Fumaric acid, also called allomaleic acid, 2-butenedioic acid, boletic acid, or lichenic acid, is a colorless crystalline flammable carboxylic acid with a fruitlike taste and chemical formula ₂(C₂H)₂. Irritating maleic anhydride fumes are produced by its combustion. It is found in fumitory (Fumaria officinalis), bolete mushrooms (specifically Boletus fomentarius var. pseudo-igniarius), lichen, and Iceland moss .

Fumaric acid is an acid used in the manufacture of polyester resins and polyhydric alcohols, as a mordant for dyes, or as a flavoring. It is a common component of food additives and dietary supplements, and is sometimes used as a substitute for tartaric acid in beverages or baking powder.

Biology

Related to malic acid, fumaric acid is used by cells to produce energy from food. Human skin naturally produces fumaric acid when exposed to sunlight.

Medicine

Fumaric acid esters are sometimes used to treat psoriasis, as it has been suggested that the condition is caused by an impairment of fumaric acid production in the skin. A starting dose is 60-105mg daily, which may be gradually increased to as much as 1,290mg per day. Side effects include kidney or gastrointestinal disorders, as well as skin flushing; these are mainly caused by excess intake. Decreased white blood cell counts have been reported with prolonged use.

See also

• dermatology
• photosynthesis