Lichenin

LICHENIN (lichen starch), a carbohydrate that serves as material for building cell walls in certain lichens, particularly in Iceland moss (Cetraria islandica). It is extracted from plant material with hot water and then separated from the solution by freezing. In dry form, it is a brittle, translucent mass that swells in cold water and dissolves in hot water. Upon cooling, it separates out as a jelly. It is optically inactive, does not stain with iodine, and breaks down into glucose during acidic hydrolysis. In medicine, it is used as a coating substance. In some invertebrates, an enzyme called lichenase has been found, capable of breaking down L.