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Mycotoxins
A mycotoxin (from the Greek μύκης , "fungus" and τοξικός , "poisonous") is a toxic secondary metabolite produced by 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 diminutive 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 produc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichothecenes
Trichothecenes constitute a large group of chemically related mycotoxins. They are produced by Fungus, fungi of the genera ''Fusarium'', ''Myrothecium'', ''Trichoderma'', ''Podostroma'', ''Trichothecium'', ''Cephalosporium'', ', ''Stachybotrys'' (most in Hypocreales) and possibly others. Chemically, trichothecenes are a class of sesquiterpenes. All trichothecenes share the Cyclic compound, cyclic sesquiterpene structure but differ in the type of functional group attached to the carbon backbone. They are produced on many different grains such as wheat, Oat, oats, or maize by various ''Fusarium'' species including ''Gibberella zeae, F. graminearum'', ''Fusarium sporotrichioides, F. sporotrichioides'', ''F. poae,'' and ''Fusarium equiseti, F. equiseti''. Some moulds that produce trichothecene mycotoxins, such as ''Stachybotrys chartarum'', can grow in damp indoor environments. It has been found that macrocyclic trichothecenes produced by ''Stachybotrys chartarum, S. chartarum'' can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citrinin
Citrinin is a mycotoxin which is often found in food. It is a secondary metabolite produced by fungi that contaminates long-stored food and it can cause a variety of toxic effects, including kidney, liver and cell damage. Citrinin is mainly found in stored grains, but sometimes also in fruits and other plant products. History Citrinin was one of the many mycotoxins discovered by H. Raistrick and A.C. Hetherington in the 1930s. In 1941 H. Raistrick and G. Smith identified citrinin to have a broad antibacterial activity. After this discovery the interest in citrinin rose. However, in 1946 A.M. Ambrose and F. DeEds demonstrated that citrinin was toxic to mammals. As a result, the interest in citrinin decreased, but there still was a lot of research. In 1948 the chemical structure was found by W.B. Whalley and coworkers. Citrinin is a natural compound and it was first isolated from ''Penicillium citrinum'', but is also produced by other ''Penicillium'' species, such as the '' Monasc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungi
A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one of the kingdom (biology)#Six kingdoms (1998), traditional eukaryotic kingdoms, along with Animalia, Plantae, and either Protista or Protozoa and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of motility, mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aflatoxin
Aflatoxins are various toxicity, poisonous carcinogens and mutagens that are produced by certain Mold (fungus), molds, especially ''Aspergillus'' species such as ''Aspergillus flavus'' and ''Aspergillus parasiticus''. According to the USDA, "They are probably the best known and most intensively researched mycotoxins in the world." The fungi grow in soil, decaying vegetation and various staple food, staple foodstuffs and commodities such as hay, maize (corn), peanuts, coffee, wheat, millet, sorghum, cassava, rice, chili peppers, cottonseed, tree nuts, sesame seeds, sunflower seeds, and various cereal grains and oil seeds. In short, the relevant fungi grow on almost any crop or food. When such contaminated food is processed or consumed, the aflatoxins enter the general food supply. They have been found in both pet and human foods, as well as in feedstocks for agricultural animals. Animals fed contaminated food can pass aflatoxin transformation products into milk, milk products, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zearalenone
Zearalenone (ZEN), also known as RAL and F-2 mycotoxin, is a potent estrogenic metabolite produced by some ''Fusarium'' and '' Gibberella'' species. Specifically, the '' Gibberella zeae'', the fungal species where zearalenone was initially detected, in its asexual/ anamorph stage is known as ''Fusarium graminearum.'' Several ''Fusarium'' species produce toxic substances of considerable concern to livestock and poultry producers, namely deoxynivalenol, T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS) and zearalenone. Particularly, ZEN is produced by '' Fusarium graminearum'', '' Fusarium culmorum'', '' Fusarium cerealis'', '' Fusarium equiseti'', '' Fusarium verticillioides'', and '' Fusarium incarnatum''. Zearalenone is the primary toxin that binds to estrogen receptors, causing infertility, abortion or other breeding problems, especially in swine. Often, ZEN is detected together with deoxynivalenol in contaminated samples and its toxicity needs to be considered in combination ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspergillus Flavus
