VB12(国外英文资料).docVIP

VB12(国外英文资料) Vitamin B12 Biological engineering 0712 xu wenjun 2007221061 Basic concepts Cyanocobalamin, also known as an animal protein factor, is a class of substances containing Cyanocobalamin active substances. It is the only water soluble vitamin that contains metal ions and is one of the essential vitamins in the body. Vitamin B12, a high melting point (320 ℃ without melting), odourless tasteless, no water content in the form of vitamin B12 dark red acicular crystal easy to moisture absorption, crystal water, stable in air. Vitamin B12 soluble in water, soluble in ethanol, insoluble in acetone, chloroform and ethyl ether, meet strong light can be decomposed, in 210 ~ 220 ℃ high temperature can change color, can be decomposed under strong acidic or alkaline. The weakest acid environment in pH4.5 ~ 5.0 is the most stable. The synthetic product of vitamin B12 is cyanocobalamin, which is formed when the cobalamin is isolated. It is a kind of red crystal, very stable, has been commercialized, and can be used for the reinforcement and nutritional supplement of food. Plant cells do not synthesize vitamin B12, so most plant foods do not contain vitamin B12, which is concentrated in animal tissues. The main physiological function of vitamin B12 2.1 improve the utilization rate of folic acid with folic acid synthesis of methionine by homocysteine (synthesis) and choline, produced in the process of purines and pyrimidines synthetic cyanocobalamin ShenJi cobalt precursor substances such as methyl amine and coenzyme B12, involved in many important compounds of methylation process. In the absence of vitamin B12, the reduction of activity in the methyl group from the methyl group of methyl hydrofolic acid, which makes folic acid an unusable form, leads to the deficiency of folic acid. To maintain the metabolism and function of the myelin sheath. Deficiency of vitamin B12 can cause neurological disorders, spinal cord degeneration, and can cause severe mental symptoms. Vitami