Meconic acid, also known as acidum meconicum and poppy acid, is a chemical substance found in certain plants of the poppy family, Papaveraceae, such as '' Papaver somniferum'' (opium poppy) and '' Papaver bracteatum''. Meconic acid constitutes about 5% of

opium Opium (or poppy tears, scientific name: ''Lachryma papaveris'') is dried latex obtained from the seed capsules of the opium poppy ''Papaver somniferum''. Approximately 12 percent of opium is made up of the analgesic alkaloid morphine, which i ...

and can be used as an analytical marker for the presence of opium. Meconic acid has erroneously been described as a mild

narcotic The term narcotic (, from ancient Greek ναρκῶ ''narkō'', "to make numb") originally referred medically to any psychoactive compound with numbing or paralyzing properties. In the United States, it has since become associated with opiates ...

, but it has little or no physiological activity, and is not used medicinally. Meconic acid forms salts with alkaloids and metals. These salts as well as meconic acid esters are called meconates. Meconic acid was first isolated by Friedrich Sertürner in 1805.Friedrich Sertürner (1805
(Untitled letter to the editor)
''Journal der Pharmacie für Aerzte, Apotheker und Chemisten'' (Journal of Pharmacy for Physicians, Apothecaries, and Chemists), 13 : 229–243. See also: Sertuerner (1817
"Ueber das Morphium, eine neue salzfähige Grundlage, und die Mekonsäure, als Hauptbestandtheile des Opiums"
(On morphine, a new salifiable .e., precipitable fundamental substance, and meconic acid, as principal components of opium), ''Annalen der Physik'', 55 : 56–89.

Chemistry

Meconic acid is a

dicarboxylic acid In organic chemistry, a dicarboxylic acid is an organic compound containing two carboxyl groups (). The general molecular formula for dicarboxylic acids can be written as , where R can be aliphatic or aromatic. In general, dicarboxylic acids show ...

. Its structure contains two

carboxylic acid In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic ...

groups (-COOH) and one keto group (=O) attached to a pyran ring. Meconic acid gives a red color with ferric chloride. Meconic acid is colorless and is only slightly soluble in water but readily soluble in alcohol.

References

* {{Components of opium Dicarboxylic acids 4-Pyrones Enols