Toxic effect of poisonous mushrooms
By the nature of the effect of poisonous fungi on humans, they can be divided into several groups.
First group
Toxic fungi with local( local) irritant effect, usually causing a disturbance in the functions of the digestive system. Many fungi that form toxins of this group cause mild poisoning, which do not pose a danger to life and usually last for 2-4 days. This group includes champignons( red and variegated), satanic mushroom, false raincoats, some types of russula and mlechniki with acrid taste, undercooked honey mushrooms( real), etc. The toxic substances of this group of mushrooms cause gastrointestinal disorders.
Symptoms of poisoning: weakness, sweating, abdominal pain, nausea, diarrhea, vomiting, sometimes fainting, - appear sometimes after 15 minutes, and at the latest - 1-2 hours after eating mushroom food.
However, a group of fungi that cause digestive system disorders include separate species that can cause life-threatening poisoning. These include the Tiger Brigade, some species of entol. In adult healthy people, toxicity usually ends in complete recovery. It is only necessary to rinse the stomach in time and take the medicines prescribed by the doctor.
However, in children and people weakened by illness, severe complications and even death may occur.
The second group
Poisonous fungi containing toxins of neurotropic action. The toxic substances of the fungi of this group cause, in the first place, disturbances in the activity of the central nervous system. This group is quite large. Currently, it includes many species of fly agaric( greyish-shaped, panther, pineal), some types of fiber, govorushke, ryadovok, entolom, as well as syvak and russula emetic. The group of hallucinogenic fungi includes fungi of the genus psilocybe( psilotsibe polulansetovidnaya) and some species from the family of stropharia( Fig.).
Fig. Psilotsibe
From the history of the discovery of neurotropic toxins For the first time the alkaloid of neurotropic action, which in its influence is close to acetylcholine and called muscarin, was discovered in red fly agaric. The first researchers of muscarin - German toxicologists Schmiedeberg and Koppe - assumed that it is the main poisonous substance of red fly agaric. However, subsequently it turned out that muscarin contains very little in muscaria( from 0.00033 to 0.0016% of crude weight of fungus), whereas in other species the amount of this substance is much greater. So, in Patuillard's fiber, muscarin is 25 times larger( up to 0.037%) than in red fly agaric.
Studies of toxins of red mushroom were started in the middle of the XIX century. In 1869 the German researchers Schmiedeberg and Koppe isolated an alkaloid from the fungus. The new substance was called muscarin. The lethal dose of this toxin to humans is 300-350 mg. This amount is contained in 40-80 g of Patuillard fiber and in 2-4 kg of fly agaric.
When muscarin acts after 30 minutes, at most after 2 hours, there is a strong contraction of the pupils, slows down the pulse and respiration, lowers blood pressure, increases the secretory activity of the sweat glands and mucous membranes of the nose and mouth. Later, hallucinations, attacks of laughter or crying, loss of consciousness and indigestion are observed.
As a result of further research, in addition to muscarin, 3 more active compounds with psychotropic action have been discovered: muscasone, isothenic acid and muscimol. It is this group of toxins that causes the characteristic symptoms of poisoning with red fly agaric. Muscimol, a derivative of zoetenic acid, is the main toxin of red mushroom, the content of which in this fungus ranges from 0.03 to 0.1% of the weight of fresh mushrooms. Later these toxins were found in other poisonous mushrooms: zhenotenic acid is found in fly agaric pine and panther;tricholomic acid, which is a derivative of zoebenic acid, in some species of ryadovok. A rather high concentration of toxins with strongly pronounced psychotropic action of an unknown chemical structure is found in the pochkoid and porphyry fly agarics.
When poisoning with muscarin and its derivatives, the stomach and intestines are cleaned and medicines are given to relieve agitation and normalize cardiac activity and respiration. Very effective at poisoning with muscarin atropine, which quickly restores the normal functioning of the heart. With timely provision of first aid and treatment in the hospital, recovery occurs in 2-4 days.
Mushroom-hallucinogens
Mushrooms of the genus psilocybe( psilotsibe polulansetovidnaya) and some representatives of the stropharia( stanza of Hornemann( Fig.), Etc.) possess a strong hallucinogenic effect.
Fig. Stropharia Gornemann
The history of the discovery of toxins of the genus psilocyibe is interesting. It is associated with the conquest of the indigenous peoples of Central and South America. In the manuscripts of the 16th century, which tell of the conquests of the conquistadors, there are references to the divine fungus "teonanacatl", which American Indians used in ritual ceremonies. During excavations in Guatemala, stone sculptures depicting mythical creatures with mushrooms rising above them were discovered. Scientists who studied the mountainous regions of Mexico, once attended the ritual, preserved there since ancient times. Before him, the participants of the magic act used special mushrooms, and then fell into a state of trance and hallucinations. Later, the French mycologist R. Ayma found out that the ritual mushrooms of ancient Indian tribes are a new species from the psilocybe genus.
In the future, from the fungus by chemical synthesis were identified close psychotropic compounds - psilocybin and psilocin, studied their structure and properties.
Psilocibin, found in a large number of fungi of the genus psilocybe and the family of stropharia, is not toxic, but a dose of 1 mg 20 minutes after use causes a person intoxicated. A dose of 4 mg leads to a state of detachment from reality, and when taking high doses( up to 12 mg) hallucinations occur, there are profound changes in the psyche. In addition to hallucinogenic substances, 2 alkaloids that violate the activity of the cerebral cortex are found in fungi of the psilocybia species.
At the same time, psilocybin in small doses is used in medical practice for the treatment of mental illness: in patients suffering from memory loss, memories come to life, a feeling of relaxedness, fear and fear disappear.
