A mycotoxin 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.
The Nicolaou Taxol total synthesis, published by K. C. Nicolaou and his group in 1994 concerns the total synthesis of taxol. Taxol is an important drug in the treatment of cancer but also expensive because the compound is harvested from a scarce resource, namely the pacific yew.
Trichothecenes constitute a large group of chemically related mycotoxins. They are produced by fungi of the genera Fusarium, Myrothecium, Trichoderma, Podostroma, Trichothecium, Cephalosporium, Verticimonosporium, Stachybotrys and possibly others. Chemically, trichothecenes are a class of sesquiterpenes.
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.
Mycotoxicology is the branch of mycology that focuses on analyzing and studying the toxins produced by fungi, known as mycotoxins. In the food industry it is important to adopt measures that keep mycotoxin levels as low as practicable, especially those that are heat-stable. These chemical compounds are the result of secondary metabolism initiated in response to specific developmental or environmental signals. This includes biological stress from the environment, such as lower nutrients or competition for those available. Under this secondary path the fungus produces a wide array of compounds in order to gain some level of advantage, such as incrementing the efficiency of metabolic processes to gain more energy from less food, or attacking other microorganisms and being able to use their remains as a food source.
Penitrem A (tremortin) is an indole-diterpenoid mycotoxin produced by certain species of Aspergillus, Claviceps, and Penicillium, which can be found growing on various plant species such as ryegrass. Penitrem A is one of many secondary metabolites following the synthesis of paxilline in Penicillium crostosum. Penitrem A poisoning in humans and animals usually occurs through the consumption of contaminated foods by mycotoxin-producing species, which is then distributed through the body by the bloodstream. It bypasses the blood-brain barrier to exert its toxicological effects on the central nervous system. In humans, penitrem A poisoning has been associated with severe tremors, hyperthermia, nausea/vomiting, diplopia, and bloody diarrhea. In animals, symptoms of penitrem A poisoning has been associated with symptoms ranging from tremors, seizures, and hyperthermia to ataxia and nystagmus.
Paxilline is a toxic, tremorgenic diterpene indole polycyclic alkaloid molecule produced by Penicillium paxilli which was first characterized in 1975. Paxilline is one of a class of tremorigenic mycotoxins, is a potassium channel blocker, and is potentially genotoxic.
Roquefortine C is a mycotoxin that belongs to a class of naturally occurring 2,5-diketopiperazines produced by various fungi, particularly species from the genus Penicillium. It was first isolated from a strain of Penicillium roqueforti, a species commercially used as a source of proteolytic and lipolytic enzymes during maturation of the blue-veined cheeses, Roquefort, Danish Blue, Stilton and Gorgonzola.
Cyclochlorotine (CC), also known as islanditoxin, is a mycotoxin produced by the fungus Penicillium islandicum that causes liver damage and has carcinogenic properties. Japanese researchers confirmed that it was one of three strains of Penicillin fungi responsible for yellowed rice. It is listed as an IARC Group 3 carcinogen.
Secalonic acids are a group of xanthone derivatives closely related to ergoflavin and ergochrysin A that are collectively called ergochromes and belong to a class of mycotoxins initially isolated as major ergot pigments from the fungi Claviceps purpurea that grows parasitically on rye grasses. From early times and particularly in medieval Europe the consumption of grains containing ergot has repeatedly lead to mass poisonings known as ergotism which was caused by toxic ergot alkaloids and mycotoxins such as the ergochromes, due to contamination of flour by C. purpurea. A cluster of genes responsible for the synthesis of secalonic acids in C. purpurea has been identified. Secalonic acid D the enantiomer of secalonic acid A is a major environmental toxin, isolated from the fungus Penicillium oxalicum, and is a major microbial contaminant of freshly-harvested corn which causes toxicity through contamination of foodstuffs.
Penicillium brunneum is an anamorph fungus species of the genus of Penicillium which was isolated in imported rice an produces rugulosin a substance which is hepatocarcinogenic to mice and rats.
Penicillium islandicum is an anamorph species of the genus of Penicillium which produces luteoskyrin, simatoxin, cyclochlorotine (islanditoxin), rugulosin and chitosanase.
Penicillium persicinum is a species of fungus in the genus Penicillium which was isolated from soil from the Qinghai Province in China. Penicillium persicinum produces griseofulvin, lichexanthone, roquefortine C, roquefortine D, patulin and chrysogine
Penicillium resedanum is an anamorph species of fungus in the genus Penicillium which produces monorden.
Penicillium rugulosum is an anamorph species of fungus in the genus Penicillium which produces inulinase, luteoskyrin and (+) rugulosin.
Penicillium tulipae is a species of fungus in the genus Penicillium which produces penicillic acid, roquefortine C, roquefortine D, terrestric acid, glandicoline A, glandicoline B, meleagrin, oxaline, penitrem A and epineoxaline.
Penicillium viridicatum is a psychrophilic species of fungus in the genus, penicillic acid and citrinin. Penicillium viridicatum can spoil grapes and melons.
Lolitrem B is one of many toxins produced by a fungus called Epichloë festucae var. lolii), which grows in Lolium perenne. The fungus is symbiotic with the ryegrass; it doesn't harm the plant, and the toxins it produces kill insects that feed on ryegrass. Lolitrem B is one of these toxins, but it is also harmful to mammals. The shoots and flowers of infected ryegrass have especially high concentrations of lolitrem B, and when livestock eat too much of them, they get perennial ryegrass staggers. At low doses the animals have tremors, and at higher doses they stagger, and at higher yet doses the animals become paralyzed and die. The blood pressure of the animals also goes up. The effect of the lolitrem B comes on slowly and fades out slowly, as it is stored in fat after the ryegrass is eaten. The condition is especially common in New Zealand and Australia, and plant breeders there have been trying to develop strains of fungus that produce toxins only harmful to pests, and not to mammals.
Luteoskyrin is a carcinogenic mycotoxin with the molecular formula C30H22O12 which is produced by the mold Penicillium islandicum. Luteoskyrin has strong cytotoxic effects. Luteoskyrin can cause the yellow rice disease.
Gregatin B is a metabolite of the fungi Cephalosporium gregatum and Aspergillus panamensis with the molecular formula C14H18O4 Gregatin B is a weak antibiotic. Gregatin B was discovered in 1982 and has been the subject of total synthesis.
