Löffler's medium

Löffler's medium is a special substance used to grow diphtheria bacilli to confirm the diagnosis.

In 1887, Friedrich Loeffler devised a culture medium containing horse serum, meat infusion, and dextrose for use in the cultivation of corynebacteria and for differentiating them from other organisms. Perry and Petran suggested modification of the original formulation. Buck, in 1949, described a modified Loeffler's medium for cultivating Corynebacterium diphtheriae.

This medium has a variety of uses in microbiological investigations. The current formulation incorporated these later modifications:

Heart muscle and animal tissue peptone provide the amino acids and other complex nitrogenous substances necessary to support growth of corynebacteria. Sodium chloride supplies essential ions.

Dextrose is a source of fermentable carbohydrate. The eggs and beef serum cause the medium to coagulate during the sterilization process and are sources of protein which are used for metabolism of the corynebacteria and other organisms.

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