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Ellagitannins
image:Castalagin.svg, 130px, Castalagin is a representative ellagitannin, characterized by coupled gallic acid substituents The ellagitannins are a diverse class of hydrolyzable tannins, a type of polyphenol formed primarily from the oxidative linkage of galloyl groups in 1,2,3,4,6-pentagalloyl glucose. Ellagitannins differ from gallotannins, in that their galloyl groups are linked through C-C bonds, whereas the galloyl groups in gallotannins are linked by depside bonds. Ellagitannins contain various numbers of Hexahydroxydiphenic acid, hexahydroxydiphenoyl units, as well as galloyl units and/or Sanguisorbic acid, sanguisorboyl units bounded to sugar moiety. In order to determine the quantity of every individual unit, the hydrolysis of the extracts with trifluoroacetic acid in methanol/water system is performed. Hexahydroxydiphenic acid, created after hydrolysis, spontaneously lactonized to ellagic acid, and sanguisorbic acid to sanguisorbic acid dilactone, while gallic acid remains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Castalagin
Castalagin is an ellagitannin, a type of hydrolyzable tannin, found in oak and chestnut wood and in the stem barks of ''Terminalia leiocarpa'' and ''Terminalia avicennoides''. Castalagin is the diastereomer of vescalagin in C-1 of the glycosidic chain. Castalagin/ vescalagin are the most abundant ellagitannins in white wine stored in Oak (wine), oak barrels. During Aging of wine, aging of wines, these two compounds were progressively extracted from the wood and were transformed into new derivatives by chemical reactions. Therefore, castalagin/ vescalagin and their derivatives contribute to the color and the taste of wines and spirits stored in oak barrels. Sources Castalagin was first isolated in Fagaceae family woody species : Oak, ''Quercus'' (oak) and ''Chestnut, Castanea'' (chestnut) by Walter Mayer and co-workers (1967). In some chestnut species, such as ''Castanea sativa'', heartwood could contain 63 mg of castalagin/ vescalagin per gram of dry wood. In some Wine, wines, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Ellagic Acid
Ellagic acid is a polyphenol found in numerous fruits and vegetables. It is the dilactone of hexahydroxydiphenic acid. Name The name comes from the French term ''acide ellagique'', from the word ''galle'' spelled backward because it can be obtained from ''noix de galle'' (galls), and to distinguish it from ''acide gallique'' ( gallic acid). The molecular structure resembles to that of two gallic acid molecules being assembled "head to tail" and bound together by a C–C bond (as in biphenyl, or in diphenic acid) and two lactone links (cyclic carboxylic esters). Metabolism Biosynthesis Plants produce ellagic acid from hydrolysis of tannins such as ellagitannin and geraniin. Biodegradation Urolithins are gut flora human metabolites of dietary ellagic acid derivatives. Ellagic acid has low bioavailability, with 90% remaining unabsorbed from the intestines until metabolized by microflora to the more bioavailable urolithins. History Ellagic acid was first discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Urolithin A
Urolithin A is a metabolite compound resulting from the transformation of ellagitannins by the gut bacteria. It belongs to the class of organic compounds known as benzo-coumarins or dibenzo-α-pyrones. Its precursors – ellagic acids and ellagitannins – are ubiquitous in nature, including edible plants, such as pomegranates, Strawberry, strawberries, Raspberry, raspberries, walnuts, and others. Urolithin A is not known to be found in any food source. Its bioavailability mostly depends on individual microbiota composition, as only some bacteria are able to convert ellagitannins into urolithins. Chemistry Urolithin A belongs to the class of organic compounds known as benzo-coumarins or dibenzo-α-pyrones. These are polycyclic compound, polycyclic aromatic compounds containing a 1-benzopyran moiety with a ketone group at the C2 carbon atom (1-benzopyran-2-one). Biochemistry and metabolism Pomegranate fruits, walnuts, and Raspberry, raspberries are sources of ellagitannins. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Pomegranate Ellagitannin
The pomegranate ellagitannins, which include punicalagin isomers, are ellagitannins found in the sarcotestas, rind (peel), bark or heartwood of the pomegranate fruit (''Punica granatum''). Chemistry As the chemistry of punicalagins became known it was found to be not unique to pomegranate. Punicalagins are present in numerous species of the genus ''Terminalia (plant), Terminalia'', species ''Terminalia chebula, chebula'' Retz. ("Fructus Chebulae"), ''Terminalia myriocarpa, myriocarpa'', ''Terminalia catappa, catappa'' and Terminalia citrina, citrina (tropical flowering trees historically used in African traditional medicine for antibiotic and antifungal purposes). They have also been isolated from ''Cistus salvifolius'' (a Mediterranean shrub) and ''Combretum molle'' (an African shrub). Pomegranate fruits natural phenols can be extracted with ethyl acetate and fractionation can afford the ellagitannin punicalagins. Dietary supplementation A few dietary supplements and nutrit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |