Warning on False or True Morels and Button Mushrooms with Potential Toxicity Linked to Hydrazinic Toxins: An Update

Abstract

Recently, consumption of the gyromitrin-containing neurotoxic mushroom Gyromitra sp. (false morel), as gourmet food was hypothesized to play a role in sporadic amyotrophic lateral sclerosis genesis. The present review analyses recent data on edibility and toxicity of false and true morels and Agaricus spp. Controversy about the toxic status of Gyromitra esculenta was due to variable toxin susceptibility within consumers. We suggest that Verpa bohemica, another false morel, is also inedible. We found a temporary neurological syndrome (NS) with cerebellar signs associated with high consumption of fresh or dried true morels Morchella sp. After ingestion of crude or poorly cooked fresh or dried morels, a gastrointestinal “haemolytic” syndrome was also observed. Agaritine, a water soluble hydrazinic toxin closely related to gyromitrin is present along with metabolites including diazonium ions and free radicals, in Agaricus spp. and A. bisporus, the button mushroom, and in mice after ingestion. It is a potential weak carcinogen in mice, but although no data are available for humans, a lifetime low cumulative extra cancer risk in humans can be estimated to be about 10−5. To conclude, a safety measure is to avoid consuming any true morels or button mushrooms when crude or poorly cooked, fresh or dried.

Benzothiazolyl and Benzoxazolyl Hydrazones Function as Zinc Metallochaperones to Reactivate Mutant p53

“…38 They are found in toxic mushrooms and even in some common button mushrooms. 39 Not all hydrazines are toxic, and many are approved drugs like carbidopa for Parkinson's disease, isoniazid against malaria, and phenelzine sulfate for depression. Nevertheless, the hydrolytic stability of our hydrazones is still a safety concern.…”

“…Many hydrazines are known to be toxic . They are found in toxic mushrooms and even in some common button mushrooms . Not all hydrazines are toxic, and many are approved drugs like carbidopa for Parkinson’s disease, isoniazid against malaria, and phenelzine sulfate for depression.…”

Nodding syndrome: A key role for sources of nutrition?

“…Agaritine is catalyzed in rat and mouse kidney homogenates by removal of the glutamyl group to yield reactive free hydrazine [ 54 , 55 ] which, after formylation to its corresponding hydrazone, may be activated both in vitro and in vivo to a methylating intermediate resulting in the formation of O 6 -methyl-(O 6 -mG) and N7-methylguanines (N7-mG) in DNA [ [56] , [57] , [58] ]. Additionally, 4-hydroxymethyl) benzenediazonium salt, a carcinogen in A. bisporus , generates a carbon-centered radical, the 4-(hydroxymethyl)phenyl radical, which causes DNA strand breaks [ 59 ].…”

Role of Hydrazine-Related Chemicals in Cancer and Neurodegenerative Disease

“…Novel hydrazides have been isolated from Streptomyces spp., and S. purpeofuscus synthesizes negamycin ([2-(3,6-diamino-5-hydroxyhexanoyl)-1-methylhydrazino]­acetic acid). The commonly eaten cultivated mushroom, Agaricus bisporus , contains the phenylhydrazine agaritine, β- N -[γ- l ­(+)-glutamyl]-4-hydroxymethylphenylhydrazine (C 12 H 17 N 3 O 4 ) and 4-hydroxymethylphenylhydrazine (C 7 H 10 N 2 O). , Much higher concentrations of agaritine than those found in commercial samples of A. bisporus (200–500 mg/kg fresh weight) can occur in wild species of this genus, the highest of which (10,000 mg/kg fresh weight) was found in A. elvensis ( syn. A. cappellianus Hlaváček) .…”