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Pinosylvin
Pinosylvin is an organic compound with the formula C6H5CH=CHC6H3(OH)2. A white solid, it is related to trans-stilbene, but with two hydroxy groups on one of the phenyl substituents. It is very soluble in many organic solvents, such as acetone. Occurrence Pinosylvin is produced in plants in response to fungal infections, ozone-induced stress, and physical damage for example. It is a fungitoxin protecting the wood from fungal infection. It is present in the heartwood of ''Pinaceae'' and also found in ''Gnetum cleistostachyum''. Injected in rats, pinosylvin undergoes rapid glucuronidation and a poor bioavailability. Biosynthesis Pinosylvin synthase, an enzyme, catalyzes the biosynthesis of pinosylvin from malonyl-CoA and cinnamoyl-CoA: :3 malonyl-S-CoA + cinnamoyl-S-CoA → 4 CoA-SH + pinosylvin + 4 CO2 This biosynthesis is noteworthy because plant biosyntheses employing cinnamic acid as a starting point are rare compared to the more common use of ''p''-coumaric acid. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinosylvin Synthase
In enzymology, a pinosylvin synthase () is an enzyme that catalyzes the chemical reaction :3 malonyl-CoA + cinnamoyl-CoA \rightleftharpoons 4 CoA + pinosylvin + 4 CO2 Thus, the two substrates of this enzyme are malonyl-CoA and cinnamoyl-CoA, whereas its 3 products are CoA, pinosylvin, and CO2. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is malonyl-CoA:cinnamoyl-CoA malonyltransferase (cyclizing). Other names in common use include stilbene synthase, and pine stilbene synthase. This enzyme participates in phenylpropanoid biosynthesis The biosynthesis of phenylpropanoids involves a number of enzymes. From amino acids to cinnamates In plants, all phenylpropanoids are derived from the amino acids phenylalanine and tyrosine. Phenylalanine ammonia-lyase (PAL, a.k.a. phenylalanine/t .... References * EC 2.3.1 Enzymes of unknown structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curcumin
Curcumin is a bright yellow chemical produced by plants of the ''Curcuma longa'' species. It is the principal curcuminoid of turmeric (''Curcuma longa''), a member of the ginger family, Zingiberaceae. It is sold as a herbal supplement, cosmetics ingredient, food flavoring, and food coloring. Chemically, curcumin is a polyphenol, more particularly a diarylheptanoid, belonging to the group of curcuminoids, which are natural phenol, phenolic pigments responsible for the yellow color of turmeric. Laboratory and clinical research have not confirmed any medical use for curcumin. It is difficult to study because it is both unstable and poorly bioavailable. It is unlikely to produce useful leads for drug development as a lead compound. History Curcumin was named in 1815 when Henri Auguste Vogel and Pierre Joseph Pelletier reported the first isolation of a "yellow coloring-matter" from the rhizomes of turmeric. Later, it was found to be a mixture of resin and turmeric oil. In 1910, Mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinnamoyl-CoA
Cinnamoyl-coenzyme A is an intermediate in the Phenylpropanoids metabolism, phenylpropanoid metabolic pathway. Enzymes using cinnamoyl-coenzyme A * Cinnamoyl-CoA reductase, an enzyme that catalyzes the chemical reaction cinnamaldehyde + CoA + NADP+ → cinnamoyl-CoA + NADPH + H+ * Pinosylvin synthase, an enzyme that catalyzes the chemical reaction 3 malonyl-CoA + cinnamoyl-CoA → 4 CoA + pinosylvin + 4 CO2 * Cinnamoyl-CoA:phenyllactate CoA-transferase, an enzyme that catalyzes the chemical reaction (E)-cinnamoyl-CoA + (R)-phenyllactate → (E)-cinnamate + (R)-phenyllactyl-CoA References Thioesters of coenzyme A Cinnamate esters {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heartwood
Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or more broadly to include the same type of tissue elsewhere, such as in the roots of trees or shrubs. In a living tree, it performs a mechanical-support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients among the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, woodchips, or fibers. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. More recently it emerged as a feedstock for the production of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gnetum Cleistostachyum
''Gnetum cleistostachyum'' is a liana species in the ''Sessiles'' subsection of the genus ''Gnetum'' described from South East Yunnan. The name is still invalid and efloras states it is advisable to postpone validating it until more complete collections, particularly with seeds, can be studied. The stilbene derivatives, , gnetucleistol B, B and gnetucleistol C, C, gnetifolin A, p-hydroxycinnamic acid, piceatannol, resveratrol, , , , the stilbenolignans, , , , and , gnetucleistol D (2-methoxyoxyresveratrol), gnetucleistol E (3-methoxy-isorhapontigenin), rhapontigenin, isorhapontigenin, 4-methoxyresveratrol and pinosylvin can be found in ''G. cleistostachyum''. References External links Gnetaceae Plants described in 1975 Flora of Yunnan {{gymnosperm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinnamic Acid
