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Gallotannins
A gallotannin is any of a class of molecules belonging to the hydrolysable tannins. Gallotannins are polymers formed when gallic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose. Metabolism Gallate 1-beta-glucosyltransferase uses UDP-glucose and gallate to produce UDP and 1-galloyl-beta-D-glucose. Beta-glucogallin O-galloyltransferase uses 1-O-galloyl-beta-D-glucose to produce D-glucose and 1-O,6-O-digalloyl-beta-D-glucose. Beta-glucogallin-tetrakisgalloylglucose O-galloyltransferase uses 1-O-galloyl-beta-D-glucose and 1,2,3,6-tetrakis-O-galloyl-beta-D-glucose to produce D-glucose and 1,2,3,4,6-pentakis-O-galloyl-beta-D-glucose (1,2,3,4,6-penta-O-galloyl-β-D-glucose, the common precursor of gallotannins and the related ellagitannins). Tannase is a key enzyme in the degradation of gallotannins that uses digallic acid and H2O to produce gallic acid. See also * List of antioxidants in food This is a list of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-O-galloyl-beta-D-glucose
Glucogallin is chemical compound formed from gallic acid and β-D-glucose. It can be found in oaks species like the North American white oak (''Quercus alba''), European red oak (''Quercus robur'') and Amla fruit (''Phyllanthus emblica''). It is formed by a gallate 1-beta-glucosyltransferase (UDP-glucose: gallate glucosyltransferase), an enzyme performing the esterification of two substrates, UDP-glucose and gallate to yield two products, UDP and glucogallin. This enzyme can be found in oak leaf preparations. This the first step in the biosynthesis of gallotannins. The molecule is then used by enzymes in the gallotannins synthetics pathway like beta-glucogallin O-galloyltransferase or beta-glucogallin-tetrakisgalloylglucose O-galloyltransferase. β-Glucogallin is aldose reductase inhibitor Aldose reductase inhibitors are a class of drugs being studied as a way to prevent eye and nerve damage in people with diabetes. Mechanism Their target, aldose reductase, is an enzyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-O,6-O-digalloyl-beta-D-glucose
1-''O'',6-''O''-Digalloyl-β-D-glucose is a gallotannin A gallotannin is any of a class of molecules belonging to the hydrolysable tannins. Gallotannins are polymers formed when gallic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose. Meta .... It can be found in some oak species. References Gallotannins {{phenol-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digallic Acid
Digallic acid is a polyphenolic compound found in '' Pistacia lentiscus''. Digallic acid is also present in the molecule of tannic acid. Digalloyl esters involve either ''-meta'' or ''-para'' depside bonds. Tannase is an enzyme that uses digallate to produce gallic acid. This enzyme can also be used to produce digallic acid from gallotannin A gallotannin is any of a class of molecules belonging to the hydrolysable tannins. Gallotannins are polymers formed when gallic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose. Meta ...s. References Gallotannins Trihydroxybenzoic acids Pyrogallols Benzoate esters Vinylogous carboxylic acids {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2,3,4,6-pentagalloyl-glucose
1,2,3,4,6-Pentagalloylglucose is the pentagallic acid ester of glucose. It is a gallotannin and the precursor of ellagitannins. Pentagalloyl glucose can precipitate proteins, including human salivary α-amylase. Natural occurrence 1,2,3,4,6-Pentagalloyl glucose can be found in ''Punica granatum'' (pomegranate), '' Elaeocarpus sylvestris'', ''Rhus typhina'' (Staghorn sumac), ''Paeonia suffruticosa'' (Tree Peony),., ''Mangifera indica'' (mango) and ''Bouea macrophylla'' Griffith ( maprang). Biosynthesis The enzyme beta-glucogallin-tetrakisgalloylglucose O-galloyltransferase uses 1-O-galloyl-beta-D-glucose and 1,2,3,6-tetrakis-O-galloyl-beta-D-glucose to produce D-glucose and pentagalloyl glucose. Metabolism Tellimagrandin II is formed from pentagalloyl glucose by oxidative dehydrogenation and coupling of 2 galloyl groups. β-glucogallin: 1,2,3,4,6-pentagalloyl-β-d-glucose galloyltransferase is an enzyme found in the leaves of ''Rhus typhina'' that catalyzes the galloy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-galloyl-beta-D-glucose
Glucogallin is chemical compound formed from gallic acid and β-D-glucose. It can be found in oaks species like the North American white oak (''Quercus alba''), European red oak (''Quercus robur'') and Amla fruit (''Phyllanthus emblica''). It is formed by a gallate 1-beta-glucosyltransferase (UDP-glucose: gallate glucosyltransferase), an enzyme performing the esterification of two substrates, UDP-glucose and gallate to yield two products, UDP and glucogallin. This enzyme can be found in oak leaf preparations. This the first step in the biosynthesis of gallotannins. The molecule is then used by enzymes in the gallotannins synthetics pathway like beta-glucogallin O-galloyltransferase or beta-glucogallin-tetrakisgalloylglucose O-galloyltransferase. β-Glucogallin is aldose reductase inhibitor Aldose reductase inhibitors are a class of drugs being studied as a way to prevent eye and nerve damage in people with diabetes. Mechanism Their target, aldose reductase, is an enzyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallic Acid
