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.
Aspergillus fumigatus is a species of fungus in the genus Aspergillus, and is one of the most common Aspergillus species to cause disease in individuals with an immunodeficiency.
Penicillium roqueforti is a common saprotrophic fungus in the genus Penicillium. Widespread in nature, it can be isolated from soil, decaying organic matter, and plants.
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.
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 with the presence of other toxins.
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.
The endocannabinoid system (ECS) is a biological system composed of endocannabinoids, which are neurotransmitters that bind to cannabinoid receptors, and cannabinoid receptor proteins that are expressed throughout the central nervous system and peripheral nervous system. The endocannabinoid system is still not fully understood, but may be involved in regulating physiological and cognitive processes, including fertility, pregnancy, pre- and postnatal development, various activity of immune system, appetite, pain-sensation, mood, and memory, and in mediating the pharmacological effects of cannabis. The ECS plays an important role in multiple aspects of neural functions, including the control of movement and motor coordination, learning and memory, emotion and motivation, addictive-like behavior and pain modulation, among others.
Cyclopiazonic acid (α-CPA), a mycotoxin and a fungal neurotoxin, is made by the molds Aspergillus and Penicillium. It is an indole-tetramic acid that serves as a toxin due to its ability to inhibit calcium-dependent ATPases found in the endoplasmic and sarcoplasmic reticulum. This inhibition disrupts the muscle contraction-relaxation cycle and the calcium gradient that is maintained for proper cellular activity in cells.
Virulence factors are cellular structures, molecules and regulatory systems that enable microbial pathogens to achieve the following:
A Janus molecule is a molecule which can represent both beneficial and toxic effects. The term Janus-faced molecule is derived from the ancient Roman god, Janus. Janus is depicted as having two faces; one facing the past and one facing the future. This is synonymous to a Janus molecule having two distinct purposes: a beneficial and a toxic purpose depending on its quantity.
Mycoestrogens are xenoestrogens produced by fungi. They are sometimes referred to as mycotoxins. Among important mycoestrogens are zearalenone, zearalenol and zearalanol. Although all of these can be produced by various Fusarium species, zearalenol and zearalanol may also be produced endogenously in ruminants that have ingested zearalenone. Alpha-zearalanol is also produced semisynthetically, for veterinary use; such use is prohibited in the European Union.
Zaragozic acids are a family of natural products produced by fungi. The first characterized zaragozic acids, A, B, and C were isolated from an unidentified sterile fungal culture, Sporormiella intermedia, and L. elatius, respectively. just outside the European city Zaragoza, Spain on the Jalón river. This family of natural products possesses a unique 4,8-dioxabicyclo[3.2.1]octane core, and vary in their 1-alkyl and their 6-acyl side chains.
Microbial toxins are toxins produced by micro-organisms, including bacteria, fungi, protozoa, dinoflagellates, and viruses. Many microbial toxins promote infection and disease by directly damaging host tissues and by disabling the immune system. Endotoxins most commonly refer to the lipopolysaccharide (LPS) or lipooligosaccharide (LOS) that are in the outer plasma membrane of Gram-negative bacteria. The botulinum toxin, which is primarily produced by Clostridium botulinum and less frequently by other Clostridium species, is the most toxic substance known in the world. However, microbial toxins also have important uses in medical science and research. Currently, new methods of detecting bacterial toxins are being developed to better isolate and understand these toxins. Potential applications of toxin research include combating microbial virulence, the development of novel anticancer drugs and other medicines, and the use of toxins as tools in neurobiology and cellular biology.
Aspergillus ochraceus is a mold species in the genus Aspergillus known to produce the toxin ochratoxin A, one of the most abundant food-contaminating mycotoxins, and citrinin. It also produces the dihydroisocoumarin mellein. It is a filamentous fungus in nature and has characteristic biseriate conidiophores. Traditionally a soil fungus, has now began to adapt to varied ecological niches, like agricultural commodities, farmed animal and marine species. In humans and animals the consumption of this fungus produces chronic neurotoxic, immunosuppressive, genotoxic, carcinogenic and teratogenic effects. Its airborne spores are one of the potential causes of asthma in children and lung diseases in humans. The pig and chicken populations in the farms are the most affected by this fungus and its mycotoxins. Certain fungicides like mancozeb, copper oxychloride, and sulfur have inhibitory effects on the growth of this fungus and its mycotoxin producing capacities.
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 nordicum is an anamorph species of fungus in the genus Penicillium which produces ochratoxin A. Penicillium nordicum contaminates protein rich foods and foods with high NaCl-konzentration. It is mostly found on dry-cured meat products and cheese products
Aspergillus parasiticus is a fungus belonging to the genus Aspergillus. This species is an unspecialized saprophytic mold, mostly found outdoors in areas of rich soil with decaying plant material as well as in dry grain storage facilities. Often confused with the closely related species, A. flavus, A. parasiticus has defined morphological and molecular differences. Aspergillus parasiticus is one of three fungi able to produce the mycotoxin, aflatoxin, one of the most carcinogenic naturally occurring substances. Environmental stress can upregulate aflatoxin production by the fungus, which can occur when the fungus is growing on plants that become damaged due to exposure to poor weather conditions, during drought, by insects, or by birds. In humans, exposure to A. parasiticus toxins can cause delayed development in children and produce serious liver diseases and/or hepatic carcinoma in adults. The fungus can also cause the infection known as aspergillosis in humans and other animals. A. parasiticus is of agricultural importance due to its ability to cause disease in corn, peanut, and cottonseed.
Mucor circinelloides is a dimorphic fungus belonging to the Order Mucorales. It has a worldwide distribution, found mostly in soil, dung and root vegetables. This species is described as not known to be able to produce mycotoxins, however it has been frequently reported to infect animals such as cattle and swine, as well as fowl, platypus and occasionally humans. Ketoacidotic patients are particularly at risk for infection by M. circinelloides.
Penicillin Roquefort toxin is a mycotoxin produced by the fungus Penicillium roqueforti. In 1973, PR toxin was first partially characterized by isolating moldy corn on which the fungi had grown. Although its lethal dose was determined shortly after the isolation of the chemical, details of its toxic effects were not fully clarified until 1982 in a study with mice, rats, anesthetized cats and preparations of isolated rat auricles.
Arthrinium is a genus of minute disease-causing fungi which belong to the family Apiosporaceae and which are parasitic on flowering plants such as sedges. These fungi have an anamorphic life cycle stage where spores are produced asexually in structures called conidia and a teleomorphic stage where sexual spores are produced in asci.
