Isocitric acid is a
structural isomer
In chemistry, a structural isomer (or constitutional isomer in the IUPAC nomenclature) of a compound is a compound that contains the same number and type of atoms, but with a different connectivity (i.e. arrangement of bonds) between them. The ...
of
citric acid
Citric acid is an organic compound with the formula . It is a Transparency and translucency, colorless Weak acid, weak organic acid. It occurs naturally in Citrus, citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, ...
. Since citric acid and isocitric acid are structural isomers, they share similar physical and chemical properties. Due to these similar properties, it is difficult to separate the isomers.
Salts and
ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...
s of isocitric acid are known as isocitrates. The isocitrate anion is a substrate of the
citric acid cycle
The citric acid cycle—also known as the Krebs cycle, Szent–Györgyi–Krebs cycle, or TCA cycle (tricarboxylic acid cycle)—is a series of chemical reaction, biochemical reactions that release the energy stored in nutrients through acetyl-Co ...
. Isocitrate is formed from
citrate with the help of the
enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...
aconitase, and is acted upon by
isocitrate dehydrogenase.
Isocitric acid is commonly used as a marker to detect the authenticity and quality of fruit products, most often citrus juices. In authentic orange juice, for example, the ratio of citric acid to
D-isocitric acid is usually less than 130. An isocitric acid value higher than this may be indicative of fruit juice adulteration.
Isocitric acid has largely been used as a biochemical agent due to limited amounts.
However, isocitric acid has been shown to have pharmaceutical and therapeutic effects. Isocitric acid has been shown to effectively treat iron deficient anemia.
Additionally, isocitric acid could be used to treat
Parkinson's disease
Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become ...
.
''
Yarrowia lipolytica'' can be used to produce isocitric acid and is inexpensive compared to other methods. Furthermore, other methods produce unequal amounts of citric acid to isocitric acid ratio, mostly producing citric acid. Use of ''Yarrowia lipolytica'' produces a better yield, making equal amounts of citric acid to isocitric acid.
Interactive pathway map
See also
*
Citric acid
Citric acid is an organic compound with the formula . It is a Transparency and translucency, colorless Weak acid, weak organic acid. It occurs naturally in Citrus, citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, ...
, also
fluorocitric acid and
chlorocitric acid
*
Tartaric acid
*
Malic acid
Malic acid is an organic compound with the molecular formula . It is a dicarboxylic acid that is made by all living organisms, contributes to the sour taste of fruits, and is used as a food additive. Malic acid has two stereoisomeric forms ( ...
References
{{DEFAULTSORT:Isocitric Acid
Alpha hydroxy acids
Tricarboxylic acids
Citric acid cycle compounds
Aldols