Vitamin K
Phylloquinone (K1) & Menaquinone (K2)
Description: This is a fat soluble vitamin. Vitamin K1 may be found in green leafy vegetables. Vitamin K2, however, is produced by bacteria found as normal inhabitants of the intestines. Much of the vitamin K in tissues is from bacterial origin. The microbially synthesized vitamin K is absorbed in the colon (coprophagy may increase vitamin K absorption in dogs).
Properties: Role in normal blood clotting.
Activity: Vitamin K is necessary for carboxylation of proteins (factors II, VII, IX, X) which are important in the conversion of prothrombin to thrombin.