# Protocatechuic acid > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Protocatechuic_acid > Markdown URL: https://mediated.wiki/source/Protocatechuic_acid.md > Source: https://en.wikipedia.org/wiki/Protocatechuic_acid > Source revision: 1340232706 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{chembox | Watchedfields = changed | verifiedrevid = 477165260 | ImageFile=Protocatechusäure.svg | ImageSize=120px | PIN=3,4-Dihydroxybenzoic acid | ImageFile1 = 3,4-Dihydroxybenzoic acid.jpg | OtherNames = 3,4-Dihydroxybenzoic acid
PCA
Protocatechuate |Section1={{Chembox Identifiers | CASNo_Ref = {{cascite|correct|CAS}} | CASNo=99-50-3 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = 36R5QJ8L4B | PubChem=72 | ChEMBL_Ref = {{ebicite|correct|EBI}} | ChEMBL = 37537 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 71 | DrugBank_Ref = {{drugbankcite|correct|drugbank}} | DrugBank = DB03946 | EINECS = 202-760-0 | KEGG = C00230 | 3DMet = B00064 | RTECS = UL0560000 | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEBI = 36062 | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | StdInChI = 1S/C7H6O4/c8-5-2-1-4(7(10)11)3-6(5)9/h1-3,8-9H,(H,10,11) | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = YQUVCSBJEUQKSH-UHFFFAOYSA-N | SMILES=C1=CC(=C(C=C1C(=O)O)O)O }} |Section2={{Chembox Properties | Properties_ref={{cite book |editor=Haynes, William M. |date=2016 |title=CRC Handbook of Chemistry and Physics |edition=97th |publisher=[CRC Press](/source/CRC_Press) |chapter=3 |page=190 |url=https://ia800704.us.archive.org/27/items/CRCHandbookOfChemistryAndPhysics97thEdition2016/CRC%20Handbook%20of%20Chemistry%20and%20Physics%20-%2097th%20Edition%20%282016%29.pdf?page=3-190 |isbn=9781498754293}} | C=7 |H=6 |O=4 | Appearance= light brown solid | Density={{val|1.524|u=g/cm3}} ({{convert|4|C|F K}}) | MeltingPtC= 202 | MeltingPt_ref = | BoilingPtC = | Solubility= {{ubl |{{val|18|u=g/L}} ({{convert|14|C|F K}}) |{{val|271|u=g/L}} ({{convert|80|C|F K}}){{cite book |editor=Haynes, William M. |date=2016 |title=CRC Handbook of Chemistry and Physics |edition=97th |publisher=[CRC Press](/source/CRC_Press) |chapter=5 |url=https://ia800704.us.archive.org/27/items/CRCHandbookOfChemistryAndPhysics97thEdition2016/CRC%20Handbook%20of%20Chemistry%20and%20Physics%20-%2097th%20Edition%20%282016%29.pdf |isbn=9781498754293}}{{rp|5-148}} }} | Solubility1 = very soluble | Solvent1 = ethanol | Solubility2 = soluble | Solvent2 = diethyl ether | pKa = {{ubl |4.48 |8.83 |12.6{{rp|5-91}} }} }} |Section3={{Chembox Hazards | ExternalSDS = [http://www.sigmaaldrich.com/MSDS/MSDS/DisplayMSDSPage.do?country=PL&language=EN-generic&productNumber=37580&brand=ALDRICH&PageToGoToURL=http%3A//www.sigmaaldrich.com/catalog/product/aldrich/37580%3Flang%3Dpl MSDS] | MainHazards= | FlashPt= | AutoignitionPt = | NFPA-H = 2 | NFPA-F = 0 | NFPA-R = 0 }} |Section8={{Chembox Related |OtherCompounds = {{ubl |[2,3-Dihydroxybenzoic acid](/source/2%2C3-Dihydroxybenzoic_acid) |[2,4-Dihydroxybenzoic acid](/source/2%2C4-Dihydroxybenzoic_acid) |[2,5-Dihydroxybenzoic acid](/source/2%2C5-Dihydroxybenzoic_acid) |[2,6-Dihydroxybenzoic acid](/source/2%2C6-Dihydroxybenzoic_acid) |[3,5-Dihydroxybenzoic acid](/source/3%2C5-Dihydroxybenzoic_acid) |[Ethyl protocatechuate](/source/Ethyl_protocatechuate) }} }} }} thumb|right|UV visible spectrum of protocatechuic acid '''Protocatechuic acid''' ('''PCA''') is a [dihydroxybenzoic acid](/source/dihydroxybenzoic_acid), a type of phenolic acid. It is a major metabolite of antioxidant [polyphenol](/source/polyphenol)s found in [green tea](/source/green_tea). It has mixed effects on normal and cancer cells in ''[in vitro](/source/in_vitro)'' and ''[in vivo](/source/in_vivo)'' studies.{{cite journal |last1=Lin |first1=H.-H. |last2=Chen |first2=J.-H. |last3=Huang |first3=C.