cyanocobalamin

Chemical name for vitamin B₁₂, which is normally produced by micro-organisms in the gut. The richest sources are liver, fish, and eggs. It is essential to the replacement of cells, the maintenance of the myelin sheath which insulates nerve fibres, and the efficient use of folic acid, another vitamin in the B complex. Deficiency can result in pernicious anaemia (defective production of red blood cells), and possible degeneration of the nervous system.

It has a complex chemical structure containing several rings arranged around a central cobalt ion. Production of cyanocobalamin is by a controlled fermentation.