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Stilbenoid
Stilbenoids are hydroxylated derivatives of stilbene. They have a C6–C2–C6 structure. In biochemical terms, they belong to the family of phenylpropanoids and share most of their biosynthesis pathway with chalcones. Most stilbenoids are produced by plants, and the only known exception is the antihelminthic and antimicrobial stilbenoid, 2-isopropyl-5- ''E'')-2-phenylvinylenzene-1,3-diol, biosynthesized by the Gram-negative bacterium '' Photorhabdus luminescens.'' Chemistry Stilbenoids are hydroxylated derivatives of stilbene and have a C6–C2–C6 structure. They belong to the family of phenylpropanoids and share most of their biosynthesis pathway with chalcones. Under UV irradiation, stilbene and its derivatives undergo intramolecular cyclization, called stilbene photocyclization to form dihydrophenanthrenes. Oligomeric forms are known as oligostilbenoids. Types ;Aglycones * Piceatannol in the roots of Norway spruces * Pinosylvin is a fungal toxin protecting wood f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligostilbenoid
Oligostilbenoids (oligo- or polystilbenes) are oligomeric forms of stilbenoids. Some molecules are large enough to be considered polyphenols and constitute a class of tannins. Examples Dimers * Ampelopsin A * Epsilon-viniferin * Pallidol * Quadrangularin A Trimers * α-Viniferin * Ampelopsin E * ''trans''-Diptoindonesin B * Gnetin H Tetramers * cajyphenol A * cajyphenol B * Flexuosol A * Hemsleyanol D * Hopeaphenol * Vaticanol B * R2-Viniferin (syn. Vitisin A) Modified * Diptoindonesin C can be isolated from the bark of '' Shorea pinanga'' Other * Diptoindonesin F can be isolated from the bark of ''Shorea gibbosa'' Glycosides * Diptoindonesin A Diptoindonesin A is a C- glucoside of ε-viniferin isolated from the two Dipterocarpaceae '' Shorea seminis'' and ''Dryobalanops aromatica ''Dryobalanops aromatica'', commonly known as Borneo camphor, camphor tree, Malay camphor, or Sumatran c ... References External links * {{oligostilbenoid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combretastatin
Combretastatin is a dihydrostilbenoid found in '' Combretum caffrum''. As a class Combretastatins are a class of natural phenols. A variety of different natural combretastatin molecules are present in the bark of '' Combretum caffrum'', commonly known as South African Bush Willow. Despite having a similar name, combretastatins are unrelated to statins, a family of cholesterol lowering drugs. Natural combretastatins Molecules that fall into the combretastatin family generally share 3 common structural features: a trimethoxy "A"-ring, a "B"-ring containing substituents often at C3' and C4', and ftenan ethene bridge between the two rings which provides necessary structural rigidity. Molecules with such an ethene bridge are also stilbenoids, molecules with a non-ethene bridge are dihydrostilbenoids. Molecules with C3' amino and hydroxyl substituents are very active, and molecules with C4' hydroxyl or methoxy substituents are also cytotoxic. Of the natural products presently kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resveratrol
Resveratrol (3,5,4′-trihydroxy-''trans''-stilbene) is a stilbenoid, a type of natural phenol, and a phytoalexin produced by several plants in response to injury or when the plant is under attack by pathogens, such as bacteria or fungi. Sources of resveratrol in food include the skin of grapes, blueberries, raspberries, mulberries, and peanuts. Although commonly used as a dietary supplement and studied in laboratory models of human diseases, there is no high-quality evidence that resveratrol improves lifespan or has a substantial effect on any human disease. Research Resveratrol has been studied for its potential therapeutic use, with little evidence of anti-disease effects or health benefits in humans. Cardiovascular disease There is no evidence of benefit from resveratrol in people who already have heart disease. A 2018 meta-analysis found no effect on systolic or diastolic blood pressure; a sub-analysis revealed a 2 mmHg decrease in systolic pressure only from res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resveratrol