''Aspergillus flavus'' is a saprotrophic and pathogenic fungus with a cosmopolitan distribution. It is best known for its colonization of cereal grains, legumes, and tree nuts. Postharvest rot typically develops during harvest, storage, and/or transit. Its specific name '' flavus'' derives from the Latin meaning yellow, a reference to the frequently observed colour of the spores. ''A. flavus'' infections can occur while hosts are still in the field (preharvest), but often show no symptoms (dormancy) until postharvest storage or transport. In addition to causing preharvest and postharvest infections, many strains produce significant quantities of toxic compounds known as mycotoxins, which, when consumed, are toxic to mammals. ''A. flavus'' is also an opportunistic human and animal pathogen, causing aspergillosis in immunocompromised individuals. Hosts ''Aspergillus flavus'' is found globally as a saprophyte in soils and causes disease on many important agriculture crops. C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumonisins
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 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 naturally. In 2015, a unique class of non-aminated fumonisins was reported on grapes infected with ''Aspergillus welwitschiae'', although their toxicities have not yet been established. Other ''Fusarium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ochratoxin A
Ochratoxin A—a toxin produced by different ''Aspergillus'' and ''Penicillium'' species — is one of the most-abundant food-contaminating mycotoxins. It is also a frequent contaminant of water-damaged houses and of heating ducts. Human exposure can occur through consumption of contaminated food products, particularly contaminated grain and pork products, as well as coffee, wine grapes, and dried grapes. The toxin has been found in the tissues and organs of animals, including human blood and breast milk. Ochratoxin A, like most toxic substances, has large species- and sex-specific toxicological differences. Impact on human and animal health Carcinogenicity Ochratoxin A is potentially carcinogenic to humans ( Group 2B), and has been shown to be weakly mutagenic, possibly by induction of oxidative DNA damage. The evidence in experimental animals is sufficient to indicate carcinogenicity of ochratoxin A. It was tested for carcinogenicity by oral administration in mice and rats. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspergillus Parasiticus
''Aspergillus'' () is a genus consisting of several hundred mold species found in various climates worldwide. ''Aspergillus'' was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli. Viewing the fungi under a microscope, Micheli was reminded of the shape of an ''aspergillum'' (holy water sprinkler), from Latin ''spargere'' (to sprinkle), and named the genus accordingly. Aspergillum is an asexual reproduction, asexual spore-forming structure common to all ''Aspergillus'' species; around one-third of species are also known to have a sexual stage. While some species of ''Aspergillus'' are known to cause fungal infections, others are of commercial importance. Taxonomy Species In March 2010, ''Aspergillus'' covered 837 species of fungi. Notable species placed in Aspergillus include: * ''Aspergillus flavus'' is a notable plant pathogen impacting crop yields and a common cause of aspergillosis. * ''Aspergillus fumigatus'' is the most common cause of as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspergillus
'''' () is a genus consisting of several hundred mold species found in various climates worldwide. ''Aspergillus'' was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli. Viewing the fungi under a microscope, Micheli was reminded of the shape of an '' aspergillum'' (holy water sprinkler), from Latin ''spargere'' (to sprinkle), and named the genus accordingly. Aspergillum is an asexual spore-forming structure common to all ''Aspergillus'' species; around one-third of species are also known to have a sexual stage. While some species of ''Aspergillus'' are known to cause fungal infections, others are of commercial importance. Taxonomy Species In March 2010, ''Aspergillus'' covered 837 species of fungi. Notable species placed in Aspergillus include: * '' Aspergillus flavus'' is a notable plant pathogen impacting crop yields and a common cause of aspergillosis. * '' Aspergillus fumigatus'' is the most common cause of aspergillosis in individuals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtropics
The subtropical zones or subtropics are geographical and climate zones immediately to the north and south of the tropics. Geographically part of the temperate zones of both hemispheres, they cover the middle latitudes from to approximately 35° to 40° north and south. The horse latitudes lie within this range. Subtropical climates are often characterized by hot summers and mild winters with infrequent frost. Most subtropical climates fall into two basic types: humid subtropical (Köppen climate classification: Cfa/Cwa), where rainfall is often concentrated in the warmest months, for example Southeast China and the Southeastern United States, and dry summer or Mediterranean climate (Köppen climate classification: Csa/Csb), where seasonal rainfall is concentrated in the cooler months, such as the Mediterranean Basin or Southern California. Subtropical climates can also occur at high elevations within the tropics, such as in the southern end of the Mexican Plateau an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
