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Fumonisin B4
Fumonisin B4 (or FB4) is a fumonisin mycotoxin produced mainly by the fungi ''Fusarium proliferatum'', ''Fusarium verticillioides'' (formerly ''Fusarium moniliforme''). Recently FB4 has been detected in fungi ''Aspergillus niger'' and in several ''Tolypocladium'' species. FB4 is similar to fumonisin B2 and fumonisin B3 but it is lacking a hydroxy group located gamma- to the amino substituent while lacking two hydroxy groups compared to fumonisin B1. Fumonisin B4 has been first published in 1991. Isomers Several isomers of Fumonisin B4 have been detected. A larger group is the partially hydrolysed form, denoted as PHFB4, which has been detected using High-performance_liquid_chromatography, HPLC-Ion trap mass spectrometer, ITMS. Another significant isomer is the 3-''epi''-FB4, which has been identified using Nuclear_magnetic_resonance#Chemistry, NMR, it has also been shown that this isomer occur 10-40% of the regular FB4 sample in nature. Toxicity Fumonisin B4 belongs to the class ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumonisin
The fumonisins are a group of mycotoxins derived from ''Fusarium'' and their Liseola section. They have strong structural similarity to sphinganine, the backbone precursor of sphingolipids. More specifically, it can refer to: * Fumonisin B1 * Fumonisin B2 * Fumonisin B3 * Fumonisin B4 The trichothecene (T-2) mycotoxins are a group of over 40 compounds produced by fungi of the genus ''Fusarium'', a common grain mold. The estrogenic metabolite, zearalenone, is also referred to as F-2 toxin. As the fumonisins appear to be non-genotoxic the possibility that they belong to another class of non-genotoxic carcinogens, the peroxisome proliferators, was investigated Genetic engineering is reported as a promising means of detoxifying mycotoxins. This approach may provide innovative solutions to the problem of fumonisin in corn. At least 15 different fumonisins have so far been reported and other minor metabolites have been identified, although most of them have not been shown to occur n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycotoxin
A mycotoxin (from the Greek μύκης , "fungus" and τοξίνη , "toxin") is a toxic secondary metabolite produced by organisms of kingdom Fungi and is capable of causing disease and death in both humans and other animals. The term 'mycotoxin' is usually reserved for the toxic chemical products produced by fungi that readily colonize crops. Examples of mycotoxins causing human and animal illness include aflatoxin, citrinin, fumonisins, ochratoxin A, patulin, trichothecenes, zearalenone, and ergot alkaloids such as ergotamine. One mold species may produce many different mycotoxins, and several species may produce the same mycotoxin. Production Most fungi are aerobic (use oxygen) and are found almost everywhere in extremely small quantities due to the diminute size of their spores. They consume organic matter wherever humidity and temperature are sufficient. Where conditions are right, fungi proliferate into colonies and mycotoxin levels become high. The reason for the pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusarium
''Fusarium'' is a large genus of filamentous fungi, part of a group often referred to as hyphomycetes, widely distributed in soil and associated with plants. Most species are harmless saprobes, and are relatively abundant members of the soil microbial community. Some species produce mycotoxins in cereal crops that can affect human and animal health if they enter the food chain. The main toxins produced by these ''Fusarium'' species are fumonisins and trichothecenes. Despite most species apparently being harmless (some existing on the skin as commensal members of the skin flora), some ''Fusarium'' species and subspecific groups are among the most important fungal pathogens of plants and animals. The name of ''Fusarium'' comes from Latin ''fusus'', meaning a spindle. Taxonomy The taxonomy of the genus is complex. A number of different schemes have been used, and up to 1,000 species have been identified at times, with approaches varying between wide and narrow concepts of specia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumonisin B2
Fumonisin B2 is a fumonisin mycotoxin produced by the fungi ''Fusarium verticillioides'' (formerly ''Fusarium moniliforme'') and ''Aspergillus niger''. It is a structural analog of fumonisin B3, while it is lacking one hydroxy group compared to fumonisin B1. Fumonisin B2 is more cytotoxic than fumonisin B1. Fumonisin B2 inhibits sphingosine acyltransferase. Fumonisin B2 and other fumonisins frequently contaminate maize Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American English, North American and Australian English), is a cereal grain first domesticated by indigenous peoples of Mexico, indigenous ... and other crops, while recently it has been shown using LC–MS/MS that FB2 can contaminate coffee beans as well. References Mycotoxins Enzyme inhibitors {{biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumonisin B3
The fumonisins are a group of mycotoxins derived from ''Fusarium'' and their Liseola section. They have strong structural similarity to sphinganine, the backbone precursor of sphingolipids. More specifically, it can refer to: * Fumonisin B1 * Fumonisin B2 * Fumonisin B3 * Fumonisin B4 The trichothecene (T-2) mycotoxins are a group of over 40 compounds produced by fungi of the genus ''Fusarium'', a common grain mold. The estrogenic metabolite, zearalenone, is also referred to as F-2 toxin. As the fumonisins appear to be non-genotoxic the possibility that they belong to another class of non-genotoxic carcinogens, the peroxisome proliferators, was investigated Genetic engineering is reported as a promising means of detoxifying mycotoxins. This approach may provide innovative solutions to the problem of fumonisin in corn. At least 15 different fumonisins have so far been reported and other minor metabolites have been identified, although most of them have not been shown to occur n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumonisin B1
