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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 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 c ... subunits probably linked through an ether bond between the diphenoyl group ( hexahydroxydiphenic acid or HHDP) of one subunit and the triphenoyl moiety ( nonahydroxytriphenic acid) of the other one. References Ellagitannins Tannin dimers {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Robur
''Quercus robur'', the pedunculate oak, is a species of flowering plant in the beech and oak family, Fagaceae. It is a large tree, native plant, native to most of Europe and western Asia, and is widely cultivated in other temperate regions. It grows on soils of near neutral Soil pH, acidity in the lowlands and is notable for its value to natural ecosystems, supporting a very wide diversity of herbivorous insects and other pests, predators and pathogens. Description Pedunculate oak is a deciduous tree up to tall, with a single stout trunk that can be as much as in girth (circumference at breast height) or even 14 m in Pollarding, pollarded specimens. Older trees tend to be pollarded, with boles (the main trunk) about 3 m long. They often live longer and become more stout than unpollarded trees. The crown is spreading and unevenly domed, and trees often have massive lower branches. The bark is greyish-brown and closely grooved, with vertical plates. There are often large burrs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Petraea
''Quercus petraea'', commonly known as the sessile oak, Welsh oak, Cornish oak, Irish oak or durmast oak, is a species of oak tree native to most of Europe and into Anatolia and Iran. The sessile oak is the national tree of Ireland, and an unofficial emblem in Wales and Cornwall. Description The sessile oak is a large deciduous tree up to tall, in the white oak section of the genus (''Quercus'' sect. ''Quercus'') and similar to the pedunculate oak (''Q. robur''), with which it overlaps extensively in range. The leaves are long and broad, evenly lobed with five to six lobes on each side and a petiole. The male flowers are grouped into catkins, produced in the spring. The fruit is an acorn long and broad, which matures in about six months. File:Divljanski stari hrast.jpg, Old sacred oak ( zapis) in Divljana, Serbia File:Quercus petraea 02.jpg, Shoot with leaves and acorn File:Eglinton fish pond island inosculated Q. petraea.JPG, An inosculated tree File:Sessile O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Alba
''Quercus alba'', the white oak, is one of the preeminent hardwoods of eastern and central North America. It is a long-lived oak, native to eastern and central North America and found from Minnesota, Ontario, Quebec, and southern Maine south as far as northern Florida and eastern Texas. Specimens have been documented to be over 450 years old. Although called a white oak, it is very unusual to find an individual specimen with white bark; the usual colour is a light gray. The name comes from the colour of the finished wood. In the forest it can reach a magnificent height and in the open it develops into a massive broad-topped tree with large branches striking out at wide angles. Description ''Quercus alba'' typically reaches heights of at maturity, and its canopy can become quite massive as its lower branches are apt to extend far out laterally, parallel to the ground. Trees growing in a forest will become much taller than ones in an open area which develop to be short and mass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Suber
''Quercus suber'', commonly called the cork oak, is a medium-sized, evergreen oak tree in the section ''Quercus'' sect. ''Cerris''. It is the primary source of cork for wine bottle stoppers and other uses, such as cork flooring and as the cores of cricket balls. It is native to southwest Europe and northwest Africa. In the Mediterranean basin the tree is an ancient species with fossil remnants dating back to the Tertiary period. It can survive for as long as two centuries. Typically, once it reaches 25 years old, its thick bark can be harvested for cork every 9 to 12 years without causing harm to the tree. It endures drought and makes little demand on the soil quality and is regarded as a defence against desertification. Cork oak woodlands are home to a multitude of animal and plant species. Since cork for sealing bottles is increasingly being displaced by other materials, these forests are at risk as part of the cultural landscape and as a result animal species such as the I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vescalagin
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] |
Hexahydroxydiphenic Acid
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. Occurrence left, 142px, Ellagic acid. Luteic acid and ellagic acid are the mono- and di lactone of hexahydroxydiphenic acid, respectively. Hexahydroxydiphenic acid is a component of some ellagitannin 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 link ...s, such as casuarictin. See also * Diphenic acid References Ellagitannins Pyrogallols Biphenyls Trihydroxybenzoic acids {{phenol-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonahydroxytriphenic Acid
Nonahydroxytriphenic acid is a moiety found in some ellagitannins such as roburin A, B,C and D, 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 c ... or grandinin.Roburin A, a dimeric ellagitannin from heartwood of Quercus robur. Hervé Du Penhoat, Michon V. M. F., Ohassan A., Shuyun Peng, Scalbert A. and Gage D., Phytochemistry, 1991, vol. 30, no 1, pages 329-332, References Ellagitannins Tricarboxylic acids {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
