Rubroboletus satanas is a Basidiomycota fungus of the Boletaceae family that has a thick margin cap that can exceed 30 cm in diameter. The stem is fleshy, thick and of a very intense red color with red reticules. The pores, for their part, are initially yellowish and later acquire an orange tint.
This species was located until a few years ago within the genus Boletus. However, recent studies showed that this genus was polyphyletic, which is why new genera, such as Rubroboletus, were created or some in disuse were resurrected to relocate about two-thirds of the species it contained.
Rubroboletus satanas. Taken and edited from: H. Krisp.
The species of the genus are characterized by presenting a cap with a reddish surface, yellow tubes in the hymenium, red-orange or blood-red pores, a reticulated red stipe, and their flesh changes color when cut.
Reproduction
The basidioma, or fruiting body, is the body responsible for producing spores in Basidiomycota fungi. The basidium is a microscopic reproductive structure that will generally produce four haploid spores, or basidiospores, by meiosis.
The basidiospores germinate and produce a septate mycelium, with a single nucleus between septa. This mycelium can eventually meet other compatible mycelium and they will fuse producing a dicariont mycelium, that is, with two haploid nuclei per compartment.
This mycelium will grow by mitotic cell divisions that allow both nuclei in each compartment to divide simultaneously. When the conditions are right, the basidiome or fruiting body develops and emerges.
In the ventral part of the hat is the hymenium, which in this species is made up of tubes that open to the outside through pores. Also in this area are the basidia. In each basidium, the two haploid nuclei undergo karyogamy and a diploid zygote is formed that subsequently undergoes meiosis and produces four haploid basidiospores.
This occurs in the distal part of short projections of the basidia called sterigmata. When the spores mature, they go out into the medium through the pores and the fruiting body disintegrates, but the dicarion mycelium persists.
Nutrition
Rubroboletus satanas is a heterotrophic species, that is, it needs to feed on organic matter already made and not decomposing. In order to better access the nutrients it requires for its vital processes, this species establishes mutualistic relationships with different species of plants.
These relationships are called ectomycorrhizae. The species with which Rubroboletus satanas can establish this type of relationship are mainly oak and chestnut trees. The fungus develops a kind of hyphal mantle that surrounds the root of its host.
This mantle will prevent the colonization of the root by other fungi and will connect to a hyphal network that develops towards the interior of the root, growing between (and not within) the epidermal and cortical cells of the same.. This network, called the Hartig network, will surround each cell.
The function of the Hartig network is to allow the exchange of water, nutrients and other substances in a bidirectional way between the fungus and the plant. In this way, the fungus provides the plant with water and minerals for its food and receives in return already prepared organic nutrients, mainly carbohydrates.
Toxicity and effects
Rubroboletus satanas has been referred to as the Boletus sensu lato species with the highest toxicity, and its name or specific epithet refers to that "malignancy" of the mushroom. The effects of ingesting this species, however, are rarely fatal and its toxicity is lost if the fungus is consumed after careful cooking.
Rubroboletus satanas. Taken and edited from: photo taken by Archenzo in an Italian wood Piacenza's Appennino.
Poisoning from the ingestion of this species of mushroom is not frequent, mainly due to its low densities and because the species can be confused with other mushrooms such as Rubroboletus rhodoxanthus or R. pulchrotinctus, which are also toxic, but not with edible species.
In domestic animals the occurrence of poisoning by ingestion of Rubroboletus satanas is apparently more frequent, but the effects of poisoning in them are similar to those presented in humans and are not fatal either.
Owners of small animals can confuse this type of poisoning with infections of viral or bacterial origin and even with problems caused by changes in diet.
Bolesatina
Rubroboletus satanas toxicity is due to a glycoprotein called bolesatin. Scientists have isolated this substance in the fruiting bodies of the species. The fact that it is a protein explains why the toxic effect of the mushroom decreases or disappears after cooking, since the temperature causes denaturation of these molecules.
Researchers have shown in laboratory tests that bolesatin in vitro inhibits protein synthesis in the cell. It also has mitogenic properties, that is, it acts during the cell cycle by stimulating cell division.
Effects edit
Bolesatin causes fungal gastrointestinal syndrome, which causes inflammation of the digestive tract that causes severe pain, diarrhea, vomiting, and seizures. Sometimes headaches, circulatory disorders and cramps can also occur.
The first symptoms of poisoning appear within 20 minutes of ingestion and generally do not last more than four hours. Cooking causes denaturation of the bolesanthin, so the fungus loses its toxicity.
Treatment
There is no specific treatment for poisoning by ingestion of Rubroboletus satanas, applying only supportive treatments. Doctors do not need to administer emetics because bolesatin has these same effects, so they sometimes have to administer antiemetics instead.
The most important thing is to prevent dehydration of the patient, as well as to correct possible alterations in electrolytes. Some doctors suggest oral administration of activated carbon as this compound can adsorb most toxins.
References
- J. Patocka (2018). Bolesatine, a toxic protein from the mushroom, Rubroboletus satanas. Military Medical Science Letters.
- B. Puschner (2013). Mushrooms. In Small Animal Toxicology. 3 rd Edition. Elsevier.
- Rubroboletus. On Wikipedia. Recovered from en.wikipedia.org
- Rubroboletus satanas. On Wikipedia. Recovered from en.wikipedia.org
- Boletus satanas. Recovered from basketdecestas.com
- C. Lyre. Ectomycorrhizae and endomycorrhizae. Recovered from lifeder.com
- K. Zhao, G. Wu & ZL Yang (2014). A new genus, Rubroboletus, to accommodate Boletus sinicus and its allies. Phytotaxa.