Vitamin K is also required for the synthesis of other proteins found in plasma, bone and kidney. Vitamin K was discovered in 1935 by Henrik Dam as a fat soluble compound that prevented hemorrhagic disease in chicken.
There are two different forms of vitamin K:
*Vitamin K1
*Vitamin K2
Phylloquinone (vitamin K1), is the only form found in plans and is the primary dietary source of vitamin K.
Vitamin K1 is freely available in green vegetables particularly in alfalfa, cereals and animal food. The vitamin also called Mephyton. Thus vitamin K1 is 2 methyl, 3 phytyl-1,4 naphthoquinone.
It is a light yellow oil. This form of vitamin also found in vitamin K supplements and is often given to infants to prevent bleeding.
Menaquinone or vitamin K2, is a product of bacteria metabolism and makes only a minor contribution to vitamin K intake. Its absorption appears t be limited.
Another one is vitamin K3. It is 2-methyl, 1-4 naphthoquinone without any side chain or OH group. Also known as menadione, is synthetic analogue of vitamin K. This form of vitamin is neither found naturally in food nor made by intestinal bacteria but is produced commercially.
Types of vitamin K
