ellagitannin
{{short description|Diverse class of hydrolyzable tannins, a type of polyphenol}}
image:Castalagin.svg 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.{{cite journal |doi=10.1016/j.foodres.2011.04.027 |title=Ellagitannins, ellagic acid and their derived metabolites: A review about source, metabolism, functions and health |date=2011 |last1=Landete |first1=J.M. |journal=Food Research International |volume=44 |issue=5 |pages=1150–1160 }}
Ellagitannins contain various numbers of hexahydroxydiphenoyl units, as well as galloyl units and/or 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 intact.Structural diversity and antimicrobial activities of ellagitannins. T. Yoshida, Ts. Hatano, H. Ito, T. Okuda, S. Quideau (Ed.), Chemistry and Biology of Ellagitannins, World Scientific Publishing, Singapore (2009), pages 55–93
Ellagitannins generally form macrocycles, whereas gallotannins do not.
Examples
- Castalagin
- Castalin
- Casuarictin
- Grandinin
- Oenothein B from Willowherbs (Epilobium spp.)
- Roburin A
- Tellimagrandin II
- Terflavin B
- Vescalagin
- Pomegranate ellagitannins, many compounds
- Punicalagin
- Punicalin
Metabolism
= Degradation =
Urolithins, such as urolithin A, are microflora human metabolites of dietary ellagic acid derivatives.{{Cite journal |last1=Davis |first1=CD |last2=Milner |first2=JA |date=Oct 2009 |title=Gastrointestinal microflora, food components and colon cancer prevention |journal=J Nutr Biochem |volume=20 |issue=10 |pages=743–52 |doi=10.1016/j.jnutbio.2009.06.001 |pmc=2743755 |pmid=19716282}}
Natural occurrences
Ellagitannins are reported in dicotyledoneous angiospermes, and notably in species in the order Myrtales, such as the pomegranate.{{Cite journal |last=Yoshida |first=Takashi |year=2010 |title=Structural Features and Biological Properties of Ellagitannins in Some Plant Families of the Order Myrtales |journal=International Journal of Molecular Sciences |volume=11 |issue=1 |pages=79–106 |doi=10.3390/ijms11010079 |pmc=2820991 |pmid=20162003|doi-access=free }}{{Cite journal |last1=Gómez-Caravaca |first1=A. M. |last2=Verardo |first2=V |last3=Toselli |first3=M |last4=Segura-Carretero |first4=A |last5=Fernández-Gutiérrez |first5=A |last6=Caboni |first6=M. F. |year=2013 |title=Determination of the major phenolic compounds in pomegranate juices by HPLC−DAD−ESI-MS |journal=Journal of Agricultural and Food Chemistry |volume=61 |issue=22 |pages=5328–37 |doi=10.1021/jf400684n |pmid=23656584}}
See also
Other links
- [http://taninos.tripod.com/hidrolisables.htm MALDI-TOF Mass Spectrometric Analysis of Hydrolysable Tannins]
References
{{reflist}}
Further reading
- Quideau, Stéphane (editor). Chemistry and Biology of Ellagitannins: An Underestimated Class of Bioactive Plant Polyphenols, 2009, World Scientific Publishing. [https://web.archive.org/web/20220609075457/http://www.worldscibooks.com/etextbook/6795/6795_toc.pdf Table of Contents]. [https://web.archive.org/web/20220609075336/http://www.worldscibooks.com/etextbook/6795/6795_preface.pdf Preface]. [https://web.archive.org/web/20120417091220/http://www.worldscibooks.com/etextbook/6795/6795_chap01.pdf Chapter 1].
External links
- [http://www.users.muohio.edu/hagermae Tannin Chemistry] (Tannin Handbook, Copyright 1998, 2002, 2011, Ann E. Hagerman)
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{{Ellagitannin}}