Caftaric acid

{{chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 396306810 | ImageFile = Caftaric acid.svg | ImageSize = 250 | PIN = (2''R'',3''R'')-2-{[(2''E'')-3-(3,4-Dihydroxyphenyl)prop-2-enoyl]oxy}-3-hydroxybutanedioic acid | OtherNames = Monocaffeyltartaric acid Butanedioic acid, 2-(3-(3,4-dihydroxyphenyl)-1-oxo-2-propenyl)-3-hydroxy-, (R-(R*,R*-(E)))- ''trans''-Caftaric acid ''cis''-Caftaric acid ''trans''-Caffeoyl tartaric acid ''cis''-Caffeoyl tartaric acid | Reference = |Section1={{Chembox Identifiers | PubChem = 6440397 | InChIKey = SWGKAHCIOQPKFW-JTNORFRNBW | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = SWGKAHCIOQPKFW-JTNORFRNSA-N | InChIKey1 = SWGKAHCIOQPKFW-JTNORFRNSA-N | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 4944664 | ChEMBL_Ref = {{ebicite|changed|EBI}} | ChEMBL = 558557 | CASNo_Ref = {{cascite|correct|CAS}} | CASNo = 67879-58-7 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = WCV7W3174L | MeSHName = caftaric+acid | InChI = 1S/C13H12O9/c14-7-3-1-6(5-8(7)15)2-4-9(16)22-11(13(20)21)10(17)12(18)19/h1-5,10-11,14-15,17H,(H,18,19)(H,20,21)/b4-2+/t10-,11-/m1/s1 | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | StdInChI = 1S/C13H12O9/c14-7-3-1-6(5-8(7)15)2-4-9(16)22-11(13(20)21)10(17)12(18)19/h1-5,10-11,14-15,17H,(H,18,19)(H,20,21)/b4-2+/t10-,11-/m1/s1 | SMILES = O=C(O)[C@H](O)[C@@H](OC(=O)\C=C\c1cc(O)c(O)cc1)C(=O)O | SMILES1 = C1=CC(=C(C=C1/C=C/C(=O)O[C@H]([C@H](C(=O)O)O)C(=O)O)O)O }} |Section2={{Chembox Properties | C=13 | H=12 | O=9 | BoilingPt = | Solubility = }} |Section3={{Chembox Hazards | MainHazards = | FlashPt = | AutoignitionPt = }} |Section4={{Chembox Related | OtherAnions = | OtherFunction_label = | OtherFunction = | OtherCompounds = }} }}

'''Caftaric acid''' is a non-flavonoid phenolic compound.

It is found in the juice of grapes<ref>{{cite journal |author1=C. Y. Lee |author2=A. Jaworski |year=1987 |title=Phenolic Compounds in White Grapes Grown in New York |journal=Am. J. Enol. Vitic. |volume=38 |issue=4 |pages=277–281 |doi=10.5344/ajev.1987.38.4.277 |s2cid=102310452 |url=http://ajevonline.org/content/38/4/277.short|url-access=subscription }}</ref><ref name="Understanding Wine Chemistry">{{cite book |last1=Waterhouse |first1=Andrew |last2=Sacks |first2=Gavin |last3=Jeffery |first3=David |title=Understanding Wine Chemistry |date=June 17, 2016 |publisher=Wiley Books |location=Adelaide |isbn=978-1-118-73072-0 |pages=112–113 |chapter=Chapter 13: Non‐flavonoid Phenolics}}</ref> (''Vitis vinifera'') and impacts the color of white wine.

It is an esterified phenolic acid, composed of caffeic acid, a hydroxycinnamate produced by plants, and tartaric acid, the principal organic acid found in grape berries. As such, caftaric acid is found in all grape juices and wines.<ref name="Understanding Wine Chemistry" /> During alcoholic and malolactic fermentation, the ester can be enzymatically hydrolysed, releasing the two constituents. Caffeic acid is susceptible to chemical oxidation, and subsequent redox reactions involving caffeic acid can contribute to wine browning over time, and the straw-gold color that can develop in some white wines after bottling.<ref name="Understanding Wine Chemistry" />

Aside from wine, it is abundantly present in raisins. It also occurs in ''Cichorium intybus'' (common chicory) and is one of the bioactive components of ''Echinacea purpurea'' (Eastern purple coneflower).<ref name=Vanzo>{{Cite journal |pmid=17300159| year=2007| last1=Vanzo |first1=A| last2=Cecotti |first2=R |last3=Vrhovsek |first3=U|last4=Torres |first4=AM|last5=Mattivi|first5=F| last6=Passamonti |first6=S |title=The fate of trans-caftaric acid administered into the rat stomach| volume=55 |issue=4| pages=1604–11| doi=10.1021/jf0626819|journal=Journal of Agricultural and Food Chemistry}}</ref>

Caftaric acid has a good bioavailability when fed in rats. Intact trans-caftaric acid was detected in rat plasma along with its O-methylated derivative trans-fertaric acid.<ref name=Vanzo/>

== In wine == Winemakers measure caftaric acid levels as their primary method to estimate the oxidation levels that a wine has undergone. For example, press wines, which undergo a high degree of oxidation{{Citation needed|date=December 2009}}, will have little to no caftaric acid.

Grape reaction product (2-S glutathionyl caftaric acid) is an oxidation compound produced from caftaric acid and found in wine. Malvidin 3-glucoside alone is not oxidized in the presence of grape polyphenol oxidase (PPO), whereas it is degraded in the presence of a crude grape PPO extract and of caftaric acid, forming anthocyanidin-caftaric acid adducts.<ref>{{Cite journal |last1=Sarni-Manchado |first1=Pascale |last2=Cheynier |first2=Véronique |last3=Moutounet |first3=Michel |date=August 1997 |title=Reactions of polyphenoloxidase generated caftaric acid o-quinone with malvidin 3-O-glucoside |url=https://linkinghub.elsevier.com/retrieve/pii/S0031942297001908 |journal=Phytochemistry |language=en |volume=45 |issue=7 |pages=1365–1369 |doi=10.1016/S0031-9422(97)00190-8|url-access=subscription }}</ref>

== See also == * Chicoric acid (dicaffeoyltartaric acid)

== References == {{Reflist}}

Category:Hydroxycinnamic acid esters Category:Catechols