Gluconic acid is an organic compound with molecular formula C6H12O7 and condensed structural formula HOCH2(CHOH)4COOH. In aqueous solution at neutral pH, carboxylic acid forms the gluconate ion and the salts of gluconic acid are also known as gluconates. Gluconic and gluconate salts occur widely in nature because such species arise from the oxidation of glucose. Gluconate esters can also be formed, such as quinine gluconate which is used for IM injections in the treatment of malaria.
The chemical structure of gluconic acid consists of a six-carbon chain with five hydroxyl groups terminating in a carboxylic acid group. In aqueous solution, gluconic acid exists in equilibrium with the cyclic ester Glucono delta lactone.
Occurrence and uses
Gluconic acid occurs naturally in fruit, honey, kombucha tea, and wine. As a food additive (E574), it is an acidity regulator. It is also used in cleaning products where it dissolves mineral deposits especially in alkaline solution. The gluconate anion chelates Ca2+, Fe2+, Al3+, and other heavy metals. Calcium gluconate is used to treat burns from hydrofluoric acid.