Cinnamic acid is an organic compound with the formula phenyl, C6H5-CH=CH-Carboxylic acid, COOH. It is a white crystalline compound that is slightly soluble in water, and freely soluble in many organic solvents. Classified as an unsaturated carboxylic acid, it occurs naturally in a number of plants. It exists as both a Cis–trans isomerism, ''cis'' and a ''trans'' isomer, although the latter is more common. The ''cis''-isomer is called allocinnamic acid. Occurrence and production Biosynthesis Cinnamic acid is a central intermediate in the biosynthesis of a myriad of natural products including lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and phenylpropanoids. Its biosynthesis involves the action of the enzyme phenylalanine ammonia-lyase (PAL) on phenylalanine. Natural occurrence It is obtained from oil of cinnamon, or from balsams such as storax. It is also found in shea butter. Cinnamic acid has a honey-like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P-Coumaric Acid
''p''-Coumaric acid is an organic compound with the formula HOC6H4CH=CHCO2H. It is one of the three isomers of coumaric acid. It is a white solid that is only slightly soluble in water but very soluble in ethanol and diethyl ether. Natural occurrences It is a precursor to many natural products, especially Monolignol, lignols, precursors to the woody mass that comprise many plants. Of the myriad occurrences, ''p''-coumaric acid can be found in ''Gnetum cleistostachyum''. In food ''p''-Coumaric acid can be found in a wide variety of edible plants and fungi such as peanuts, navy beans, tomatoes, carrots, basil and garlic. It is found in wine and vinegar. It is also found in barley grain. ''p''-Coumaric acid from pollen is a constituent of honey. Derivatives p-Coumaric acid glucoside, ''p''-Coumaric acid glucoside can also be found in commercial breads containing flaxseed. Diesters of ''p''-coumaric acid can be found in carnauba wax. Biosynthesis It is biosynthesized from c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malonyl-CoA
Malonyl-CoA is a coenzyme A derivative of malonic acid. Biosynthesis Malonyl-CoA cannot cross membranes and there is no known malonyl-CoA import mechanism. The biosynthesis therefore takes place locally: * cytosol: Malonyl-CoA is formed by carboxylating acetyl-CoA using the highly regulated enzyme acetyl-CoA carboxylase 1 (ACC1). One molecule of acetyl-CoA joins with a molecule of bicarbonate, requiring energy rendered from ATP. * Mitochondrial outer membrane: Malonyl-CoA is formed by carboxylating acetyl-CoA using the highly regulated enzyme acetyl-CoA carboxylase 2 (ACC2). The reaction is the same as with ACC1. * mitochondrial matrix: Malonyl-CoA is formed in coordinated fashion by mtACC1, a mitochondrial isoform of ACC1, and acyl-CoA synthetase family member 3 (ACSF3), a mitochondrial malonyl-CoA synthetase. MtACC1, like cytosolic ACC1 catalyses the carboxylation of acetyl-CoA, while ACSF3 catalyses the thioesterification of malonate to coenzyme A. The latter serves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioavailability
In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation. By definition, when a medication is administered intravenously, its bioavailability is 100%. However, when a medication is administered via routes other than intravenous, its bioavailability is lower due to intestinal epithelium absorption and first-pass metabolism. Thereby, mathematically, bioavailability equals the ratio of comparing the area under the plasma drug concentration curve versus time (AUC) for the extravascular formulation to the AUC for the intravascular formulation. AUC is used because AUC is proportional to the dose that has entered the systemic circulation. Bioavailability of a drug is an average value; to take population variability into account, deviation range is shown as ±. To ensure that the drug taker who has poor absorption is dosed appropriately, the bottom value of the deviation range is employed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trans-stilbene
(''E'')-Stilbene, commonly known as ''trans''-stilbene, is an organic compound represented by the condensed structural formula CHCH=CHCH. Classified as a diarylethene, it features a central ethylene moiety with one phenyl group substituent on each end of the carbon–carbon double bond. It has an (''E'') stereochemistry, meaning that the phenyl groups are located on opposite sides of the double bond, the opposite of its geometric isomer, ''cis''-stilbene. ''Trans''-stilbene occurs as a white crystalline solid at room temperature and is highly soluble in organic solvents. It can be converted to ''cis''-stilbene photochemically, and further reacted to produce phenanthrene. Stilbene was discovered in 1843 by the French chemist Auguste Laurent. The name "stilbene" is derived from the Greek word ''στίλβω'' (''stilbo''), which means "I shine", on account of the lustrous appearance of the compound. Isomers Stilbene exists as two possible stereoisomers. One is ''trans''-1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
