Folic acid, a member of the B-complex vitamins, is a water-soluble vitamin that is unstable in heat and light. Dietary supplies of folic acid are in the polyglutamate form which is then converted in the wall of the small intestine to the monoglutamate form before being absorbed into the bloodstream. Folic acid is synthesized by intestinal bacteria in the large intestine (colon), and absorption occurs in the upper part of the small intestine and is stored in the liver. Folic acid can be chemically synthesized for industrial production.