-C. |last4=Wang |first4=C.-J. |title=Apoptotic effect of 3,4-dihydroxybenzoic acid on human gastric carcinoma cells involving JNK/p38 MAPK signaling activation |journal= International Journal of Cancer |volume=120 |issue=11 |pages=2306–2316 |date=June 2007 |pmid=17304508 |doi=10.1002/ijc.22571 |doi-access=free }} It is produced commercially from [vanillin](/source/vanillin).{{Ullmann| doi=10.1002/14356007.a13_519| chapter=Hydroxycarboxylic Acids, Aromatic|year=2000| last1=Ritzer| first1=Edwin| last2=Sundermann| first2=Rudolf| isbn=3527306730}} == Biological effects == Protocatechuic acid (PCA) is [antioxidant](/source/antioxidant) and [anti-inflammatory](/source/anti-inflammatory). 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.{{cite journal |last1=Liu |first1=C.-L. |last2=Wang |first2=J.-M. |last3=Chu |first3=C.-Y. |title=In vivo protective effect of protocatechuic acid on ''tert''-butyl hydroperoxide-induced rat hepatotoxicity |journal=Food and Chemical Toxicology |volume=40 |pages=635–41 |year=2002 |pmid=11955669 |last4=Cheng |first4=M.-T. |last5=Tseng |first5=T.-H. |issue=5 |doi=10.1016/s0278-6915(02)00002-9}} PCA has been reported to induce [apoptosis](/source/apoptosis) of human [leukemia](/source/leukemia) cells, as well as malignant HSG1 cells taken from human oral cavities,{{cite journal |last1=Babich |first1=H. |last2=Sedletcaia |first2=A. |last3=Kenigsberg |first3=B. |title=''In vitro'' cytotoxicity of protocatechuic acid to cultured human cells from oral tissue: involvement in oxidative stress |journal=Pharmacology & Toxicology |volume=91 |issue=5 |pages=245–253 |date=November 2002 |pmid=12570031 |doi=10.1034/j.1600-0773.2002.910505.x |doi-access=free }} but PCA was found to have mixed effects on [TPA](/source/12-O-Tetradecanoylphorbol-13-acetate)-induced mouse skin tumours. Depending on the amount of PCA and the time before application, PCA could reduce or enhance tumour growth.{{cite journal |last1=Nakamura |first1=Y. |last2=Torikai |first2=K. |last3=Ohto |first3=Y. |last4=Murakami |first4=A. |last5=Tanaka |first5=T. |last6=Ohigashi |first6=H. |title=A simple phenolic antioxidant protocatechuic acid enhances tumor promotion and oxidative stress in female ICR mouse skin: dose- and timing-dependent enhancement and involvement of bioactivation by tyrosinase |journal=Carcinogenesis |volume=21 |issue=10 |pages=1899–1907 |date=October 2000 |pmid=11023549 |doi= 10.1093/carcin/21.10.1899|doi-access=free }} Similarly, PCA was reported to increase proliferation and inhibit apoptosis of neural [stem cell](/source/stem_cell)s.{{cite journal |last1=Guan |first1=S. |last2=Ge |first2=D. |last3=Liu |first3=T. Q. |last4=Ma |first4=X.-H. |last5=Cui |first5=Z.-F. |date=March 2009 |title= Protocatechuic acid promotes cell proliferation and reduces basal apoptosis in cultured neural stem cells|journal= Toxicology in Vitro|volume= 23|issue= 2|pages=201–208 |pmid= 19095056 |doi= 10.1016/j.tiv.2008.11.008|bibcode=2009ToxVi..23..201G }} In an ''in vitro'' model using [HL-60](/source/HL-60) [leukemia](/source/leukemia) cells, protocatechuic acid showed an antigenotoxic effect and tumoricidal activity.{{cite journal|last1=Anter |first1=J. |last2=Romero Jiménez |first2=M. |last3=Fernández Bedmar |first3=Z. |last4=Villatoro Pulido |first4=M. |last5=Analla |first5=M. |last6=Alonso Moraga |first6=A. |last7=Muñoz Serrano |first7=A. |title=Antigenotoxicity, cytotoxicity, and apoptosis induction by apigenin, bisabolol, and protocatechuic acid |journal=Journal of Medicinal Food |date=March 2011 |volume=14 |issue=3 |pages=276–283|doi=10.1089/jmf.2010.0139 |pmid=21182433 }} In two preclinical investigations, protocatechuic acid from ''[Hibiscus sabdariffa](/source/Hibiscus_sabdariffa)'' showed an excellent ability to effectively inhibit the replication of [herpes simplex virus type 2](/source/herpes_simplex_virus_type_2){{cite journal|last1=Hassan |first1=S. T. S. |last2=Švajdlenka |first2=E. |last3=Berchová-Bímová |first3=K. |title=''Hibiscus sabdariffa'' L. and its bioactive constituents exhibit antiviral activity against HSV-2 and anti-enzymatic properties against urease by an ESI–MS based assay |journal=Molecules |date=April 2017 |volume=22 |issue=5 |page=722|doi=10.3390/molecules22050722 |pmid=28468298 |pmc=6154344 |doi-access=free }} and to potently deactivate the catalytic activity of [urease](/source/urease).