Endo Agar w/ NaCl 500G

Endo Agar w/ NaCl is used for detection and isolation of pathogenic enteric bacilli. Gram-negative bacteria can be differentiated on the basis of lactose fermentation, while inhibiting gram-positive bacteria. Sodium sulphite and basic fuchsin inhibits most of the gram-positive bacteria. Lactose fermenting Escherichia coli and coliforms produce aldehyde and acid. The aldehyde liberates fuchsin from the fuchsin-sulphite complex and colonies of lactose fermenters appear dark red. Non-lactose fermenters such as Salmonella show colourless colonies. Escherichia coli exhibits a permanent greenish metallic luster (fuchsin luster) to the colonies due to crystallization of fuchsin.