Chlorogenic acid
Encyclopedia
Chlorogenic acid is a hydroxycinnamic acid
, a member of a family of naturally occurring organic compounds. These are ester
s of polyphenolic caffeic acid
and cyclitol (-)-quinic acid
. It is an important biosynthetic intermediate. It also is one of the phenol
s found in coffee
, bamboo Phyllostachys edulis
, as well as many other plants. This compound, long known as an antioxidant
, also slows the release of glucose
into the bloodstream after a meal.
formed between caffeic acid
and
(L)-quinic acid
(1L-1(OH),3,4/5-tetrahydroxycyclohexanecarboxylic acid
).
Isomerisation of chlorogenic acid have been reported with 3 isomerisations of the quinic acid in position 3, (3-CQA), 4 (4-CQA) and 5 (5-CQA). Isomerisation at position 1 has not yet been reported.
biosynthesis
.
and an inhibitor of the tumor promoting activity of phorbol
esters. Chlorogenic acid and caffeic acid are antioxidants in vitro
and might therefore contribute to the prevention of Type 2 Diabetes Mellitus and cardiovascular disease. It is claimed to have antiviral, antibacterial and antifungal effects with relatively low toxicity and side effects, alongside properties that do not lead to antimicrobial resistance. Potential uses are suggested in pharmaceuticals, foodstuffs, feed additives, and cosmetics.
Chlorogenic acid is marketed under the tradename Svetol in Norway and the United Kingdom as a food active ingredient used in coffee, chewing gum, and mints to promote weight reduction.
to inhibit the hydrolysis
of the enzyme glucose-6-phosphatase in an irreversible fashion. This mechanism allows chlorogenic acid to reduce hepatic glycogenolysis
(transformation of glycogen into glucose) and to reduce the absorption of new glucose
. In addition, in vivo
studies on animal subjects have demonstrated that the administration of chlorogenic acid lessens the hyperglycemic peak
resulting from the glycogenolysis brought about by the administering of glucagon, a hyperglycemiant hormone. The studies also confirmed a reduction in blood glucose levels and an increase in the intrahepatic concentrations of glucose-6-phosphate and of glycogen
.
Hydroxycinnamic acid
Hydroxycinnamic acids are a class of polyphenols having a C6-C3 skeleton. These compounds are hydroxy derivatives of cinnamic acid.In the category of phytochemicals that can be found in food, there are :* Alpha-cyano-4-hydroxycinnamic acid...
, a member of a family of naturally occurring organic compounds. These are ester
Ester
Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...
s of polyphenolic caffeic acid
Caffeic acid
Caffeic acid is a hydroxycinnamic acid, a naturally occurring organic compound. This yellow solid consists of both phenolic and acrylic functional groups...
and cyclitol (-)-quinic acid
Quinic acid
Quinic acid is a cyclitol, a cyclic polyol. It is a crystalline acid obtained from cinchona bark, coffee beans, and other plant products and made synthetically by hydrolysis of chlorogenic acid. Quinic acid is also implicated in the perceived acidity of coffee...
. It is an important biosynthetic intermediate. It also is one of the phenol
Phenol
Phenol, also known as carbolic acid, phenic acid, is an organic compound with the chemical formula C6H5OH. It is a white crystalline solid. The molecule consists of a phenyl , bonded to a hydroxyl group. It is produced on a large scale as a precursor to many materials and useful compounds...
s found in coffee
Coffee
Coffee is a brewed beverage with a dark,init brooo acidic flavor prepared from the roasted seeds of the coffee plant, colloquially called coffee beans. The beans are found in coffee cherries, which grow on trees cultivated in over 70 countries, primarily in equatorial Latin America, Southeast Asia,...
, bamboo Phyllostachys edulis
Phyllostachys edulis
Phyllostachys edulis is a bamboo species belonging to the genus Phyllostachys. The edulis part of the Latin name is a reference to the fact that it produces edible shoots. This bamboo can reach heights of up to 70 feet ....
, as well as many other plants. This compound, long known as an antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
, also slows the release of glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
into the bloodstream after a meal.
