3,4-dihydroxybenzoate
   HOME

TheInfoList



OR:

Protocatechuic acid (PCA) is a
dihydroxybenzoic acid Dihydroxybenzoic acids (DHBA) are a type of phenolic acids. There are six main compounds, having all the same molecular formula C7H6O4. Those are: * 2,3-Dihydroxybenzoic acid (2-Pyrocatechuic acid or hypogallic acid) * 2,4-Dihydroxybenzoic acid ...
, a type of phenolic acid. It is a major metabolite of antioxidant
polyphenol Polyphenols () are a large family of naturally occurring phenols. They are abundant in plants and structurally diverse. Polyphenols include phenolic acids, flavonoids, tannic acid, and ellagitannin, some of which have been used historically as ...
s found in
green tea Green tea is a type of tea made from the leaves and buds of the '' Camellia sinensis'' that have not undergone the withering and oxidation process that creates oolong teas and black teas. Green tea originated in China in the late 1st millenn ...
. It has mixed effects on normal and cancer cells in ''
in vitro ''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...
'' and ''
in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, an ...
'' studies. It is produced commercially from
vanillin Vanillin is an organic compound with the molecular formula . It is a phenolic aldehyde. Its functional groups include aldehyde, hydroxyl, and ether. It is the primary component of the ethanolic extract of the vanilla bean. Synthetic vanillin ...
.


Biological effects

Protocatechuic acid (PCA) is
antioxidant Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants ...
and
anti-inflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation, fever or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs reduce pain by inhibiting mechan ...
. PCA extracted from ''Hibiscus sabdariffa'' protected against chemically induced liver toxicity ''in vivo''. ''In vitro'' testing documented antioxidant and anti-inflammatory activity of PCA, while liver protection ''in vivo'' was measured by chemical markers and histological assessment. PCA has been reported to induce
apoptosis Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...
of human
leukemia Leukemia ( also spelled leukaemia; pronounced ) is a group of blood cancers that usually begin in the bone marrow and produce high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or '' ...
cells, as well as malignant HSG1 cells taken from human oral cavities, but PCA was found to have mixed effects on TPA-induced mouse skin tumours. Depending on the amount of PCA and the time before application, PCA could reduce or enhance tumour growth. Similarly, PCA was reported to increase proliferation and inhibit apoptosis of neural
stem cell In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can change into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of cell ...
s. In an ''in vitro'' model using
HL-60 The HL-60 cell line is a human leukemia cell line that has been used for laboratory research on blood cell formation and physiology. HL-60 proliferates continuously in suspension culture in nutrient and antibiotic chemicals. The doubling time is ab ...
leukemia Leukemia ( also spelled leukaemia; pronounced ) is a group of blood cancers that usually begin in the bone marrow and produce high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or '' ...
cells, protocatechuic acid showed an antigenotoxic effect and tumoricidal activity. In two preclinical investigations, protocatechuic acid from ''
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 ...
'' showed an excellent ability to effectively inhibit the replication of
herpes simplex virus type 2 Herpes simplex virus 1 and 2 (HSV-1 and HSV-2) are two members of the human ''Herpesviridae'' family, a set of viruses that produce viral infections in the majority of humans. Both HSV-1 and HSV-2 are very common and contagious. They can be ...
and to potently deactivate the catalytic activity of
urease Ureases (), functionally, belong to the superfamily of amidohydrolases and phosphotriesterases. Ureases are found in numerous Bacteria, Archaea, fungi, algae, plants, and some invertebrates. Ureases are nickel-containing metalloenzymes of high ...
.


Occurrence in nature

Protocatechuic acid can be isolated from the stem bark of '' Boswellia dalzielii''. and from leaves of ''
Diospyros melanoxylon ''Diospyros melanoxylon'', the Coromandel ebony or East Indian ebony, is a species of flowering tree in the family Ebenaceae native to India and Sri Lanka; it has a hard, dry bark. Its common name derives from Coromandel, the coast of southe ...
''. The hardening of the protein component of
insect cuticle Arthropods are covered with a tough, resilient integument, cuticle or exoskeleton of chitin. Generally the exoskeleton will have thickened areas in which the chitin is reinforced or stiffened by materials such as minerals or hardened proteins. T ...
has been shown to be due to the tanning action of an agent produced by oxidation of a phenolic substance. In the analogous hardening of the cockroach
ootheca An ootheca (: oothecae ) is a type of egg capsule made by any member of a variety of species including mollusks (such as '' Turbinella laevigata''), mantises, and cockroaches. Etymology The word is a Latinized combination of ''oo-'', meaning " ...
, the phenolic substance concerned is protocatechuic acid.


