Menadione (Vitamin K3)
Menadione is a fat-soluble vitamin precursor that is converted into menaquinone in the liver. The primary known function of vitamin K is to assist in the normal clotting of blood, but it may also play a role in normal bone calcificaton. Vitamin K is primarily found in green leafy vegetables, but also in lesser amounts in some dairy products, meat, eggs, and fruits.
Menadione is found in all plant cells. It is also produced by some bacteria, including bacteria lining the gastro-intestinal tract of humans. Menadione is an electron acceptor used in respiration, photosynthesis and other processes. It acts as an electron acceptor when chlorophyll is raised to an excited state, allowing for a non-photochemical energy decrease for chlorophyll when it returns to its ground state. Menadione is a fat soluble vitamin (vitamin K3) and is necessary for the production of prothrombin and five other blood clotting factors in humans. It also regulates bone calcification.
Vitamin K1 and K2 are the naturally occurring types of vitamin K. The former, which is also known as phylloquinone, is synthesized by plants and can be found in such foods as spinach, broccoli, lettuce, and soybeans. The latter, sometimes alternatively referred to as menaquinone, is primarily produced by bacteria in the anterior part of the gut and the intestines. Vitamin K3, on the other hand, is one of the many manmade versions of vitamin K. Also called menadione, this yellowish, synthetic crystalline substance is converted into the active form of the K2 vitamin inside of the animal body. While a vitamin K deficiency can be dangerous, especially to infants that may easily suffer from extensive hemorrhaging, an overdose can be as equally detrimental. Newborns that are administered too great a dosage of vitamin K3 can suffer from kernicterus, a form of severe brain damage that may produce decreased movement, loss of appetite, seizures, deafness, mental retardation, and even death. This condition is associated with an abnormally high concentration of bilirubin, a bile pigment, in the tissues of the brain, which can be caused by the presence of K3. For this reason, K3 is less often utilized medically than it was in former times.
Chemical Formula: C11H8O2
Other names: 2-Methyl-1,4-naphthalendione, Vitamine K3