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 is a white solid, although samples are typically brown owing to partial oxidation. Salts and esters of gallic acid are termed "gallates". Isolation and derivatives Gallic acid is easily freed from gallotannins by acidic or alkaline hydrolysis. When heated with concentrated sulfuric acid, gallic acid converts to rufigallol. Hydrolyzable tannins break down on hydrolysis to give gallic acid and glucose or ellagic acid and glucose, known as gallotannins and ellagitannins, respectively. Biosynthesis Gallic acid is formed from 3-dehydroshikimate by the action of the enzyme shikimate dehydrogenase to produce 3,5-didehydroshikimate. This latter compound aromatizes. Reactions Oxidation and oxidative coupling Alkaline solutions of gallic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tannase
The enzyme tannase (EC 3.1.1.20) catalyzes the following reaction: :digallate + H2O = 2 gallate It is a key enzyme in the degradation of gallotannins and ellagicitannins, two types of hydrolysable tannins. Specifically, tannase catalyzes the hydrolysis of ester and depside bonds of hydrolysable tannins to release glucose and gallic or ellagic acid. Tannase belongs to the family of hydrolases, specifically those acting on carboxylic ester bonds. The systematic name is tannin acylhydrolase. Other names in common use include tannase S, and tannin acetylhydrolase. This enzyme has two known domains and one known active site. Tannase can be found in plants, bacteria, and fungi and has different purposes depending on the organism it is found in. Tannase also has many purposes for human use. The production of gallic acid is important in the pharmaceutical industry as it's needed to create trimethoprim, an antibacterial drug. Tannase also has many applications in the food and beverage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2,3,6-tetrakis-O-galloyl-beta-D-glucose
Onekama ( ) is a village in Manistee County in the U.S. state of Michigan. The population was 411 at the 2010 census. The village is located on the shores of Portage Lake and is surrounded by Onekama Township. The town's name is derived from "Ona-ga-maa," an Anishinaabe word which means "singing water." Geography According to the United States Census Bureau, the village has a total area of , all land. The M-22 highway runs through downtown Onekama. History The predecessor of the village of Onekama was the settlement of Portage at Portage Point, first established in 1845, at the western end of Portage, at the outlet of Portage Creek. In 1871, when landowners around the land-locked lake became exasperated with the practices of the Portage Sawmill, they took the solution into their own hands and dug a channel through the narrow isthmus, opening a waterway that lowered the lake by 12 to 14 feet and brought it to the same level as Lake Michigan. When this action dried out Portage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysable Tannin
A hydrolyzable tannin or pyrogallol-type tannin is a type of tannin that, on heating with hydrochloric or sulfuric acids, yields gallic or ellagic acids. At the center of a hydrolyzable tannin molecule, there is a carbohydrate (usually D-glucose but also cyclitols like quinic or shikimic acids). The hydroxyl groups of the carbohydrate are partially or totally esterified with phenolic groups such as gallic acid in gallotannins or ellagic acid in ellagitannins. Hydrolysable tannins are mixtures of polygalloyl glucoses and/or poly-galloyl quinic acid derivatives containing in between 3 up to 12 gallic acid residues per molecule. Hydrolyzable tannins are hydrolyzed by weak acids or weak bases to produce carbohydrate and phenolic acids. Examples of gallotannins are the gallic acid esters of glucose in tannic acid (C76H52O46), found in the leaves and bark of many plant species. Hydrolysable tannins can be extracted from different vegetable plants, such as chestnut wood (''Castanea s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
D-glucose
Glucose is a simple sugar with the Chemical formula#Molecular formula, 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 energy from sunlight, where it is used to make cellulose in cell walls, the most abundant carbohydrate in the world. In energy metabolism, glucose is the most important source of energy in all organisms. Glucose for metabolism is stored as a polymer, in plants mainly as starch and amylopectin, and in animals as glycogen. Glucose circulates in the blood of animals as blood sugar. The naturally occurring form of glucose is -glucose, while L-glucose, -glucose is produced synthetically in comparatively small amounts and is less biologically active. Glucose is a monosaccharide containing six carbon atoms and an Aldehyde , aldehyde group, and is therefore an aldohexose. The glucose molecule can exist in an op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta-glucogallin O-galloyltransferase
In enzymology, a beta-glucogallin O-galloyltransferase () is an enzyme that catalyzes the chemical reaction :2 1-O-galloyl-beta-D-glucose \rightleftharpoons D-glucose + 1-O,6-O-digalloyl-beta-D-glucose Hence, this enzyme has one substrate, 1-O-galloyl-beta-D-glucose, and two products, D-glucose and 1-O,6-O-digalloyl-beta-D-glucose. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is 1-O-galloyl-beta-D-glucose:1-O-galloyl-beta-D-glucose O-galloyltransferase. References * * EC 2.3.1 Enzymes of unknown structure {{2.3-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
