Endo-Agar

Endo Agar ( lactose -Fuchsin sulfite agar ) developed by the Japanese bacteriologist Shigeru Endō ( 1869-1937 ), is a selective medium, which is in microbiology for the cultivation of enterobacteria, in particular coliform bacteria use. These utilize the lactose contained while producing aldehydes and organic acids. The aldehydes set free from the fuchsin fuchsin - sulfite complex and stain the colonies deep purple to reddish. Colonies of Escherichia coli also show a characteristic yellowish- green glow when the fuchsin crystallizes ( Fuchsinglanz ). Gram-positive bacteria was inhibited by sodium sulfite and fuchsin largely on growth. Characteristic is the slightly violet to pink color of the culture medium. By oxidation of sulfite it is more reddish colored and unusable. To avoid loss of quality it should always be stored in the dark.