Vitamin K2, also known as menaquinone 7, is a fat-soluble Vitamin, commonly referred to as MK. It is important for the health of bone and cardiovascular. Vitamin K2 is generally subdivided into the short-chain menaquinones (with MK-4 as the most important member) and the long-chain menaquinones, of which MK-7, MK-8 and MK-9 are nutritionally the most recognized. The activity of vitamin K2 is related to the length of the side chain, the longer the side chain, the better the absorption, the higher the biological activity, and the longer the presence in the blood.