Vitamin B 12, also known as cobalt amine, is the only vitamin containing metal elements. In nature, vitamin B12 is synthesized by microorganisms. Higher animals and plants cannot make vitamin B12. Vitamin B12 is the only vitamin that requires the help of an intestinal secretion (endogenous factor) to be absorbed. Some people due to gastrointestinal abnormalities, lack of this endogenous factor, even if adequate dietary sources can also suffer from malignant anemia. There is basically no vitamin B12 in vegetable foods. It stays in the gut for a long time and takes about three hours (most water-soluble vitamins take only a few seconds) to be absorbed. Vitamin B 12's main physiological function is to participate in the production of bone marrow red blood cells, prevent malignant anemia, prevent brain nerve damage. Vitamin B 12 is one of the last B vitamins to be found so far. Vitamin B12 is a polycyclic compound containing 3 valent cobalt. Four reduced pyrrole rings are linked together to form a Golin macroring (similar to porphyrin), which is the core of vitamin B12 molecule. Therefore, compounds containing this ring are referred to as Golin-like. Vitamin B12 is a light red acicular crystal which is easily soluble in water and ethanol. It is most stable under the condition of weak acid pH 4.5 and 5.0, and decomposes in strong acid (pH < 2) or alkaline solution, which can be destroyed to some extent in the event of heat. But short time high temperature disinfection loss is small, encounter bright light or ultraviolet ray is easy to be destroyed. The loss of ordinary cooking process is about 30%.

Vöru Nafn:	VITAMÍN 12
CAS:	68-19-9
MF:	C63H88CoN14O14P
MW:	1355.37
EINECS:	200-680-0
B12 vítamín, sem er stutt í dag kallað VB12, einnig þekkt sem kóbalamín, og er eitt af B-vítamínum, er flokkur flókinna lífrænna efnasambanda sem innihalda kóbalt Corrin flokk og innihélt þrígildt kóbalt í svipuðu porfýrín Corrin plani í miðju hringsins .Það er stærsta og flóknasta vítamín sameindin sem hefur fundist. Það er líka eina vítamínið með málmjón. Kristallinn er rauður, það er einnig kallað rautt vítamín. Verksmiðjan inniheldur ekki VB12 og getur ekki framleitt VB12. Lifrin er besta uppspretta VB12, síðan úr mjólk, kjöti, eggjum, fiski og svo framvegis. VB12 er nauðsynlegt kóensím við myndun RNA og DNA. Skortur á VB12 in vivo getur valdið sjúklegum breytingum á taugakerfinu svo sem útlægum taugum og miðtaugakerfi.