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Pinoresinol
Pinoresinol is a tetrahydrofuran lignan found in '' Styrax sp.'', '' Forsythia suspensa, and in Forsythia koreana''. It is also found in the caterpillar of the cabbage butterfly, '' Pieris rapae'' where it serves as a defence against ants. In food, it is found in sesame seed, in '' Brassica'' vegetables and in olive oil. Pinoresinol has also been found to be toxic to larvae of the milkweed bug '' Oncopeltus fasciatus'' and of the haematophagous insect '' Rhodnius prolixus'', which is a vector of chagas disease. Currently, pinoresinol is isolated from plants with low efficiency and low yield. Biosynthesis A first dirigent protein was discovered in '' Forsythia intermedia''. This protein has been found to direct the stereoselective biosynthesis of (+)-pinoresinol from coniferyl alcohol monomers. Recently, a second, enantiocomplementary dirigent protein was identified in ''Arabidopsis thaliana'', which directs enantioselective synthesis of (-)-pinoresinol. Pharmacology Pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dirigent Protein
Dirigent proteins are members of a class of proteins which dictate the stereochemistry of a compound synthesized by other enzymes. The first dirigent protein was discovered in '' Forsythia intermedia''. This protein has been found to direct the stereoselective biosynthesis of (+)-pinoresinol from coniferyl alcohol monomers: Lignan biosynthesis is catalysed by oxidative enzymes. In the test tube the reaction results in a heterogeneous mixture of dimeric compounds. When a dirigent protein is present during the reaction, one stereoisomer of one compound is highly enriched. Dirigent proteins appear to possess no oxidative radical forming activity of their own; in the absence of oxidative enzyme, no reaction will occur. Recently, a second, enantiocomplementary dirigent protein was identified in ''Arabidopsis thaliana'', which directs enantioselective synthesis of (-)-pinoresinol. Activity In lignan biosynthesis, oxidative enzymes perform proton coupled electron transfer to remo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Stereoselective Biosynthesis
In chemistry, stereoselectivity is the property of a chemical reaction in which a single reactant forms an unequal mixture of stereoisomers during a non- stereospecific creation of a new stereocenter or during a non-stereospecific transformation of a pre-existing one. The selectivity arises from differences in steric and electronic effects in the mechanistic pathways leading to the different products. Stereoselectivity can vary in degree but it can never be total since the activation energy difference between the two pathways is finite: both products are at least possible and merely differ in amount. However, in favorable cases, the minor stereoisomer may not be detectable by the analytic methods used. An enantioselective reaction is one in which one enantiomer is formed in preference to the other, in a reaction that creates an optically active product from an achiral starting material, using either a chiral catalyst, an enzyme or a chiral reagent. The degree of selectivity is me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Coniferyl Alcohol
Coniferyl alcohol is an organic compound with the formula HO(CH3O)C6H3CH=CHCH2OH. A colourless or white solid, it is one of the monolignols, produced via the phenylpropanoid biochemical pathway. When copolymerized with related aromatic compounds, coniferyl alcohol forms lignin or lignans. Coniferin is a glucoside of coniferyl alcohol. Coniferyl alcohol is an intermediate in biosynthesis of eugenol and of stilbenoids and coumarin. Gum benzoin contains significant amount of coniferyl alcohol and its esters. It is found in both gymnosperm and angiosperm plants. Sinapyl alcohol and paracoumaryl alcohol, the other two lignin monomers, are found in angiosperm plants and grasses. Occurrence Coniferyl alcohol is produced from coniferyl aldehyde by the action of dehydrogenase enzymes. It is a queen retinue pheromone (QRP), a type of honey bee pheromone found in the mandibular glands. In '' Forsythia intermedia'' a dirigent protein was found to direct the stereoselective b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Sesame
