Vitamin B12, also known as cobalami

Vitamin B12, also known as cobalamin, is the only vitamin containing metal elements. Vitamin B12 in nature is synthesized by microorganisms. Vitamin B12 is the only vitamin that needs the help of an intestinal secretion (endogenous factor) to be absorbed. Some people suffer from pernicious anemia due to gastrointestinal abnormalities and lack of this endogenous factor, even if they have sufficient dietary sources. There is basically no vitamin B12 in vegetable foods. It stays in the intestinal tract for a long time and takes about three hours (most water-soluble vitamins only take a few seconds) to be absorbed. The main physiological function of vitamin B12 is to participate in the production of bone marrow red blood cells and prevent pernicious anemia. Prevent brain nerve damage. Vitamin B12 is the latest vitamin found so far among B vitamins. Vitamin B12 is a polycyclic compound containing trivalent cobalt. Four reduced pyrrole rings are linked together to form a Golin macrocycle (similar to porphyrin), which is the core of vitamin B12 molecule. Therefore, compounds containing such a ring are all called golin-like. Vitamin B12 is a light red needle-like crystal, easily soluble in water and ethanol, and most stable under weak acid conditions with pH value of 4.5 ~ 5.0. it is decomposed in strong acid (pH