يستعمل دواء ب12 اس ار 1000 ميكرو 20 كبسولةb12 sr 1000mcg 20 caps. vitamin b12 vitamin b12

description -cyanocobalamin (commonly known as vitamin b12) is the most chemically complex of all the vitamins. cyanocobalamin�s structure is based on a corrin ring which although similar to the porphyrin ring found in heme chlorophyll and cytochrome has two of the pyrrole rings directly bonded. the central metal ion is co (cobalt). cyanocobalamin cannot be made by plants or by animals as the only type of organisms that have the enzymes required for the synthesis of cyanocobalamin are bacteria and archaea. higher plants do not concentrate cyanocobalamin from the soil and so are a poor source of the substance as compared with animal tissues. cyanocobalamin is naturally found in foods including meat (especially liver and shellfish) eggs and milk products. - -mechanism of action vitamin b12 is used in the body in two forms: methylcobalamin and 5-deoxyadenosyl cobalamin. the enzyme methionine synthase needs methylcobalamin as a cofactor. this enzyme is involved in the conversion