Hydroxycitric acid (HCA) is a derivative 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, ...
that is found in a variety of tropical plants including ''
Garcinia cambogia'' and ''
Hibiscus sabdariffa
Roselle (''Hibiscus sabdariffa'') is a species of flowering plant in the genus ''Hibiscus'' that is native to Africa, most likely West Africa. In the 16th and early 17th centuries it was spread to Asia and the West Indies, where it has since beco ...
''.
There are four isomers, (+)- and (-)-hydroxycitric acid, and (+)- and (-)-allo-hydroxycitric acid. The (-)-hydroxycitric acid isomer is the one found in ''
Garcinia
''Garcinia'' is a genus of flowering plants in the family (biology), family Clusiaceae native to the Sundaland bioregion of Asia, America, Australia, tropical and southern Africa, and Polynesia.
The number of species is disputed; Plants of the W ...
''.
Chemistry
Hydroxycitric acid as such cannot be isolated from garcinia fruits or hibiscus sabdariffa fruits. It exists in both the open and lactone forms. The presence of two chiral centres in the molecule is exploited to construct molecular skeletons that are otherwise difficult to synthesize, thus demonstrating the lactones use as chirons.
Biological effects
(-)-HCA is a competitive inhibitor of
ATP citrate lyase, which converts citrate into
oxaloacetate
Oxaloacetic acid (also known as oxalacetic acid or OAA) is a crystalline organic compound with the chemical formula HO2CC(O)CH2CO2H. Oxaloacetic acid, in the form of its conjugate base oxaloacetate, is a metabolic intermediate in many processes ...
and
acetyl CoA
Acetyl-CoA (acetyl coenzyme A) is a molecule that participates in many biochemical reactions in protein, carbohydrate and lipid metabolism. Its main function is to deliver the acetyl group to the citric acid cycle (Krebs cycle) to be oxidized fo ...
.
The reverse of this conversion is a step in 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 ...
.
Laboratory and animal studies of HCA have produced results that indicate a potential for modulation of lipid metabolism.
A meta-analysis published in 2010 revealed that gastrointestinal adverse effects were twice as likely for users of hydroxycitric acid. The use of HCA is contraindicated in people with
colitis
Colitis is swelling or inflammation
Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and ...
or
inflammatory bowel disease
Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine ...
.
Potential for liver damage
A 2024 review indicated that consuming foods or
dietary supplement
A dietary supplement is a manufactured product intended to supplement a person's diet by taking a pill (pharmacy), pill, capsule (pharmacy), capsule, tablet (pharmacy), tablet, powder, or liquid. A supplement can provide nutrients eithe ...
s containing hydroxycitric acid, such as
''Garcinia'' products, may cause
liver disease
Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common.
Liver diseases
File:Ground gla ...
.
References
{{DEFAULTSORT:Hydroxycitric Acid
Dietary supplements
Tricarboxylic acids
Alpha hydroxy acids