Sesame (; ''Sesamum indicum'') is a plant in the genus '' Sesamum'', also called benne. Numerous wild relatives occur in Africa and a smaller number in India. It is widely naturalized in tropical regions around the world and is cultivated for its edible seeds, which grow in pods. World production in 2018 was , with Sudan, Myanmar, and India as the largest producers. Sesame seed is one of the oldest oilseed crops known, domesticated well over 3,000 years ago. ''Sesamum'' has many other species, most being wild and native to sub-Saharan Africa. ''S. indicum,'' the cultivated type, originated in India. It tolerates drought conditions well, growing where other crops fail. Sesame has one of the highest oil contents of any seed. With a rich, nutty flavor, it is a common ingredient in cuisines around the world. Like other foods, it can trigger allergic reactions in some people and is one of the nine most common allergens outlined by the Food and Drug Administration. Etymology Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lignan
The lignans are a large group of low molecular weight polyphenols found in plants, particularly seeds, whole grains, and vegetables. The name derives from the Latin word for "wood". Lignans are precursors to phytoestrogens. They may play a role as antifeedants in the defense of seeds and plants against herbivores. Biosynthesis and metabolism Lignans and lignin differ in their molecular weight, the former being small and soluble in water, the latter being high polymers that are undigestable. Both are polyphenolic substances derived by oxidative coupling of monolignols. Thus, most lignans feature a C18 cores, resulting from the dimerization of C9 precursors. The coupling of the lignols occurs at C8. Eight classes of lignans are: "furofuran, furan, dibenzylbutane, dibenzylbutyrolactone, aryltetralin, arylnaphthalene, dibenzocyclooctadiene, and dibenzylbutyrolactol." Many lignans are metabolized by mammalian gut microflora, producing so-called enterolignans. Food sources Fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Styrax
''Styrax'' (common names storax or snowbell) is a genus of about 130 species of large shrubs or small trees in the family Styracaceae, mostly native to warm temperate to tropical regions of the Northern Hemisphere, with the majority in eastern and southeastern Asia, but also crossing the equator in South America.Fritsch ''et al.'' (2001) The resin obtained from the tree is called benzoin or storax (not to be confused with the ''Liquidambar'' storax balsam), often used as a vanilla-like component in perfumery. The genus ''Pamphilia'', sometimes regarded as distinct, is now included within ''Styrax'' based on analysis of morphological and DNA sequence data. The spicebush (''Lindera benzoin'') is a different plant, in the family Lauraceae. Styrax trees grow to 2–14 m tall, and have alternate, deciduous or evergreen simple ovate leaves 1–18 cm long and 2–10 cm broad. The flowers are pendulous, with a white 5–10-lobed corolla, produced 3–30 together on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Forsythia Suspensa
''Forsythia suspensa'', commonly known as weeping forsythia or golden-bell, is a species of flowering plant in the family Oleaceae. It is native to China. Taxonomy The Latin epithet of ''suspensa'' is derived from ''suspensus'' meaning suspended. It was first described and published in Enum. Pl. Obs. Vol.1 on page 39 in 1804. Description ''Forsythia suspensa'' is a deciduous shrub that grows up to tall. Its flowers are golden-yellow and they bloom March to April. Leaves are green in color, broadly-ovate, and simple. It can be grown as a weeping shrub on stream banks and can be identified by its pale flowers. Garden cultivars can be found. It is a spring flowering shrub, with yellow flowers. It is grown and prized for its toughness. Before ''Forsythia × intermedia'' was known as a true wild Chinese species, ''F. suspensa'' was considered one of its parents. Distribution and habitat ''Forsythia suspensa'' is native to China. It is introduced in Japan, Spain, Bulgaria, Czechi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Olive Oil
Olive oil is a vegetable oil obtained by pressing whole olives (the fruit of ''Olea europaea'', a traditional Tree fruit, tree crop of the Mediterranean Basin) and extracting the oil. It is commonly used in cooking for frying foods, as a condiment, or as a salad dressing. It can also be found in some cosmetics, pharmaceuticals, soaps, and fuels for traditional oil lamps. It also has additional uses in some religions. The olive is one of three core food plants in Mediterranean cuisine, with wheat and grapes. Olive trees have been cultivated around the Mediterranean since the 8th millennium BC. In 2022, Spain was the world's largest producer, manufacturing 24% of the world's total. Other large producers were Italy, Greece, and Turkey, collectively accounting for 59% of the global market. The composition of olive oil varies with the cultivar, altitude, time of harvest, and extraction process. It consists mainly of oleic acid (up to 83%), with smaller amounts of other fatty acids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Extra Virgin Olive Oil