Fumonisin B1 is the most prevalent member of a family of toxins, known as fumonisins, produced by several species of ''Fusarium'' molds, such as '' Fusarium verticillioides'', which occur mainly in maize (corn), wheat and other cereals. Fumonisin B1 contamination of maize has been reported worldwide at mg/kg levels. Human exposure occurs at levels of micrograms to milligrams per day and is greatest in regions where maize products are the dietary staple. Fumonisin B1 is hepatotoxic and nephrotoxic in all animal species tested. The earliest histological change to appear in either the liver or kidney of fumonisin-treated animals is increased apoptosis followed by regenerative cell proliferation. While the acute toxicity of fumonisin is low, it is the known cause of two diseases which occur in domestic animals with rapid onset: equine leukoencephalomalacia and porcine pulmonary oedema syndrome. Both of these diseases involve disturbed sphingolipid metabolism and cardiovascular dysfu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PubChem
PubChem is a database of chemical molecules and their activities against biological assays. The system is maintained by the National Center for Biotechnology Information (NCBI), a component of the National Library of Medicine, which is part of the United States National Institutes of Health (NIH). PubChem can be accessed for free through a web user interface. Millions of compound structures and descriptive datasets can be freely downloaded via FTP. PubChem contains multiple substance descriptions and small molecules with fewer than 100 atoms and 1,000 bonds. More than 80 database vendors contribute to the growing PubChem database. History PubChem was released in 2004 as a component of the Molecular Libraries Program (MLP) of the NIH. As of November 2015, PubChem contains more than 150 million depositor-provided substance descriptions, 60 million unique chemical structures, and 225 million biological activity test results (from over 1 million assay experiments performed on more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isomers
In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Isomers do not necessarily share similar chemical or physical properties. Two main forms of isomerism are structural or constitutional isomerism, in which ''bonds'' between the atoms differ; and stereoisomerism or spatial isomerism, in which the bonds are the same but the ''relative positions'' of the atoms differ. Isomeric relationships form a hierarchy. Two chemicals might be the same constitutional isomer, but upon deeper analysis be stereoisomers of each other. Two molecules that are the same stereoisomer as each other might be in different conformational forms or be different isotopologues. The depth of analysis depends on the field of study or the chemical and physical properties of interest. The English word "isomer" () is a bac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-performance Liquid Chromatography
High-performance liquid chromatography (HPLC), formerly referred to as high-pressure liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify each component in a mixture. It relies on pumps to pass a pressurized liquid solvent containing the sample mixture through a column filled with a solid adsorbent material. Each component in the sample interacts slightly differently with the adsorbent material, causing different flow rates for the different components and leading to the separation of the components as they flow out of the column. HPLC has been used for manufacturing (''e.g.'', during the production process of pharmaceutical and biological products), legal (''e.g.'', detecting performance enhancement drugs in urine), research (''e.g.'', separating the components of a complex biological sample, or of similar synthetic chemicals from each other), and medical (''e.g.'', detecting vitamin D levels in blood serum) purposes. Chrom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ion Trap Mass Spectrometer
A quadrupole ion trap or paul trap is a type of ion trap that uses dynamic electric fields to trap charged particles. They are also called radio frequency (RF) traps or Paul traps in honor of Wolfgang Paul, who invented the device and shared the Nobel Prize in Physics in 1989 for this work. It is used as a component of a mass spectrometer or a trapped ion quantum computer. Overview A charged particle, such as an atomic or molecular ion, feels a force from an electric field. It is not possible to create a static configuration of electric fields that traps the charged particle in all three directions (this restriction is known as Earnshaw's theorem). It is possible, however, to create an ''average'' confining force in all three directions by use of electric fields that change in time. To do so, the confining and anti-confining directions are switched at a rate faster than it takes the particle to escape the trap. The traps are also called "radio frequency" traps because the switc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Magnetic Resonance
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are perturbed by a weak oscillating magnetic field (in the near field) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. This process occurs near resonance, when the oscillation frequency matches the intrinsic frequency of the nuclei, which depends on the strength of the static magnetic field, the chemical environment, and the magnetic properties of the isotope involved; in practical applications with static magnetic fields up to ca. 20 tesla, the frequency is similar to VHF and UHF television broadcasts (60–1000 MHz). NMR results from specific magnetic properties of certain atomic nuclei. Nuclear magnetic resonance spectroscopy is widely used to determine the structure of organic molecules in solution and study molecular physics and crystals as well as non-crystalline materials. NM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxicity
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell ( cytotoxicity) or an organ such as the liver ( hepatotoxicity). By extension, the word may be metaphorically used to describe toxic effects on larger and more complex groups, such as the family unit or society at large. Sometimes the word is more or less synonymous with poisoning in everyday usage. A central concept of toxicology is that the effects of a toxicant are dose-dependent; even water can lead to water intoxication when taken in too high a dose, whereas for even a very toxic substance such as snake venom there is a dose below which there is no detectable toxic effect. Toxicity is species-specific, making cross-species analysis problematic. Newer paradigms and metrics are evolving to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