Resveratrol (3,5,4′-trihydroxy-''trans''-stilbene) is a stilbenoid, a type of natural phenol, and a phytoalexin produced by several plants in response to injury or when the plant is under attack by pathogens, such as bacteria or fungi. Sources of resveratrol in food include the skin of grapes, blueberries, raspberries, mulberries, and peanuts. Although commonly used as a dietary supplement and studied in laboratory models of human diseases, there is no high-quality evidence that resveratrol improves lifespan or has a substantial effect on any human disease. Research Resveratrol has been studied for its potential therapeutic use, with little evidence of anti-disease effects or health benefits in humans. Cardiovascular disease There is no evidence of benefit from resveratrol in people who already have heart disease. A 2018 meta-analysis found no effect on systolic or diastolic blood pressure; a sub-analysis revealed a 2 mmHg decrease in systolic pressure only from res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterostilbene
Pterostilbene () (trans-3,5-dimethoxy-4-hydroxystilbene) is a stilbenoid chemically related to resveratrol. In plants, it serves a defensive phytoalexin role. Natural occurrence Pterostilbene is found in almonds, various ''Vaccinium'' berries (including blueberries), grape leaves and vines, and ''Pterocarpus marsupium'' heartwood. Safety and regulation Pterostilbene is considered to be a corrosive substance, is dangerous upon exposure to the eyes, and is an environmental toxin, especially to aquatic life. A randomized, double-blind, placebo-controlled of healthy human subjects given pterostilbene for 6–8 weeks, showed pterostilbene to be safe for human use at dosages up to 250 mg per day. Its chemical relative, resveratrol, received FDA GRAS status in 2007, and approval of synthetic resveratrol as a safe compound by the European Food Safety Authority (EFSA) in 2016. Pterostilbene differs from resveratrol by exhibiting increased bioavailability (80% compared to 20% in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampelopsin B
Ampelopsin B is a stilbenoid dimer found in ''Ampelopsis glandulosa ''Ampelopsis glandulosa'' is a species of plant native to China, Japan, India, Nepal, Myanmar, Vietnam, and the Philippines. Varieties Several varieties are distinguished: * var. ''hancei'' * var. ''kulingensis'' * var. ''glandulosa'' * var ...'' var. ''hancei'' (formerly ''Ampelopsis brevipedunculata'' var. ''hancei'').Chemical determination of the absolute structures of resveratrol dimers, ampelopsins A, B, D and F. Yoshiaki Takaya, Ke-Xu Yan, Kenji Terashima, Junko Ito and Masatake Niwa, Tetrahedron, 2002, 58, pages 7259–7265, References Stilbenoid dimers Ampelopsis {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3,5-Dihydroxy-4-isopropyl-trans-stilbene
Tapinarof, also known as benvitimod and sold under the brand name Vtama, is a medication used for the treatment of plaque psoriasis. The medication is applied to the skin. Besides its use in medicine, tapinarof is a naturally occurring compound found in bacterial symbionts of nematodes which has antibiotic properties. The medication acts as an aryl hydrocarbon receptor agonist. Tapinarof was approved for medical use in the United States in May 2022. Medical uses Tapinarof is indicated for the treatment of plaque psoriasis in adults. Society and culture Names Tapinarof is the International Nonproprietary Name (INN). Natural occurrence Tapinarof, also known as benvitimod, is a bacterial stilbenoid produced in '' Photorhabdus'' bacterial symbionts of ''Heterorhabditis'' nematodes. It is a product of an alternative ketosynthase-directed stilbenoid biosynthesis pathway. It is derived from the condensation of two β-ketoacyl thioesters. It is produced by the '' Photorhabdus lu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoalexins
