– Mycotoxins
What is a mycotoxin?
Mycotoxin is made up of the two words myx (Greek for fungus) and toxicum (Latin for toxin). This term refers to metabolites derived from the use of nutrients (such as amino acids, pyruvate, acetate, etc.) in the cells of some food molds that cause poisoning in humans and animals leading to disease or death. کردن. Most mycotoxins found in food are produced from the three genera Aspergillus, Fusarium and Penicillium. They have a low molecular weight and a circular structure. Functional effects of fungal toxins are divided into four categories: severe, chronic, mutagenic and congenital defects.
1- Severe:
In the acute form, mycotoxins usually target the liver or kidneys, which in very severe cases can lead to death.
2- Chronic:
Some fungal toxins interfere with the body’s protein production, resulting in skin allergies or necrosis, weakened immune systems, cancers, especially in the liver, and some types of toxins damage the nervous system, causing mild shivering and High doses lead to brain damage or death.
3- Making mutations
4- Congenital defects
Some toxins interfere with gene replication, resulting in various cancers, reduced reproductive capacity, malformed fetuses, or fetal death.
Differences between fungal and bacterial toxins:
Bacterial toxins are usually in the form of large molecules in the form of polypeptides, proteins or lipopolysaccharides. Mycotoxins, on the other hand, have low molecular masses that range in mass from 50 to more than 500 daltons, depending on the structure of the single-to-multiple ring. Unlike bacterial toxins, fungal toxins are not primarily proteins and cannot be detected by the immune system.
Most mycotoxins found in food are produced from the three genera Aspergillus, Fusarium and Penicillium.
Types of mycotoxins
More than 300 fungal toxins have been reported, but only 6 of them are found in significant amounts in food sources.
2- 1- Aflatoxins
Aflatoxins are one of the most deadly types of fungal toxins that have effects such as causing cancer, genetic mutations, fetal death or birth defects, and suppressing the immune system. They are caused by some strains of Aspergillus flavusis and most strains of Aspergillus parasiticus. The production of aflatoxins is not limited to the storage period of food, but the onset of its formation and accumulation in food even before the harvest of agricultural products. Aspergillus is a mold fungus that normally lives on growing plants, but stresses such as drought provide the opportunity for the fungus to grow and produce high aflatoxins. Aflatoxins can enter the body through the gastrointestinal tract and respiratory tract and accumulate in tissues such as the liver, kidneys, gastrointestinal tract, immune system, lungs and nervous tissues. This group of toxins is divided into four main types B1, B2, G1 and G2 (from B1:, B2, G1 and G2). M1 and M2 (M1 and M2) are secondary toxins that are found in the milk of animals consuming aflatoxins. Group B are observed. The toxicity of aflatoxins is as follows: B1 ˃ M1 ˃ G1 ˃ B2 ˃ M2 ˃ G2.
2- 2- Trichotoxins
Trichostones originate from Fusarium species. More than 20 compounds are produced naturally from Fusariums, which have similar structures and include T2, neosolaniol, diacetyl nivalnol, dystoxypirpenal, nivalnol, deoxyivalenol, and fusarnone X. Deoxy nivalenol, or don vemi toxin, is the cause of poisoning in moldy corn poisoning and its symptoms include not eating, stopping weight gain and digestive disorders that will eventually lead to the death of the animal. Feeding high levels of T2 toxin for broilers can cause acute abdominal edema, colon bleeding, mouth ulcers, neurological disorders, and eventually death.
2- 3- زیرالنون
Ziralenone is an estrogenic compound also known as toxin F2. This toxin is made by Fusarium species. Ziralenone is usually found in wet corn in late fall and winter, as well as moldy dry alfalfa. The production of these toxins is enhanced in conditions of high humidity and low and medium temperature fluctuations. This type of fungal toxin usually causes poisoning in high amounts.
2- 4- Ochratoxin
Ocratoxins are produced by Aspergillus ukras and related species, as well as Penicillium verdi catum and some other species of Penicillium. The main toxin in this group of fungal toxins is ocratoxin A, which is a strong mycotoxin and causes kidney damage. From these toxins, incomplete mood-creating effects have been observed in poultry, especially hens.
2- 5- Fumensins
Fumensins are mostly made in Fusarium and Alternaria fungi and affect the liver and kidneys. These toxins also destroy the myelin sheath in the nervous system by inhibiting the production of sphingolipids. The safe level of fiumensins in broilers is 50 parts per million (ppm) and in poultry and laying hens is 15 parts per million.
2- 6- Ergot alkaloids
Ergot alkaloids are made in the species of Clovis fungi, which are considered plant pathogens. The history of acquaintance with this mycotoxin dates back to the Middle Ages, which caused poisoning in humans. Argot toxins include a variety of argosin, ergometrine, and clavin ergotamines, and the initial symptoms are similar to gangrene.
