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cyanocobalamin: see coenzyme; vitamin.
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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(or Vitamin B12), C63H88CoN14O14P, a cobalt-corrin complex in which the cobalt atom is bonded to a cyano group, a nucleotide residue, and four reduced pyrrole rings; molecular weight, 1355.40. Cyanocobalamin is a dark-red crystalline compound, which is soluble in water and polar organic solvents. It was first isolated in crystalline form from cattle liver. Its structure was established by A. Todd and D. Crowfoot Hodgkin and their co-workers.

The primary sources of cyanocobalamin in nature are microorganisms; cyanocobalamin is synthesized by several bacteria, by actinomycetes, and by blue-green algae. It occurs in almost all animal tissues. It is not encountered, as a rule, in the tissues of higher plants (legume tubers are an exception). In ruminants, it is synthesized in sufficient amounts by the microflora of the intestine and the rumen. In man and several higher animals, such as birds and hogs, its synthesis by intestinal microflora is insufficient, and thus the vitamin must be obtained from food. The daily requirement for humans is about 5 μg. The major sources of the vitamin are liver, kidneys, fish meal, and milk.

In the form of its coenzymes methylcobalamin and deoxyadenosylcobalamin, cyanocobalamin participates in the enzymic reactions involved in hematopoiesis and facilitates normal liver function and nerve fiber regeneration. It is produced by microbiological synthesis using propionic-acid bacteria for the fermentation process.

Vitamin B12 is used for the treatment of pernicious anemia and other anemias, as well as of diseases of the central and peripheral nervous systems and the liver. It is prescribed in solutions for intramuscular injections. (See alsoVITAMINS; ANEMIA; and COBALAMINS.)


Smith, L. Vitamin B12. Moscow, 1962. (Translated from English.)
Friedrich, W. Vitamin B12 und Verwandte Corrinoide, 3rd ed. Stuttgart, 1975.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


vitamin B12
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The research study provides estimates for Vitamin B12 (Cobalamin, Cyanocobalamin) Forecast till 2025*.
Update on oral cyanocobalamin (vitamin B12) treatment in elderly patients.
Our working group (CARE B12, Hopitaux Universitaires de Strasbourg) has developed an effective oral curative treatment for patients presenting with food-cobalamin malabsorption (FCM) and PA, using crystalline cyanocobalamin. (1) In a first study, we prospectively followed 10 patients with cobalamin deficiency and well-established FCM who received 3000 or 5000 mcg oral crystalline cyanocobalamin once a week for at least 3 months.
Conventional oral supplementation of cyanocobalamin is plagued by limited bioavailability.
Cyanocobalamin was administered (1.000 [micro]g/day intramuscularly) until the reticulocyte crisis occurred and serum vitamin B12 levels returned to the normal range.
Your cardiovascular health problems seem to have started before switching to the lower dose of cyanocobalamin.
Cobalt in the diet is converted by the micro-organisms in the rumen into vitamin B12 (cyanocobalamin) which is absorbed in the small intestine.
In total, 63 individuals were treated with a high oral dose of vitamin [B.sub.12] in the form of cyanocobalamin (5 mg/day) for 3 months ([B.sub.12]-treated vegan population).
The grown bacteria are allowed to metabolize a mixed gas, prepared by adding hydrogen to at least one of coal gas and biogas, into methane and at the same time, cobalamin contained in the fermented liquor is recovered as an extracellular product in the form of cyanocobalamin by using potassium cyanide to thereby produce vitamin B12 efficiently in a high content and high yield.
A synthetic form, called cyanocobalamin, is used to fortify foods and make dietary supplements in the United States.
A synthetic form, cyanocobalamin, is used in the United States to fortify foods and to make dietary supplements.
(Nasdaq NMS: NSTK), Bothell, Wash., has announced positive results from a bioequivalence study showing that its investigational nasal spray dosage form of cyanocobalamin (vitamin B12) is bioequivalent to Nascobal(R) (Cyanocobalamin, USP) nasal gel.