Lichenin

Lichenin
Other names Lichenan; Moss starch
Identifiers
CAS number	1402-10-4
Properties
Molecular formula	(C6H10O5)x
Molar mass	Variable
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Lichenin, also known as lichenan or moss starch, is a complex glucan occurring in certain species of lichens. It can be extracted from Cetraria islandica (Iceland moss).^[1] It has been studied since about 1957.^[2] Chemically, lichenin consists of repeating glucose units linked by β-1,3 and β-1,4 glycosidic bonds.^[3]

It is an important carbohydrate for reindeers and northern flying squirrels, which eat the lichen wila.

It can be extracted by digesting Iceland moss in a cold, weak solution of carbonate of soda for some time, and then boiling. By this process the lichenin is dissolved and on cooling separates as a colorless jelly. Iodine imparts no color to it.^[4]

Other uses of the name

In his 1960 novel Trouble with Lichen, John Wyndham gives the name Lichenin to a biochemical extract of lichen used to extend life expectancy beyond 300 years.

References

1. ^ Perlin, A.S.; Perlin AS, Suzuki S (1962). "The Structure Of Lichenin: Selective Enzymolysis Studies". Canadian Journal of Chemistry (Canada: National Research Council of Canada) 40 (1): 50–56. doi:10.1139/v62-009. 
2. ^ Cunningham, WL; Cunningham WL, Manners DJ (March 1964). "Studies on carbohydrate-metabolizing enzymes. 11. The hydrolysis of lichenin by enzyme preparations from malted barley and Rhizopus arrhizus". The Biochemical journal (England: Published by Portland Press on behalf of the Biochemical Society) 90 (3): 596–602. ISSN 0264-6021. PMC 1202740. PMID 5833367. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1202740. 
3. ^ A.S. Perlin and S. Suzuki (1962). "The Structure of Lichenin: Selective Enzymolysis Studies". Canadian Journal of Chemistry 40: 50–56. doi:10.1139/v62-009. 
4. ^  This article incorporates text from a publication now in the public domain: "Lichenin". New International Encyclopedia. 1905.