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FLY AGARIC (Fungus)

Amanita muscaria

Amanita Family [Amanitaceae]  

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5th Oct 2004, Leeds & Liverpool Canal, Leigh. Photo: © RWD
The psychotropic substances within may affect animals too, which is probably why some animal has half eaten it. The white stem sometimes has a white ring, or skirt part-way up.


20th Aug 2009, Touch Hills, Sterling, Scotland. Photo: © Derek Mayes
The white warts are the remains of the veil.


16th July 2004, Eskdale Valley, Cumbria. Photo: © RWD


5th Oct 2004, Leeds & Liverpool Canal, Leigh. Photo: © RWD


20th Aug 2009, Touch Hills, Sterling, Scotland. Photo: © RWD
The white gills are plainly visible in this bite mark.


5th Oct 2004, Leeds & Liverpool Canal, Leigh. Photo: © Derek Mayes
Close-up of white warts.


Uniquely identifiable characteristics: There is no other mushroom quite like this one.

Distinguishing Feature : The white spots on a red domed top. No relation to : Fly Honeysuckle (Lonicera xylosteum) or to Fly Orchid (Ophrys insectifera). Nor is a there any relation to Spanish Fly (Lytta vesicatoria), an emerald green beetle infamous for its supposed aphrodisiacal properties but is instead a powerful toxin called Cantharidin which has comparable effects to Strychnine. It's aphrodiasiac effects are due merely to intense irritation of the genitals due to internal bleeding!

This mushroom with irregular white scales amidst a domed, scarlet-red top with a satin sheen, although hallucinogenic, is also poisonous and can result in the hospitalization of imbibers. It is the quintessential 'Toadstool' of Fairy Tales and may have given rise to the legend of Father Christmas wearing red and white clothing and appearing to go down chimneys. It should not be eaten!

The white spots and flecks can wash off after heavy rain, as can also the red colouring.

Fly Agaric gets its name from its former use as a preparation for killing flies.

As is usual in both plant and animal kingdoms, red usually signifies a warning of danger. These warnings are not for altruistic reasons, but rather for selfish reasons: the plant or animal does not want to be destroyed. The red warnings are not universal. The much more dangerously poisonous Destroying Angel and Death Cap mushrooms are white. Beware!

All four of these compounds are found in the Fly Agaric mushroom. Note the chemical similarity between them. Muscarine, or Muscarin was the first to be found in Amanita Muscaria, from where it derived its name, but is present only in trace amounts. Muscarine mimics some of the effects of the neurotransmitter acetylcholine, but not all. It is a non-hallucinogenic poison that can cause salivation, sweating and tears in the eyes, which can be followed by stomach pain, nausea, diarrhoea, blurred vision and difficulty with breathing. Death by cardiac arrest is rare. Atropine is the antidote to muscarine poisoning. Muscarine has a much greater presence in the poisonous inocybe family of mushrooms, particularly Red-Staining Inocybe.

Ibotenic Acid is a powerful neurotoxin with applications in medical research as a brain-lessioning agent. When ingested, ibotenic acid is converted into muscimol within the body.

Muscimol is derived from Ibotenic Acid within Fly Agaric and other members of the amanita family of mushrooms by a process that removes the carboxylic acid radical, COOH. It is a potent GABA (gamma aminobutyric acid) agoniser. Both Ibotenic Acid and Muscimol are psychoactive substances, with Muscarine up to ten times more potent than its progenitor. Unlike Muscarine which cannot cross the blood brain barrier on account of its' positive electrical charge, Muscimol does and affects the hippocampus, cerebral cortex and cerebellum. It is hallucinogenic and may result in in-coordination, loss of balance and muscle twitching.

Muscazone is another poisonous psychoactive substance. Note that it is an amino acid, albeit not one normally present in mammals. It is a 'non-protein coding amino acid' (NPAA or non-proteinogenic amino acid), of which there are more than 500 known in the natural world. NPAAs, because they resemble normal protein-coding amino acids, can be mistaken by the body for the normal amino acids, the result of which is the equivalent of a spanner in the works.

The proportion of all these noxious substances can vary, some specimens of Fly Agaric may be relatively innocuous, whilst others may be positively deleterious to health.

CHROMO ALKALOIDS / BETAILAIN PIGMENTS

  Muscaflavin is one of a number of Betalains, which are a group pf Chromo Alkaloids, meaning that they are highly coloured alkaloids. Muscaflavin, along with Muscapurpurine and Muscaaurine are responsible for the redness of the cap. Note that it has a seven-membered ring, with a nitrogen atom incorporated into the ring. Muscaflavin is an orange coloured betalain pigment.

  Muscaaaurine is a violet coloured betalain. Note that both Muscauurine and Muscapurpurin below have both lost the seven-membered ring of Muscaflavine, replaced by one of six.

  Whilst the colour of Muscaaurine is violet. Together, all three Betalains contribute to the red colour of the cap. In common with many brightly coloured compounds, there are many double-bonds in the molecules. Containing two or more carboxylic acid groups, all three are acids. The upper ring system contains a lactone moiety.

VANADIUM ORGANOMETALLICS

  Two proposed structures for Amavadin, both now thought to be incorrect.


  Amavadin is quite unusual in that it contains an atom of vanadium, shown in red (left structure only). At the centre is an 8-coordinated vanadium VI atom. As can be seen, the ligands form a symmetrical dimer containing two seven-membered rings. It is found in three species of Amanita Mushroom, two of which are non-native to the UK. Its function within Amanita mushrooms is unknown, but it may help repair damaged tissue via the release of hydrogen peroxide, H2O2. It is toxic.

Fly Agaric accumulates Vanadium, concentrating it to between 35 to 350ppm (dry weight). Amavadin may make a very interesting catalyst for use in organic chemistry. In solution it is pale blue. It may find use for treating some forms of diabetes, for Vanadium complexes such as this mimic the effects of insulin. Although an electrically neutral molecule it has four separated charges caused by the negative charges on the ring of four oxygen atoms which encircle the vanadium atom, which should really only have two bonds. The Vanadium atom has a coordination number of eight in this compound. The mushroom may use Amavadin as a toxin to protect it from herbivores, but this seems not to be very effective judging by the number of bite marks to be found (from herbivores perhaps more interested in the hallucinogenic properties of some of the other components).

The structure of Amavadin was so hard to determine that it was once thought to contain two five-membered rings, as shown in the schematic top right, which even has three oxygen atoms more let alone a large disparity in the number of carbon and hydrogen atoms (but it does have the correct number of vanadium atoms: one!)


  But it seems that the former discredited structure at top right may have been more correct than other structure shown top left. It now seems that the correct structure is as shown alongside, which does indeed possess 5-membered rings (but four rather than two, and no 7-membered rings). This structure still possesses an 8-coordinated vanadium (shown in light blue in the centre), but it has a charge of +2, and forms salts with metals such as calcium. Because the salts crystallize more readily this enabled X-ray crystallography to get a better handle on the structure. In common with the top left diagram the planar ring of four oxygen atoms depicted in red are still present, as are the four methyl groups, but there are now ten atoms of oxygen and the -OH groups are banished. The two ligands are based upon di-methylated versions of N-hydroxyimino-2,2'-dipropionic acid. The N-O moieties are upper and lower sides of the plane of the vanadium atom with four oxygen atoms. The whole caboodle has bilateral symmetry.


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FLY AGARIC (Fungus)

Amanita muscaria

Amanita Family [Amanitaceae]  

family8Amanita family8Amanitaceae genus8amanita