Chemical properties
Structurally, chlorogenic acid (CGA) is the esterEster
Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...
formed between caffeic acid
Caffeic acid
Caffeic acid is a hydroxycinnamic acid, a naturally occurring organic compound. This yellow solid consists of both phenolic and acrylic functional groups...
and
(L)-quinic acid
Quinic acid
Quinic acid is a cyclitol, a cyclic polyol. It is a crystalline acid obtained from cinchona bark, coffee beans, and other plant products and made synthetically by hydrolysis of chlorogenic acid. Quinic acid is also implicated in the perceived acidity of coffee...
(1L-1(OH),3,4/5-tetrahydroxycyclohexanecarboxylic acid
Carboxylic acid
Carboxylic acids are organic acids characterized by the presence of at least one carboxyl group. The general formula of a carboxylic acid is R-COOH, where R is some monovalent functional group...
).
Isomerisation of chlorogenic acid have been reported with 3 isomerisations of the quinic acid in position 3, (3-CQA), 4 (4-CQA) and 5 (5-CQA). Isomerisation at position 1 has not yet been reported.
Biological importance
Chlorogenic acid is an important intermediate in ligninLignin
Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. The term was introduced in 1819 by de Candolle and is derived from the Latin word lignum, meaning wood...
biosynthesis
Biosynthesis
Biosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...
.
Potential as antioxidants
It is also an antioxidantAntioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
and an inhibitor of the tumor promoting activity of phorbol
Phorbol
Phorbol is a natural, plant-derived organic compound. It is a member of the tigliane family of diterpenes. It was first isolated in 1934 as the hydrolysis product of croton oil, which is derived from the seeds of Croton tiglium. Phorbol's structure was determined in 1967...
esters. Chlorogenic acid and caffeic acid are antioxidants in vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
and might therefore contribute to the prevention of Type 2 Diabetes Mellitus and cardiovascular disease. It is claimed to have antiviral, antibacterial and antifungal effects with relatively low toxicity and side effects, alongside properties that do not lead to antimicrobial resistance. Potential uses are suggested in pharmaceuticals, foodstuffs, feed additives, and cosmetics.
Chlorogenic acid is marketed under the tradename Svetol in Norway and the United Kingdom as a food active ingredient used in coffee, chewing gum, and mints to promote weight reduction.
Recent studies
Chlorogenic acid has been proven in animal studies in vitroIn vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
to inhibit the hydrolysis
Hydrolysis
Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
of the enzyme glucose-6-phosphatase in an irreversible fashion. This mechanism allows chlorogenic acid to reduce hepatic glycogenolysis
Glycogenolysis
Glycogenolysis is the conversion of glycogen polymers to glucose monomers. Glycogen is catabolized by removal of a glucose monomer through cleavage with inorganic phosphate to produce glucose-1-phosphate...
(transformation of glycogen into glucose) and to reduce the absorption of new glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
. In addition, in vivo
In vivo
In vivo is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro controlled environment. Animal testing and clinical trials are two forms of in vivo research...
studies on animal subjects have demonstrated that the administration of chlorogenic acid lessens the hyperglycemic peak
Hyperglycemia
Hyperglycemia or Hyperglycæmia, or high blood sugar, is a condition in which an excessive amount of glucose circulates in the blood plasma. This is generally a glucose level higher than 13.5mmol/l , but symptoms may not start to become noticeable until even higher values such as 15-20 mmol/l...
resulting from the glycogenolysis brought about by the administering of glucagon, a hyperglycemiant hormone. The studies also confirmed a reduction in blood glucose levels and an increase in the intrahepatic concentrations of glucose-6-phosphate and of glycogen
Glycogen
Glycogen is a molecule that serves as the secondary long-term energy storage in animal and fungal cells, with the primary energy stores being held in adipose tissue...
.
Isomers
Isomers of chlorogenic acid exist and are found in potatoes. They are 4-O-caffeoylquinic acid (crypto-chlorogenic acid), 5-O-caffeoylquinic acid (neo-chlorogenic acid), 3,4-dicaffeoylquinic acid and 3,5-dicaffeoylquinic acid.External links
- http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=1794427&loc=ec_rcs