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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 is a white solid, although samples are typically brown owing to partial oxidation. Salts and esters of gallic acid are termed "gallates". Its name is derived from oak galls, which were historically used to prepare tannic acid. Despite the name, gallic acid does not contain gallium. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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-β-D-glucose. Beta-glucogallin O-galloyltransferase uses 1-O-galloyl-β-D-glucose to produce D-glucose and 1-O,6-O-digalloyl-β-D-glucose. Beta-glucogallin-tetrakisgalloylglucose O-galloyltransferase uses 1-O-galloyl-β-D-glucose and 1,2,3,6-tetrakis-O-galloyl-β-D-glucose to produce D-glucose and 1,2,3,4,6-pentakis-O-galloyl-β-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 antio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tannic Acid
Tannic acid is a specific form of tannin, a type of polyphenol. Its weak acidity (Acid dissociation constant, pKa around 6) is due to the numerous phenol groups in the structure. The chemical formula for commercial tannic acid is often given as C76H52O46, which corresponds with decagalloyl glucose, but in fact it is a mixture of polygalloyl glucoses or polygalloyl quinic acid esters with the number of gallic acid, galloyl moieties per molecule ranging from 2 up to 12 depending on the plant source used to extract the tannic acid. Commercial tannic acid is usually extracted from any of the following plant parts: Tara pods (''Caesalpinia spinosa''), gallnuts from ''Rhus semialata'' or ''Quercus infectoria'' or Sicilian sumac leaves (''Rhus coriaria''). According to the definitions provided in external references such as international pharmacopoeia, Food Chemicals Codex and FAO-WHO tannic acid monograph only tannins obtained from the above-mentioned plants can be considered as tanni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellagic Acid
Ellagic acid is a polyphenol found in numerous fruits and vegetables. It is the dilactone of hexahydroxydiphenic acid. Name The name comes from the French term ''acide ellagique'', from the word ''galle'' spelled backward because it can be obtained from ''noix de galle'' (galls), and to distinguish it from ''acide gallique'' ( gallic acid). The molecular structure resembles to that of two gallic acid molecules being assembled "head to tail" and bound together by a C–C bond (as in biphenyl, or in diphenic acid) and two lactone links (cyclic carboxylic esters). Metabolism Biosynthesis Plants produce ellagic acid from hydrolysis of tannins such as ellagitannin and geraniin. Biodegradation Urolithins are gut flora human metabolites of dietary ellagic acid derivatives. Ellagic acid has low bioavailability, with 90% remaining unabsorbed from the intestines until metabolized by microflora to the more bioavailable urolithins. History Ellagic acid was first discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the pseudoelement symbol for ethyl group, ethyl. Ethanol is a Volatility (chemistry), volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. As a psychoactive depressant, it is the active ingredient in alcoholic beverages, and the second most consumed drug globally behind caffeine. Ethanol is naturally produced by the fermentation process of sugars by yeasts or via petrochemical processes such as ethylene hydration. Historically it was used as a general anesthetic, and has modern medical applications as an antiseptic, disinfectant, solvent for some medications, and antidote for methanol poisoning and ethylene glycol poisoning. It is used as a chemical solvent and in the Chemical synthesis, synthesis of orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallnut
Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants. Plant galls are abnormal outgrowths of plant tissues, similar to benign tumors or warts in animals. They can be caused by various parasites, from viruses, fungi and bacteria, to other plants, insects and mites. Plant galls can be such highly organized structures that their cause can be determined without the actual agent being identified. This applies particularly to insect and mite plant galls. The study of plant galls is known as cecidology. Anatomy Shape and size Galls develop on various plant organs, providing nutrition and shelter to inducing insects. Galls display vast variation in morphology, size, and wall composition. The size of insect galls can range significantly, from approximately two inches in diameter to less than one-sixteenth of an inch. Some galls are so small that they are merely slightly thickened ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of Biomolecule, biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallic Acid ESP