{{cite journal|last1=Hassan |first1=S. T. S. |last2=Švajdlenka |first2=E. |title=Biological evaluation and molecular docking of protocatechuic acid from ''Hibiscus sabdariffa'' L. as a potent urease inhibitor by an ESI–MS based method|journal=Molecules|date=October 2017 |volume=22 |issue=10 |page=1696|doi=10.3390/molecules22101696 |pmid=29019930 |pmc=6151788 |doi-access=free }} == Occurrence in nature == Protocatechuic acid can be isolated from the stem bark of ''[Boswellia dalzielii](/source/Boswellia_dalzielii)''.{{cite journal|title=Antibacterial phenolics from ''Boswellia dalzielii'' |last1=Alemika |first1=T. E. |last2=Onawunmi |first2=G. O. |last3=Olugbade |first3=T. O. |journal=Nigerian Journal of Natural Products and Medicines |date=2006 |volume=10 |pages=108–110 |url=http://dspace.unijos.edu.ng/handle/10485/1174 |archive-url=https://web.archive.org/web/20130730080304/http://dspace.unijos.edu.ng/handle/10485/1174 |url-status=dead |archive-date=2013-07-30 |access-date=2013-07-30 }} and from leaves of ''[Diospyros melanoxylon](/source/Diospyros_melanoxylon)''.{{cite journal|last1=Mallavadhani |first1=U. V. |last2=Mahapatra |first2=A. |title=A new aurone and two rare metabolites from the leaves of ''Diospyros melanoxylon'' |journal=Natural Product Research |date=2005 |volume=19 |issue=1 |pages=91–97|doi=10.1080/14786410410001704705 |pmid=15700652 |s2cid=35200920 }} The hardening of the protein component of [insect cuticle](/source/insect_cuticle) 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](/source/ootheca), the phenolic substance concerned is protocatechuic acid.{{Cite journal | last1 = Hackman | first1 = R. H. | last2 = Pryor | first2 = M. G. | last3 = Todd | first3 = A. R. | title = The occurrence of phenolic substances in arthropods | journal = The Biochemical Journal | volume = 43 | issue = 3 | pages = 474–477 | year = 1948 | pmid = 16748434 | pmc = 1274717 | doi=10.1042/bj0430474 }} === In foods === [Açaí oil](/source/A%C3%A7a%C3%AD_oil), obtained from the fruit of the [açaí palm](/source/a%C3%A7a%C3%AD_palm) (''Euterpe oleracea''), is rich in protocatechuic acid ({{val|630|36|u=mg/kg}}).{{cite journal |journal = Journal of Agricultural and Food Chemistry |date=June 2008 | volume = 56 | issue = 12 | pages = 4631–4636 | title = Chemical composition, antioxidant properties, and thermal stability of a phytochemical enriched oil from Açaí (''Euterpe oleracea'' Mart.) |pmid = 18522407| doi = 10.1021/jf800161u |last1=Pacheco Palencia |first1=L. A. |last2=Mertens-Talcott |first2=S |last3=Talcott |first3=S. T. }} 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](/source/Allium_cepa)'' (17,540 ppm).{{Cite web |url=http://www.ars-grin.gov/cgi-bin/duke/highchem.pl |title=Chemical Query |access-date=2011-09-25 |archive-url=https://web.archive.org/web/20130616093128/http://www.ars-grin.gov/cgi-bin/duke/highchem.pl |archive-date=2013-06-16 |url-status=dead }} PCA occurs in [roselle](/source/Roselle_(plant)) (''Hibiscus sabdariffa''), which is used worldwide as a food and beverage. Protocatechuic acid is also found in mushrooms such as ''[Agaricus bisporus](/source/Agaricus_bisporus)''{{cite journal |last1=Delsignore |first1=A |last2=Romeo. |first2=F. |last3=Giaccio |first3=M. |title=Content of phenolic substances in basidiomycetes |journal=Mycological Research |volume=101 |pages=552–556 |year=1997 |doi=10.1017/S0953756296003206 |issue=5}} or ''[Phellinus linteus](/source/Phellinus_linteus)''.