Phytoalexins are antimicrobial substances, some of which are antioxidative as well. They are defined, not by their having any particular chemical structure or character, but by the fact that they are defensively synthesized ''de novo'' by plants that produce the compounds rapidly at sites of pathogen infection. In general phytoalexins are broad spectrum inhibitors; they are chemically diverse, and different chemical classes of compounds are characteristic of particular plant taxa. Phytoalexins tend to fall into several chemical classes, including terpenoids, glycosteroids and alkaloids, however the term applies to any phytochemicals that are induced by microbial infection. Function Phytoalexins are produced in plants to act as toxins to the attacking organism. They may puncture the cell wall, delay maturation, disrupt metabolism or prevent reproduction of the pathogen in question. Their importance in plant defense is indicated by an increase in susceptibility of plant tissue t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piceid
Piceid is a stilbenoid glucoside and is a major resveratrol derivative in grape juices. It can be found in the bark of ''Picea sitchensis''. It can also be isolated from ''Reynoutria japonica'' ( syn. ''Fallopia japonica''), the Japanese knotweed (syn. ''Polygonum cuspidatum''). Resveratrol can be produced from piceid via the mold ''Aspergillus oryzae''. as the fungus produces a potent beta-glucosidase. ''trans''-Piceid is the glucoside formed with ''trans''-resveratrol, while ''cis''-piceid is formed with ''cis''-resveratrol. ''trans''-Resveratrol-3-''O''-glucuronide is one of the two metabolites of ''trans''-piceid in rat. Resveratrol glucoside from transgenic alfalfa prevents aberrant crypt foci in mice.R See also * Resveratroloside Resveratroloside is a stilbenoid glucoside. It can be found in ''Paeonia lactiflora ''Paeonia lactiflora'' (Chinese peony, Chinese herbaceous peony, or common garden peony) is a species of herbaceous perennial flowering plant in the fami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astringin
Astringin is a stilbenoid, the 3-β-D-glucoside of piceatannol. It can be found in the bark of ''Picea sitchensis'' or ''Picea abies'' (Norway spruce). It is also present in ''Vitis vinifera'' cells cultures and in wine. See also *Phenolic compounds in wine The phenolic content in wine refers to the phenolic compounds—natural phenol and polyphenols—in wine, which include a large group of several hundred chemical compounds that affect the taste, color and mouthfeel of wine. These compounds include ... References Stilbenoid glycosides Phenol glucosides {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampelopsin A
Ampelopsin A is a resveratrol dimer found in ''Ampelopsis glandulosa ''Ampelopsis glandulosa'' is a species of plant native to China, Japan, India, Nepal, Myanmar, Vietnam, and the Philippines. Varieties Several varieties are distinguished: * var. ''hancei'' * var. ''kulingensis'' * var. ''glandulosa'' * var ...'' var. ''hancei'' (formerly ''A. brevipedunculata'' var. ''hancei'').Chemical determination of the absolute structures of resveratrol dimers, ampelopsins A, B, D and F. Yoshiaki Takaya, Ke-Xu Yan†, Kenji Terashima, Junko Ito and Masatake Niwa, Tetrahedron, Volume 58, Issue 36, 2 September 2002, Pages 7259–7265, References External links kanaya.naist.jp/knapsack_jsp Resveratrol oligomers Stilbenoid dimers Ampelopsis {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Metabolite
Secondary metabolites, also called specialised metabolites, toxins, secondary products, or natural products, are organic compounds produced by any lifeform, e.g. bacteria, fungi, animals, or plants, which are not directly involved in the normal growth, development, or reproduction of the organism. Instead, they generally mediate ecological interactions, which may produce a selective advantage for the organism by increasing its survivability or fecundity. Specific secondary metabolites are often restricted to a narrow set of species within a phylogenetic group. Secondary metabolites often play an important role in plant defense against herbivory and other interspecies defenses. Humans use secondary metabolites as medicines, flavourings, pigments, and recreational drugs. The term secondary metabolite was first coined by Albrecht Kossel, a 1910 Nobel Prize laureate for medicine and physiology in 1910. 30 years later a Polish botanist Friedrich Czapek described secondary metabolit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
