Identification of photoproducts of folic acid and its degradation pathways in aqueous solution.

The UV irradiated aqueous solutions of folic acid at pH 2-10 degrade to give pterin-6-carboxylic acid and p-aminobenzoyl-L-glutamic acid under aerobic conditions. These photoproducts have been identified by TLC, HPLC and Spectrophotometric techniques. A reaction scheme for the photodegradation pathways of folic acid leading to the formation of the photoproducts in acid and alkaline media has been proposed which involves the participation of an enamine intermediate.