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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. 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 Gallic acid (also known as 3,4,5-trihydroxybenzoic acid) is ... [...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 gallo ... [...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 t ... [...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 t ... [...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 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 .... This enzyme can also be used to produce digallic acid from gallotannins. References Gallotannins Trihydroxybenzoic acids Pyrogallols Benzoate esters Vinylogous carboxylic acids {{aromatic-stub ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Antioxidants In Food
This is a list of antioxidants naturally occurring in food. Vitamin C and vitamin E – which are ubiquitous among raw plant foods – are confirmed as dietary antioxidants, whereas vitamin A becomes an antioxidant following metabolism of provitamin A beta-carotene and cryptoxanthin. Most food compounds listed as antioxidants – such as polyphenols common in colorful, edible plants – have antioxidant activity only in vitro, as their fate in vivo is to be rapidly metabolized and excreted, and the in vivo properties of their metabolites remain poorly understood. For antioxidants added to food to preserve them, see butylated hydroxyanisole and butylated hydroxytoluene. Regulatory guidance In the following discussion, the term "antioxidant" refers mainly to non-nutrient compounds in foods, such as polyphenols, which have ''antioxidant capacity'' in vitro and so provide an artificial index of antioxidant strength – the ORAC measurement. Other than for dietary ... [...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] |
Uridine Diphosphate
Uridine diphosphate, abbreviated UDP, is a nucleotide diphosphate. It is an ester of pyrophosphoric acid with the nucleoside uridine. UDP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase uracil. UDP is an important factor in glycogenesis. Before glucose can be stored as glycogen in the liver and muscles, the enzyme UDP-glucose pyrophosphorylase forms a UDP-glucose unit by combining glucose 1-phosphate with uridine triphosphate, cleaving a pyrophosphate ion in the process. Then, the enzyme glycogen synthase combines UDP-glucose units to form a glycogen chain. The UDP molecule is cleaved from the glucose ring during this process and can be reused by UDP-glucose pyrophosphorylase. See also * DNA * Nucleoside * Nucleotide Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
D-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 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 -glucose is produced synthetically in comparatively small amounts and is less biologically active. Glucose is a monosaccharide containing six carbon atoms and an aldehyde group, and is therefore an aldohexose. The glucose molecule can exist in an open-chain (acyclic) as well as ring (cyclic) form. Gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UDP-glucose
Uridine diphosphate glucose (uracil-diphosphate glucose, UDP-glucose) is a nucleotide sugar. It is involved in glycosyltransferase reactions in metabolism. Functions UDP-glucose is used in nucleotide sugar metabolism as an activated form of glucose, a substrate for enzymes called glucosyltransferases. UDP-glucose is a precursor of glycogen and can be converted into UDP-galactose and UDP-glucuronic acid, which can then be used as substrates by the enzymes that make polysaccharides containing galactose and glucuronic acid. UDP-glucose can also be used as a precursor of sucrose, lipopolysaccharides and glycosphingolipids. Components UDP-glucose consists of the pyrophosphate group, ribose, glucose, and uracil. See also * DNA * Nucleoside * Nucleotide * Oligonucleotide * RNA * TDP-glucose * Uracil * Uridine diphosphate Uridine diphosphate, abbreviated UDP, is a nucleotide diphosphate. It is an ester of pyrophosphoric acid with the nucleoside uridine. UDP consists of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