The third group
Poisonous hat-shaped fungi with pronounced plasmotoxic effect. For the fungi of this group is also characterized by a long latent( latent) period of toxins on the body. This group includes a pale toadstool and the fly-agarics that are close to it, as well as a spider's net of orange-red, false honey agarics - sulfur yellow and brick red, some types of fiber, stitching and lobes.
The action of the toxins of the pale toadstool
The most dangerous fungus of this group is pale toadstool: the toxins contained in it even in a very small dose are fatal to humans. The poisonous pallor grebe and some species of fly agaric( smelly and springy) is determined by the content of phallo- and amatoxins in them.
Phallotoxins are a complex consisting of such components as phalloidin, phallisin, phallon, phallin, phallocin, phallizine, etc.
The danger of toxins contained in a pale toadstool is that, after getting into the stomach and then into the blood, poisonoussubstances for a long time( up to 48 hours or more) do not cause obvious symptoms of poisoning. And even after the absorption of toxins into the blood, when they reach some organs, the violation of their activity first flows imperceptibly. This is the so-called latent( latent) period. The danger is that there are no visible symptoms, whereas toxins cause irreversible changes in the internal organs, for example, lead to necrosis of the liver or kidneys.
Signs of poisoning become pronounced only after toxins enter the brain and begin to affect the nerve centers that regulate the functions of individual organs. As a result of strengthening the activity of the musculature of the intestine, gastric juice and mucus begin to be intensively isolated, vomiting and diarrhea begin. The body is dehydrated, the blood condenses, there is an unquenchable thirst and cramps, lips and nails turn blue, hands and feet become cold. The next stage is the drop in blood pressure. This happens because the poisons paralyze the nerves that regulate the blood vessels, resulting in blood in the vessels.
The first works on the study of toxins of pale toadstool began to be carried out by F. Linen and W. Wieland. In 1937, they were able to obtain the crystalline form of a toxin, which was called phalloidin. After 4 years, scientists isolated a second toxin - amanitine. The harmfulness of these components is evidenced by medical statistics: from 90 to 95% of all deaths occur as a result of poisoning pale toadstool.
In rare cases, a short-term improvement in the condition may occur, but by this time, as a rule, irreversible degenerations of the heart, liver, spleen and kidneys have already occurred in the body. The condition of the patient again sharply worsens, and even at the begun treatment the probability of a fatal outcome can make from 8 up to 30%.
In fungi of the family of fly agaric( pale toadstool and fly-agaric smelly) there is a protein toxin that causes hemolysis - the dissolution of red blood cells. In addition to fly agarics, hemolytic proteins are also found in edible fungi: oyster mushrooms, volvariella, winter fungus and fly-agaric gray-pink. However, it should be emphasized that these toxins in these mushrooms are destroyed already at a temperature of 70 "C, so after frying and frying the mushrooms are completely rendered harmless and they can be eaten."
Currently, doctors are developing new methods for treating poisoning with pale toadstool.are aimed at the normalization of liver function. It is known that homeopaths try to treat similar ones, but used in small doses. From a pale toadstool and fly agaric, a substance of protein nature has been obtained which rendersneutralizing effect on the toxins of these fungi, as well as serums that protect the body from poisoning with fly poisoned mushrooms
In addition to mushrooms from the genus of fly agaric, dangerous toxins contain lines( ordinary and giant), as well as some types of cobwebs and lobes( mushrooms from the genus Helvella).
Effects of string toxins
Lines - special mushrooms In many regions of our country the lines are allowed to billets and sell as conditionally edible mushrooms. After proper treatment, they can be eaten, and usually this does not lead to any serious consequences. At the same time in Germany and some other countries of the West, the sale of lines was banned in the XIX century.after the cases of poisoning with these fungi became more frequent.
The fact is that in the new lines there is a toxin, which is similar in effect to the toxic substances contained in the pale toadstool. It also damages almost all internal organs( liver, kidneys, spleen, heart), destroys red blood cells. The toxin of fungi can be up to 0.5% of the weight of dry mushrooms.
According to medical statistics, poisoning can occur after using not only poisonous, but also conditionally edible fungi. When poisoning neozvevrezhennymi lines appear nausea, vomiting, severe headache, convulsions. A dose of 400 g of dried mushrooms can lead to death.
The toxic substances contained in the lines do not break down even after prolonged boiling. But after a long( at least 5-6 months) drying in the air, poisonous substances are rendered harmless, and they can be used to prepare a wide variety of dishes.
Some mycologists suggest that biosynthesis and the formation of toxic substances depend on the conditions of growth of these fungi. Others believe that a dangerous toxin is formed as a result of the decomposition of proteins in overripe fruit bodies of fungi. Symptoms of poisoning are manifested after 6-10 hours. These include fatigue, headache, jaundice, prolonged vomiting and diarrhea, overcrowding of the stomach, pain in the liver. If severe poisoning can occur, convulsions, delirium, shortness of breath, heart failure and impaired lung function, which can even lead to a fatal outcome.
To prevent this, it is necessary to take timely measures to provide first aid and call a doctor. This poisoning is treated with penicillin, thioctacid and vitamins B6, C, K.
Action of toxins of arachnids
Among the poorly studied is the toxin of orelanin, contained in some types of cobwebs. Studies of this toxin were initiated after the
of how in Poland in the 50's. XX century.more than 100 cases of poisoning with this fungus were recorded, with every sixth leading to death. This type of toxin consists of 2 fractions. Each of them has a high lethality of action, but the character of the impact on the human body, they are very different. The first component of orllanina causes asphyxia and respiratory failure, the second leads to motor paralysis.
The danger of this toxin is manifested in a very long latent period of exposure. By the duration of the course it exceeds the latent period of pale toadstool. Symptoms of spider poisoning sometimes appear only after 2 weeks. During this time, the toxin affects the kidneys, which can also cause death.