Gallic is an adjective that may describe: * ancient Gaul (Latin: Gallia), roughly corresponding to the territory of modern France **pertaining to the Gauls **Roman Gaul (1st century BC to 5th century) **Gallic Empire (260–273) **Frankish Gaul (5th to 8th centuries) ** A Latinism for France, the French people, and their customs * Gallic epoch, an obsolete epoch of the Cretaceous * pertaining to gall, a formation induced by a parasite in plants, **hence the name gallic acid, for a phenolic compound found in these formations 'Gallic' is also a proper noun naming the following ships: * , a paddle wheel steamship * , a cargo steamship See also * Gaulish * Gallican * Galician (other) * Gaelic (other) * Gallium, a chemical element * Galik script, a variation of the traditional Mongolian script * Gallica (other) * Gallicism A Gallicism can be: * a mode of speech peculiar to the French; * a French idiom; * in general, a French mode or custom. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium
Gallium is a chemical element; it has Chemical symbol, symbol Ga and atomic number 31. Discovered by the French chemist Paul-Émile Lecoq de Boisbaudran in 1875, elemental gallium is a soft, silvery metal at standard temperature and pressure. In its liquid state, it becomes silvery white. If enough force is applied, solid gallium may fracture conchoidal fracture, conchoidally. Since its discovery in 1875, gallium has widely been used to make alloys with low melting points. It is also used in semiconductors, as a dopant in semiconductor substrates. The melting point of gallium, , is used as a temperature reference point. Gallium alloys are used in thermometers as a non-toxic and environmentally friendly alternative to Mercury (element), mercury, and can withstand higher temperatures than mercury. A melting point of , well below the freezing point of water, is claimed for the alloy galinstan (62–95% gallium, 5–22% indium, and 0–16% tin by weight), but that may be t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oak Gall
An oak apple or oak gall is a large, round, vaguely apple-like gall commonly found on many species of oak. Oak apples range in size from in diameter and are caused by chemicals injected by the larva of certain kinds of gall wasp in the family Cynipidae. Formation The adult female wasp lays single eggs in developing leaf buds. The wasp larvae feed on the gall tissue resulting from their secretions, which modify the oak bud into the gall, a structure that protects the developing larvae until they undergo metamorphosis into adults. Some common oak-apple-forming species are the '' Biorhiza pallida'' gall wasp in Europe, '' Amphibolips confluenta'' in eastern North America, and '' Atrusca bella'' in western North America. Oak apples may be brownish, yellowish, greenish, pinkish, or reddish. Other galls Considerable confusion exists in the general literature between the oak apple and the oak marble gall. The oak marble is frequently called the oak apple due to the superficial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distinctive functional group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well (e.g. amides), but not according to the IUPAC. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Lactones are cyclic carboxylic esters; naturally occurring lactones are mainly 5- and 6-membered ring lactones. Lactones contribute to the aroma of fruits, butter, cheese, vegetables like celery and other foods. Esters can be formed from oxoacids (e.g. esters of acetic acid, carbonic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt (chemistry)
In chemistry, a salt or ionic compound is a chemical compound consisting of an assembly of positively charged ions ( cations) and negatively charged ions ( anions), which results in a compound with no net electric charge (electrically neutral). The constituent ions are held together by electrostatic forces termed ionic bonds. The component ions in a salt can be either inorganic, such as chloride (Cl−), or organic, such as acetate (). Each ion can be either monatomic, such as sodium (Na+) and chloride (Cl−) in sodium chloride, or polyatomic, such as ammonium () and carbonate () ions in ammonium carbonate. Salts containing basic ions hydroxide (OH−) or oxide (O2−) are classified as bases, such as sodium hydroxide and potassium oxide. Individual ions within a salt usually have multiple near neighbours, so they are not considered to be part of molecules, but instead part of a continuous three-dimensional network. Salts usually form crystalline structures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant
Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars from carbon dioxide and water, using the green pigment chlorophyll. Exceptions are parasitic plants that have lost the genes for chlorophyll and photosynthesis, and obtain their energy from other plants or fungi. Most plants are multicellular organism, multicellular, except for some green algae. Historically, as in Aristotle's biology, the plant kingdom encompassed all living things that were not animals, and included algae and fungi. Definitions have narrowed since then; current definitions exclude fungi and some of the algae. By the definition used in this article, plants form the clade Viridiplantae (green plants), which consists of the green algae and the embryophytes or land plants (hornworts, liverworts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
