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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] |
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 ... [...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] |
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 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioxidant
Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubricants, to prevent oxidation, and to foods to prevent spoilage, in particular the rancidification of oils and fats. In cells, antioxidants such as glutathione, mycothiol or bacillithiol, and enzyme systems like superoxide dismutase, can prevent damage from oxidative stress. The only dietary antioxidants are vitamins A, C, and E, but the term ''antioxidant'' has also been applied to numerous other dietary compounds that only have antioxidant properties in vitro, with little evidence for antioxidant properties in vivo. Dietary supplements marketed as antioxidants have not been shown to maintain health or prevent disease in humans. History As part of their adaptation from marine life, terrestrial plants began producing non-marine a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antidiabetic
Drugs used in diabetes treat diabetes mellitus by altering the glucose level in the blood. With the exceptions of insulin, most GLP receptor agonists ( liraglutide, exenatide, and others), and pramlintide, all are administered orally and are thus also called oral hypoglycemic agents or oral antihyperglycemic agents. There are different classes of anti-diabetic drugs, and their selection depends on the nature of the diabetes, age and situation of the person, as well as other factors. Diabetes mellitus type 1 is a disease caused by the lack of insulin. Insulin must be used in type 1, which must be injected. Diabetes mellitus type 2 is a disease of insulin resistance by cells. Type 2 diabetes mellitus is the most common type of diabetes. Treatments include agents that (1) increase the amount of insulin secreted by the pancreas, (2) increase the sensitivity of target organs to insulin, (3) decrease the rate at which glucose is absorbed from the gastrointestinal tract, and (4) in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticarcinogenic
An anticarcinogen (also known as a carcinopreventive agent) is a substance that counteracts the effects of a carcinogen or inhibits the development of cancer. Anticarcinogens are different from anticarcinoma agents (also known as anticancer or anti-neoplastic agents) in that anticarcinoma agents are used to selectively destroy or inhibit cancer cells ''after'' cancer has developed. Interest in anticarcinogens is motivated primarily by the principle that it is preferable to prevent disease (preventive medicine) than to have to treat it ( rescue medicine). In theory, anticarcinogens may act via different mechanisms including enhancement of natural defences against cancer, deactivation of carcinogens, and blocking the mechanisms by which carcinogens act (such as free radical damage to DNA). Confirmation that a substance possesses anticarcinogenic activity requires extensive ''in vitro'', ''in vivo'', and clinical investigation. Health claims for anticarcinogens are regulated by v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-inflammatory
Anti-inflammatory is the property of a substance or treatment that reduces inflammation or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs remedy pain by reducing inflammation as opposed to opioids, which affect the central nervous system to block pain signaling to the brain. Nonsteroidal anti-inflammatory drugs Nonsteroidal anti-inflammatory drugs (NSAIDs) alleviate pain by counteracting the cyclooxygenase (COX) enzyme. On its own, COX enzyme synthesizes prostaglandins, creating inflammation. In whole, the NSAIDs prevent the prostaglandins from ever being synthesized, reducing or eliminating the inflammation and resulting pain. Some common examples of NSAIDs are aspirin, ibuprofen, and naproxen. The newer specific COX-inhibitors are not classified together with the traditional NSAIDs, even though they presumably share the same mode of action. On the other hand, there are analgesics that are commonly associated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimicrobial
An antimicrobial is an agent that kills microorganisms or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals are used against fungi. They can also be classified according to their function. Agents that kill microbes are microbicides, while those that merely inhibit their growth are called bacteriostatic agents. The use of antimicrobial medicines to treat infection is known as antimicrobial chemotherapy, while the use of antimicrobial medicines to prevent infection is known as antimicrobial prophylaxis. The main classes of antimicrobial agents are disinfectants (non-selective agents, such as bleach), which kill a wide range of microbes on non-living surfaces to prevent the spread of illness, antiseptics (which are applied to living tissue and help reduce infection during surgery), and antibiotics (which destroy microorganisms within the body). The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2,3,4,6-pentagalloyl-β-d-glucose Galloyltransferase
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 Portag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydrogenation
In chemistry, dehydrogenation is a chemical reaction that involves the removal of hydrogen, usually from an organic molecule. It is the reverse of hydrogenation. Dehydrogenation is important, both as a useful reaction and a serious problem. At its simplest, it is useful way of converting alkanes, which are relatively inert and thus low-valued, to olefins, which are reactive and thus more valuable. Alkenes are precursors to aldehydes (), alcohols (), polymers, and aromatics. As a problematic reaction, the fouling and inactivation of many catalysts arises via coking, which is the dehydrogenative polymerization of organic substrates. Enzymes that catalyze dehydrogenation are called dehydrogenases. Heterogeneous catalytic routes Styrene Dehydrogenation processes are used extensively to produce aromatics in the petrochemical industry. Such processes are highly endothermic and require temperatures of 500 °C and above. Dehydrogenation also converts saturated fats to uns ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Compound from Geum japonicum and Syzygium aromaticum. Masahiko Kurokawa, Toyoharu Hozumi, Purusotam Basnet, Michio Nakano, Shigetoshi Kadota, Tuneo Namba, Takashi Kawana and Kimiyasu Shiraki, JPET, February 1, 1998 vol. 284 no. 2, pages 728-735article Tellimagrandin II is an isomer of punicafolin or nupharin A, but the hexahydroxydiphenoyl group is not attached to the same hydroxyl groups in the glucose molecule. The compound shows anti-herpesvirus properties. Metabolism It is formed by oxidation of pentagalloyl glucose in ''Tellima grandiflora'' by the enzyme pentagalloylglucose: O(2) oxidoreductase, a laccase-type phenol oxidase. It is further oxidized to casuarictin, a molecule formed via oxidative dehydrogenation of 2 other galloy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
