off-white to tan crystals or crystalline powder
An intermediate in the metabolism of tyrosine and phenylalanine. Occurs in plants and in the urine of alkaptonurics.
Homogentisic acid may be used as an analytical reference standard for the quantification of the analyte in the following:
- Urine matrices using reversed-phase liquid chromatography tandem mass spectrometry (LC-MS/MS).
- Strawberry tree honey samples using reversed phase-high performance liquid chromatography (RP-HPLC) and ion chromatography (IC).
It may also be used as an internal standard for the determination of ascorbic acid (AA) and uric acid (UA) in human plasma samples using high-pressure liquid chromatography–electrochemical detection (HPLC–ECD).
ChEBI: Homogentisic acid is a dihydroxyphenylacetic acid having the two hydroxy substituents at the 2- and 5-positions. It has a role as a human metabolite and a plant metabolite. It is a dihydroxyphenylacetic acid and a member of hydroquinones. It is functionally related to a phenylacetic acid. It is a conjugate acid of a homogentisate.
Homogentisic acid (HGA) is an intermediate formed during the catabolism of phenylalanine and tyrosine. Alkaptonuria, a metabolic disorder, is characterized by high levels of HGA in serum and urine due to the deficiency of the enzyme homogentisic acid oxidase, which is involved in the degradation of HGA.
Crystallise homogentisic acid from EtOH/CHCl3 or H2O (solubility is 85% at 25o). [Beilstein 10 IV 1506.]
