Vitamin K was discovered by Henrik Dam in Denmark as a result of studies of disorders of blood coagulation and he named it for its function Koagulation – in Danish/German- hence vitamin K. Vitamin K is a generic term for a group of naphthaquinone derivatives with characteristic anti haemorrhagic characterisics. (Gibney, 2002)
Green leafy vegetables are excellent sources of Vitamin K, one serving of spinach or two servings of broccoli provide four to five times the RDA. Sources of naturally occurring vitamin K are spinach, cabbage, lettuce, broccoli, kale,
eggs, oats and pork. Intestinal Bacteria (Sardesai, 2003, Osiecki, 2010)
Vitamin K depends on functioning liver tissue to be converted to its active form. It exist naturally in two fat soluble forms of, Vitamin K1 which occurs in green plants and was originally isolated from alfalfa and K2 which is manufactured by intestinal bacteria and was originally isolated from putrefied fish meal. In these natural forms, vitamin is not stable and is destroyed by oxidation. Vitamin K3 is synthetically produced, also fat soluble and known as menadione. Several water soluble and water miscible preparations with vitamin K activity also exist (Sardesai, 2003)
Vitamin K is essential in helping the blood clot, a function that ensures that we do not haemorrhage to death. Apart from this, Vitamin K is also important in the synthesis of proteins found in plasma, bone, kidneys and in cell growth. This is because Vitamin K functions as an essential cofactor for the enzyme carbolylase that converts specific glutamic acid residues of precursor proteins to ϒ=carboxyglutamic acid (GLA) residues in the new protein. The active form of the vitamin is the hydroquinone (Sardesai, 2003, WHO, 2004,Osiecki, 2010) Vitamin K2 is active in the process of bone formation by modifying the protein osteocalcin and giving it the ability to bind to calcium thus not only building the bone structure but...
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