Shrooms
Check out this great post by our resident chemistry professor, Siromi Samarasinghe
It reminds me, there was an interesting study using fMRI on volunteers tripping on mushrooms. It is surprising that activity in the brain was lower while on mushrooms. However, I disagree with the article, that just because the results are counter to what was expected, it doesn’t automatically make the results correct. It does make the results un-biased; I agree with that part. The next step should use more quantitative imaging, like PET.
Originally shared by Siromi Samarasinghe
The Good the Bad and the Ugly – the chemical diversity of mushrooms
The world of mushrooms is as complex as the human world. They too have their Good, the Bad and the Ugly. What makes them so? The chemical composition of the mushrooms play a big role in determining their nature.
Gourmet’s delight and Therapeutic mushrooms
✿ Shitake mushrooms (Lentinus edodes, Lentinela edodes) are widely used in East Asian cuisine. These meaty morsels are savoured by the gourmet. Many mouth watering recipes bring forth their culinary flavour.
Sun drying is reported to bring out the umami or savoury flavour of this mushroom. http://goo.gl/8W8bsn
✿ Shitake mushrooms are known to contain the compound Eritadinine which has been isolated from them and characterised. Eritadinine is reported to lower high blood cholesterol levels. http://goo.gl/Cxsg4C
✿ A novel protein designated as lentin, with potent antifungal activity was also isolated from Shitake mushrooms. Lentin is reported to have inhibitory effects on the activity of HIV-1 reverse transcriptase and proliferation of leukemia cells.
✿ An accumulating body of evidence suggests that consumption of dietary mushrooms can protect against breast cancer. In a study carried out in 2010, scientists tested and compared the ability of five commonly consumed mushrooms to modulate cell number balance in the cancer process using MCF-7 human breast cancer cells. The tested mushrooms were: maitake ( Grifola frondosa), crimini (Agaricus bisporus), portabella (Agaricus bisporus), oyster (Pleurotus ostreatus) and white button (Agaricus bisporus). The study suggests that both common and specialty mushrooms may be chemoprotective against breast cancer. http://goo.gl/uhX3Jz
Magic mushrooms (Psychoactive mushrooms)
Intentional or accidental ingestion of these mushrooms which contain hallucinogenic components could be a tragedy to the consumer.
✿ Psilocybin and psilocin are the principal components in ‘magic mushrooms’ which belong to the genus Psilocybe.
Psilocybin is chemically related to the amino acid tryptophan and is structurally similar to the neurotransmitter serotonin.
Psilocybin is a member of the general class of tryptophan-based compounds that originally functioned as antioxidants in earlier life forms before assuming more complex functions in multicellular organisms, including humans.
Biosynthetically, the biochemical transformation from tryptophan to psilocybin involves several enzyme reactions.
✿ In addition to psilocybin and psilocin, studies have clarified psychoactive mushrooms to produce psychoactive agents such as ibotenic acid, and muscimol. However, the status of psychoactive mushrooms in most countries, as illegal hallucinogens, has prevented full investigation of their biochemical properties. Recent studies have shown that many psychoactive agents pass through the blood-brain barrier and act on neurotransmitter receptors.
It has also been shown that psilocybin and psilocin have high therapeutic efficiency for obsessive-compulsive disorder which is a difficult-to-treat nervous disease.
The toxic mushrooms – Lethal beauties, Death caps and Destroying Angels
✿The poisonous substances in mushrooms are generally known as
mycotoxins since mushrooms are fungi.
✿Some of the known toxic compounds in mushrooms are :
Alpha amanitin (deadly: causes liver damage) – principal toxin in genus Amanita. (E.g. Death cap (Amanita phalloides), Destroying angel). The measure of lethality of amanitin (oral LD50 value) is approximately 0.1 mg/kg
Phallotoxin (causes gastrointestinal upset) – also found in poisonous Amanitas
Orellanine (deadly: causes kidney failure) – principal toxin in genus Cortinarius.
Muscarine (sometimes deadly: can cause respiratory failure) – found in genus Omphalotus.
Gyromitrin (deadly: causes neurotoxicity, gastrointestinal upset, and destruction of blood cells) – principal toxin in genus Gyromitra.
Coprine (causes illness when consumed with alcohol) – principal toxin in genus Coprinus.
Ibotenic acid (causes neurotoxicity) and muscimol (hallucinogenic) – principal toxins in A. muscaria, A. pantherina, and A. gemmata.
The Good, the Bad and the Ugly of the Mushroom world continue to be a challenge to scientists, with their diverse chemical compositions, at the same time offering culinary flavours, hallucinogens and medicines to humans.
Read more: http://goo.gl/65LXJ9
Related post: Much information on mushrooms has been shared from time to time on Science Sunday. http://goo.gl/6ddgLn
Photo: Amanita muscaria
Photo credit: Buddhini Samarasinghe
(I meant to share this on Buddhini Samarasinghe ‘s birthday but got caught up on ‘birthday activities’! Better late than never!)
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October 16, 2013
The OCD study did not show efficacy. There was little effect of drug found. But it was a small, poorly designed study, so more work is needed. http://www.ncbi.nlm.nih.gov/m/pubmed/17196053/
October 16, 2013
I agree Matthew Baggott. Thanks for the link.
October 19, 2013
Amanita Muscaria is a very interesting specimen – its effects on humans are very idiosyncratic. A nurse in Haida Gwaii / Queen Charlotte Islands related to me (many years ago), what she’d observed – out of four ingesters, two had a great time, one got bupkis, and one got violently ill.
October 19, 2013
David Archer I think Peter Lindelauf has some knowledge of those.
October 20, 2013
Sounds like like good advice Peter Lindelauf