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|Section2= |Section6= |Section7= }} Cyanocobalamin is the most common and widely produced form of the chemical compounds that have vitamin B12 activity. Vitamin B12 is the "generic descriptor" name for any of such vitamers of vitamin B12. Because the body can convert cyanocobalamin to any one of the active vitamin B12 compounds, by definition this makes cyanocobalamin itself a form (or vitamer) of B12, albeit a largely artificial one. Cyanocobalamin usually does not occur in living organisms, but animals can convert commercially produced cyanocobalamin into active (cofactor) forms of the vitamin, such as methylcobalamin.〔 ==Chemical properties== Cyanocobalamin is the most famous and widely manufactured vitamer in the vitamin B12 family (the family of chemicals that function as B12 when put into the body), because cyanocobalamin is the most air-stable of the B12 forms. It is the easiest to crystallize and, therefore, easiest to purify after it is produced by bacterial fermentation, or synthesized ''in vitro''. It can be obtained as dark red crystals or as an amorphous red powder. Cyanocobalamin is very hygroscopic in the anhydrous form, and sparingly soluble in water (1:80). It is stable to autoclaving for short periods at . The vitamin B12 coenzymes are very unstable in light. In animals the cyanide ligand is replaced by other groups (adenosyl, methyl), which are the biologically active forms. The remaining portion of the cyanocobalamin remains unchanged. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cyanocobalamin」の詳細全文を読む スポンサード リンク
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