNITO AGAR

Description

Staphylococci are widespread in nature, although they are mainly found on the skin, skin glands and mucous membranes of mammals and birds. The coagulase-positive species i.e Staphylococcus aureus is well documented as a human opportunistic pathogen and also considered potent pathogen from the point of view of food hygiene The ability to clot plasma continues to be the most widely used and accepted criterion for the identification of pathogenic staphylococci associated with acute infections. Group D Streptococci possess the group D lipoteichoic acid antigen in their cell walls. Former Group D species, which are predominant normal inhabitants of the human gastrointestinal tract, are termed as faecal Streptococci or Enterococci. The unique ability of Enterococci to split esculin was reported by Meyer and Schonfeld. The use of esculin hydrolysis in identification of Enterococci was first cited by Rochaix. Enterococcus species hydrolyse esculin and hence black precipitate is observed around the colonies. This medium helps in smultaneous differentiation of Enterococcus and Staphylococcus based on mannitol fermentation and esculin hydrolysis.