Olive oil is a vegetable oil obtained by pressing whole olives (the fruit of ''Olea europaea'', a traditional tree crop of the Mediterranean Basin) and extracting the oil. It is commonly used in cooking for frying foods, as a condiment, or as a salad dressing. It can also be found in some cosmetics, pharmaceuticals, soaps, and fuels for traditional oil lamps. It also has additional uses in some religions. The olive is one of three core food plants in Mediterranean cuisine, with wheat and grapes. Olive trees have been cultivated around the Mediterranean since the 8th millennium BC. In 2022, Spain was the world's largest producer, manufacturing 24% of the world's total. Other large producers were Italy, Greece, and Turkey, collectively accounting for 59% of the global market. The composition of olive oil varies with the cultivar, altitude, time of harvest, and extraction process. It consists mainly of oleic acid (up to 83%), with smaller amounts of other fatty acids includi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Tetrahydrofuran
Tetrahydrofuran (THF), or oxolane, is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specifically a cyclic ether. It is a colorless, water- miscible organic liquid with low viscosity. It is mainly used as a precursor to polymers. Being polar and having a wide liquid range, THF is a versatile solvent. It is an isomer of another solvent, butanone. Production About 200,000 tonnes of tetrahydrofuran are produced annually. The most widely used industrial process involves the acid-catalyzed dehydration of 1,4-Butanediol, 1,4-butanediol. Ashland Inc., Ashland/ISP is one of the biggest producers of this chemical route. The method is similar to the production of diethyl ether from ethanol. The butanediol is derived from Condensation reaction, condensation of acetylene with formaldehyde followed by hydrogenation. DuPont developed a process for producing THF by oxidizing Butane#Isomers, ''n''-butane to crude maleic anhydride, follow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Activity Of Dirigent Protein
Activity may refer to: * Action (philosophy), in general * Human activity: human behavior, in sociology behavior may refer to all basic human actions, economics may study human economic activities and along with cybernetics and psychology may study their modulation * In Semantics, a type of Aktionsart * Recreation, or activities of leisure * The Aristotelian concept of energeia, Latinized as ''actus'' * Activity (UML), a major task in Unified Modeling Language * ''Activity'', the rate of catalytic activity, such as enzyme activity (enzyme assay), in physical chemistry and enzymology * Thermodynamic activity, the effective concentration of a solute for the purposes of mass action * Activity (project management) * Activity, the number of radioactive decays per second * Activity (software engineering) * Activity (soil mechanics) * , an aircraft carrier of the Royal Navy * "Activity", a song by Way Out West from ''Intensify'' *Cultural activities, activities referred to culture. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Enterolignan
Enterolignans are organic compounds formed by the action of gut microflora on lignans. They are thus the products of the combined action of both plants and of the animal gut. Prominent enterolignans are enterodiol Enterodiol is an organic compound with the formula OC6H4CH2CH(CH2OH)sub>2. It is formed by the action of intestinal bacteria on lignan The lignans are a large group of low molecular weight polyphenols found in plants, particularly seeds, ... and enterolactone. Enterolignans are also called "mammalian lignans", although that term is self-contradictory since mammals do not produce lignans. Enterolignans have attracted intense attention because of their potential beneficial roles in nutrition. Elevated levels of enterodiol in urine are attributed consumption of tea and other lignan-rich foods. References Polyols Lignans 3-Hydroxyphenyl compounds {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