In foods

Açaí oil Açaí oil is obtained from the fruit of ''Euterpe oleracea'' (açaí palm), which grows in the Amazon rainforest. The oil is rich in phenolic compounds similar in profile to the pulp itself, such as vanillic acid, syringic acid, p-hydroxybenzoic ...
, obtained from the fruit of the
açaí palm The açaí palm (, , from Nheengatu ''asai''), '' Euterpe oleracea'', is a species of palm tree (Arecaceae) cultivated for its fruit (açaí berries, or simply açaí), hearts of palm (a vegetable), leaves, and trunk wood. Global demand for th ...
(''Euterpe oleracea''), is rich in protocatechuic acid (). Protocatechuic acid also exists in the skins of some strains of onion as an antifungal mechanism, increasing endogenous resistance against smudge fungus. It is also found in ''
Allium cepa An onion (''Allium cepa'' , from Latin ), also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated species of the genus ''Allium''. The shallot is a botanical variety of the onion which was classified ...
'' (17,540 ppm). PCA occurs in roselle (''Hibiscus sabdariffa''), which is used worldwide as a food and beverage. Protocatechuic acid is also found in mushrooms such as ''
Agaricus bisporus ''Agaricus bisporus'', commonly known as the cultivated mushroom, is a basidiomycete mushroom native to grasslands in Eurasia and North America. It is cultivated in more than 70 countries and is one of the most commonly and widely consumed ...
'' or ''
Phellinus linteus ''Tropicoporus linteus'' is a tropical American mushroom. Its former name ''Phellinus linteus'' is applied wider, including to an East Asian mushroom. Taxonomy ''Polyporus linteus'' was named by Miles Joseph Berkeley and Moses Ashley Curtis an ...
''. PCA is regarded as an active component in traditional Chinese herbal medicine such as Stenoloma chusanum (L.) Ching, Ilex chinensis Sims, Cibotium barometz (L.) J.Sm.


Metabolism

Protocatechuic acid is one of the main catechins
metabolite In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...
s found in humans after consumption of
green tea Green tea is a type of tea made from the leaves and buds of the '' Camellia sinensis'' that have not undergone the withering and oxidation process that creates oolong teas and black teas. Green tea originated in China in the late 1st millenn ...
infusions.


Enzymes

;Biosynthesis enzymes * 3-dehydroshikimate dehydratase * (3''S'',4''R'')-3,4-dihydroxycyclohexa-1,5-diene-1,4-dicarboxylate dehydrogenase * terephthalate 1,2-''cis''-dihydrodiol dehydrogenase * 3-hydroxybenzoate 4-monooxygenase * 4-hydroxybenzoate 3-monooxygenase (NAD(P)H) * 4-sulfobenzoate 3,4-dioxygenase * vanillate monooxygenase * 3,4-dihydroxyphthalate decarboxylase * 4,5-dihydroxyphthalate decarboxylase ; Degradation enzymes * The enzyme protocatechuate decarboxylase uses 3,4-dihydroxybenzoate to produce
catechol Catechol ( or ), also known as pyrocatechol or 1,2-dihydroxybenzene, is an organic compound with the molecular formula . It is the ''ortho'' isomer of the three isomeric benzenediols. This colorless compound occurs naturally in trace amounts. It ...
and CO2. * The enzyme
protocatechuate 3,4-dioxygenase In enzymology, a protocatechuate 3,4-dioxygenase () is an enzyme that catalyzes the chemical reaction : 3,4-dihydroxybenzoate + O2 \rightleftharpoons 3-carboxy-cis,cis-muconate Thus, the two substrates of this enzyme are 3,4-dihydroxybenzoate (p ...
uses 3,4-dihydroxybenzoate and O2 to produce 3-carboxy-''cis'',''cis''-muconate.


See also

*
Ethyl protocatechuate Ethyl protocatechuate is a phenolic compound. It can be found in the peanut seed testa. It is also present in wine. It is the ethylic ester of protocatechuic acid. The compound is a prolyl 4-hydroxylase inhibitor and can be used to protect the my ...


References


Cited sources

* {{Phenolic acid Dihydroxybenzoic acids Phenol antioxidants Catechols