MOLECULE

Glucaric acid

Glucaric acid, also known as D-saccharic acid, belongs to the class of organic compounds known as glucuronic acid derivatives. Glucuronic acid derivatives are compounds containing a glucuronic acid moiety (or a derivative), which consists of a glucose moiety with the C6 carbon oxidized to a carboxylic acid. Glucaric acid is very soluble in water, and relatively neutral. Glucaric acid exists in all living organisms, ranging from bacteria to humans. In mammals, D-glucaric acid is an end product of the D-glucuronic acid pathway. The glucuronic acid pathway catalyzes the conversion of glucose to glucuronic acid, ascorbic acid, and pentoses. Like the pentose phosphate pathway, this pathway provides biosynthetic precursors and inter-converts some less common sugars to ones that can be metabolized. D-glucaric acid is particularly abundant in fruits and vegetables, with the highest concentrations found in grapefruits, apples, oranges, and cruciferous vegetables. The D-glucaric acid content in fruits and vegetables ranges from about 0.1 g/kg in grapes and lettuce to about 3.5 g/kg in apples and broccoli. Glucaric acid is available as a dietary supplement in the form of calcium D-glucarate and has been studied for therapeutic purposes including cholesterol reduction and cancer chemotherapy (PMID: 12747003; PMID: 18772850). Industrially, D-glucaric acid produced from oxidizing D-glucose has been successfully utilized to produce a hydroxylated nylon, resulting in a presumably biodegradable nylon fiber. Glucaric acid’s sodium salt is used in dishwasher detergents. The acid acts as a chelating agent that ties up the hard-water calcium and magnesium ions to make the detergents more efficient. Glucaric acid is also a powerful corrosion inhibitor and is used in many applications where water contacts metal surfaces.