Castalagin is an

ellagitannin 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 group ...

, a type of hydrolyzable tannin, found in

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

and

chestnut The chestnuts are the deciduous trees and shrubs in the genus ''Castanea'', in the beech family Fagaceae. They are native to temperate regions of the Northern Hemisphere. The name also refers to the edible nuts they produce. The unrelat ...

wood and in the stem barks of ''

Anogeissus leiocarpus ''Anogeissus leiocarpa'' (African birch; bm, ngálǎma) is a tall deciduous tree native to the savannas of tropical Africa. It is the sole West African species of the genus ''Anogeissus'', a genus otherwise distributed from tropical central a ...

'' and ''

Terminalia avicennoides ''Terminalia avicennioides'' ( bm, Wolobugun) is a tree species in the genus '' Terminalia'' found in West Africa. Castalagin and flavogallonic acid dilactoneThe use of microfluorometric method for activity-guided isolation of antiplasmodial co ...

''. Castalagin is the

diastereomer In stereochemistry, diastereomers (sometimes called diastereoisomers) are a type of stereoisomer. Diastereomers are defined as non-mirror image, non-identical stereoisomers. Hence, they occur when two or more stereoisomers of a compound have dif ...

of vescalagin in C-1 of the glycosidic chain. Castalagin/ vescalagin are the most abundant ellagitannins in white wine stored in

oak barrels Oak is used in winemaking to vary the color, flavor, tannin profile and texture of wine. It can be introduced in the form of a barrel during the fermentation or aging periods, or as free-floating chips or staves added to wine fermented in a v ...

. During 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 The Fagaceae are a family of flowering plants that includes beeches, chestnuts and oaks, and comprises eight genera with about 927 species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species occur as evergre ...

family woody species : ''Quercus'' (oak) and '' Castanea'' (chestnut) by Walter Mayer and co-workers (1967). In some chestnut species, such as ''

Castanea sativa ''Castanea sativa'', the sweet chestnut, Spanish chestnut or just chestnut, is a species of tree in the family Fagaceae, native to Southern Europe and Asia Minor, and widely cultivated throughout the temperate world. A substantial, long-lived ...

'', heartwood could contain 63 mg of castalagin/ vescalagin per gram of dry wood. In some

wines Wine is an alcoholic drink typically made from fermented grapes. Yeast consumes the sugar in the grapes and converts it to ethanol and carbon dioxide, releasing heat in the process. Different varieties of grapes and strains of yeasts are m ...

, these two isomers represent about 40 to 70% of total ellagitannins.

Biosynthesis

In some plants including oak and chestnut, the ellagitannins are formed from 1,2,3,4,6-pentagalloyl-glucose and further elaborated via oxidative dehydrogenation (

tellimagrandin II Tellimagrandin II is the first of the ellagitannins formed from 1,2,3,4,6-pentagalloyl-glucose. It can be found in '' Geum japonicum'' and ''Syzygium aromaticum'' (clove).Purification and Characterization of Eugeniin as an Anti-herpesvirus Compoun ...

and

casuarictin Casuarictin is an ellagitannin, a type of hydrolysable tannin. It can be found in ''Casuarina'' and ''Stachyurus'' species.Tannins of Casuarina and Stachyurus species. I: Structures of pendunculagin, casuarictin, strictinin, casuarinin, casuariin, ...

formations). After conversion of

pedunculagin Pedunculagin is an ellagitannin. It is formed from casuarictin via the loss of a gallate group. Natural occurrence Pedunculagin is found in plants in orders in the clade Rosidae. It can be found the pericarp of pomegranates (''Punica granatum' ...

, the pyranose ring of the

glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using ...

opens and the family of compounds including casuariin,

casuarinin Casuarinin is an ellagitannin. It is found in the pericarp of pomegranates (''Punica granatum''). It is also found in ''Casuarina'' and '' Stachyurus'' species and in '' Alnus sieboldiana''. It is an isomer of casuarictin. It is a highly active ...

, castalagin, and

castlin Castalin is an ellagitannin. It can be found in oak wood and in ''Melaleuca quinquenervia ''Melaleuca quinquenervia'', commonly known as the broad-leaved paperbark, paper bark tea tree, punk tree or niaouli, is a small- to medium-sized tree o ...

, vescalagin and vescalin forms. Castalagin thus forms from a penta

galloyl Gallic acid (also known as 3,4,5-trihydroxybenzoic acid) is a trihydroxybenzoic acid with the formula C6 H2( OH)3CO2H. It is classified as a phenolic acid. It is found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. It ...

-glucose structure. Castalagin and vescalagin (1,2,3,5- nonahydroxytriphenoyl-4,6-

hexahydroxydiphenoyl Hexahydroxydiphenic acid is an organic compound with the formula HO)3C6HCO2Hsub>2. It is the oxidatively coupled derivative of gallic acid It is a white solid, although samples are typically brown owing to oxidation. left, 142px, Ellagic acid. ...

-glucoses) can be further polymerized in their corresponding

dimer Dimer may refer to: * Dimer (chemistry), a chemical structure formed from two similar sub-units ** Protein dimer, a protein quaternary structure ** d-dimer * Dimer model, an item in statistical mechanics, based on ''domino tiling'' * Julius Dimer ...

roburin A Roburin A is a tannin found in oak wood (''Quercus robur'' and ''Quercus petraea'' or ''Quercus alba'') or oak cork (''Quercus suber''). It is a dimeric compound, composed of two vescalagin Castalagin is an ellagitannin, a type of hydrolyzable ta ...

and roburin D, and 33-carboxy-33-deoxyvescalagin.

Derivatives

Castalagin and other related ellagitanins polymerizes or forms complexes with anthyocyanins and

flavonoids Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans. Chemically, flavonoids ...

. The flavono-ellagitannin known as acutissimin A is created when the oak tannin vescalagin interacts with

catechin Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids. The name of the catechin chemical family derives from ''catechu'', which is the tannic ...

flavan-3-ol Flavan-3-ols (sometimes referred to as flavanols) are a subgroup of flavonoids. They are derivatives of flavans that possess a 2-phenyl-3,4-dihydro-2''H''-chromen-3-ol skeleton. Flavan-3-ols are structurally diverse and include a range of compo ...

found in wine.

Grandinin Grandinin is an ellagitannin. It can be found in ''Melaleuca quinquenervia'' leavesPolyphenols of Melaleuca quinquenervia leaves - pharmacological studies of grandinin. Moharram F. A., Marzouk M. S., El-Toumy S. A. A., Ahmed A. A. E. and Aboutabl ...

is a castalagin glycoside which forms by binding to the pentose

lyxose Lyxose is an aldopentose — a monosaccharide containing five carbon atoms, and including an aldehyde functional group. It has chemical formula . It is a C'-2 carbon epimer of the sugar xylose. The name "lyxose" comes from reversing the prefix "xyl ...

. Chemical hydrolysis of Castalagin/ Vescalagin produces vescalene and vescalin which are potent

topoisomerase II Type II topoisomerases are topoisomerases that cut both strands of the DNA helix simultaneously in order to manage DNA tangles and supercoils. They use the hydrolysis of ATP, unlike Type I topoisomerase. In this process, these enzymes change the ...

inhibitors.

References

{{Ellagitannin Ellagitannins