Types and functions of vitamin K

K1 is synthesized by plants, such as green leafy plants such as alfalfa and spinach;K2 is synthesized by microorganisms. Human intestinal bacteria can also synthesize vitamin K2. Modern vitamin K can be artificially synthesized, such as vitamin K3, which is commonly used in clinical practice. Vitamin K is a derivative of 2-methyl-1,4-naphthoquinone. Vitamin K1 is a yellow oily substance, and K2 is a light yellow crystal, both of which are heat resistant, but are easily damaged by ultraviolet radiation, so they should be stored away from light. Synthetic K3 and K4 are water-soluble and can be used orally or for injection. Dicoumarol, an anticoagulant used clinically, has a chemical structure similar to vitamin K. It can resist the effect of vitamin K and can be used to prevent and treat the formation of blood clots. Vitamin K is closely related to the four coagulation factors synthesized by the liver: prothrombin, coagulation factors VII, IX and X. If vitamin K1 is lacking, the above four coagulation factors synthesized by the liver are abnormal protein molecules, and their ability to catalyze coagulation is greatly reduced. Vitamin K is known to be a cofactor in the gamma carboxylation of glutamic acid. If vitamin K is lacking, gamma-carboxylation of the above coagulation factors cannot proceed. In addition, these coagulation factors are reduced in the blood, causing coagulation delay and bleeding disorders. In addition, it is recognized that vitamin K is dissolved in the lipids of mitochondrial membranes and plays an electron transfer role. Vitamin K can increase intestinal peristalsis and secretion