{{cite journal |doi=10.1248/bpb.31.1968 |last1=Lee |first1=Y.-S. |last2=Kang |first2=Y. H. |last3=Jung |first3=J. Y. |display-authors=etal |title=Protein glycation inhibitors from the fruiting body of ''Phellinus linteus'' |journal=Biological & Pharmaceutical Bulletin |volume=31 |issue=10 |pages=1968–72 |date=October 2008 |pmid=18827365 |doi-access=free }} 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.{{Cite journal|last1=Li|first1=Xican|last2=Wang|first2=Xiaozhen|last3=Chen|first3=Dongfeng|last4=Chen|first4=Shuzhi|date=2011-07-31|title=Antioxidant Activity and Mechanism of Protocatechuic Acid in vitro|url=https://ffhdj.com/index.php/ffhd/article/view/127|journal=Functional Foods in Health and Disease|volume=1|issue=7|pages=232|doi=10.31989/ffhd.v1i7.127|issn=2160-3855|doi-access=free}} == Metabolism == Protocatechuic acid is one of the main catechins [metabolite](/source/metabolite)s found in humans after consumption of [green tea](/source/green_tea) infusions.{{cite journal | last1 = Pietta | first1 = P. G. | last2 = Simonetti | first2 = P. | last3 = Gardana | first3 = C. | last4 = Brusamolino | first4 = A. | last5 = Morazzoni | first5 = P. | last6 = Bombardelli | first6 = E. | year = 1998 | title = Catechin metabolites after intake of green tea infusions | journal = BioFactors | volume = 8 | issue = 1–2| pages = 111–118 | doi = 10.1002/biof.5520080119 | pmid=9699018| s2cid = 37684286 }} === Enzymes === ;Biosynthesis enzymes * [3-dehydroshikimate dehydratase](/source/3-dehydroshikimate_dehydratase) * [(3''S'',4''R'')-3,4-dihydroxycyclohexa-1,5-diene-1,4-dicarboxylate dehydrogenase](/source/(3S%2C4R)-3%2C4-dihydroxycyclohexa-1%2C5-diene-1%2C4-dicarboxylate_dehydrogenase) * [terephthalate 1,2-''cis''-dihydrodiol dehydrogenase](/source/terephthalate_1%2C2-cis-dihydrodiol_dehydrogenase) * [3-hydroxybenzoate 4-monooxygenase](/source/3-hydroxybenzoate_4-monooxygenase) * [4-hydroxybenzoate 3-monooxygenase (NAD(P)H)](/source/4-hydroxybenzoate_3-monooxygenase_(NAD(P)H)) * [4-sulfobenzoate 3,4-dioxygenase](/source/4-sulfobenzoate_3%2C4-dioxygenase) * [vanillate monooxygenase](/source/vanillate_monooxygenase) * [3,4-dihydroxyphthalate decarboxylase](/source/3%2C4-dihydroxyphthalate_decarboxylase) * [4,5-dihydroxyphthalate decarboxylase](/source/4%2C5-dihydroxyphthalate_decarboxylase) center|thumb|600px|Protocatechuic acid biosynthesis ; Degradation enzymes * The enzyme [protocatechuate decarboxylase](/source/protocatechuate_decarboxylase) uses 3,4-dihydroxybenzoate to produce [catechol](/source/catechol) and {{chem2|CO2}}. * The enzyme [protocatechuate 3,4-dioxygenase](/source/protocatechuate_3%2C4-dioxygenase) uses 3,4-dihydroxybenzoate and oxygen to produce 3-carboxy-''cis'',''cis''-muconate.{{cite journal |last1= Fujisawa |first1= H. |last2= Hayaishi |first2= O. |title= Protocatechuate 3,4-Dioxygenase |journal= Journal of Biological Chemistry |date= 1968 |volume= 243 |issue= 10 |pages= 2673–2681 |doi= 10.1016/S0021-9258(18)93425-3 |doi-access= free }} {{chemrxn|width=40%| {{chemrxn/cpd|protocatechuic acid }} {{chemrxn/arw|fwd_in={{chem2|O2}} }} {{chemrxn/cpd|3-Carboxy-cis,cis-muconic acid|upright=2|caption=[3-carboxy-''cis'',''cis''-muconic acid](/source/3-Carboxy-cis%2Ccis-muconic_acid) }} }} == References == {{reflist}} {{Phenolic acid}} Category:Dihydroxybenzoic acids Category:Phenol antioxidants Category:Catechols --- Adapted from the Wikipedia article [Protocatechuic acid](https://en.wikipedia.org/wiki/Protocatechuic_acid) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Protocatechuic_acid?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.