Pleurocybella

Pleurocybella
Pleurocybella porrigens
Scientific classification
Kingdom: Fungi
Division: Basidiomycota
Class: Basidiomycetes
Order: Agaricales
Family: Marasmiaceae
Genus: Pleurocybella
Singer (1947)
Type species
Pleurocybella porrigens
(Pers. ex Fr.) Singer (1947)[1]

Pleurocybella is a genus of fungus in the Marasmiaceae family. The genus is monotypic, containing the single species Pleurocybella porrigens, widespread in temperate forests of the Northern Hemisphere.[2] P. porrigens, known as the angel wing, is a white-rot wood-decay fungus on conifer wood, particularly hemlock (genus Tsuga).[3] The flesh is thin and fragile compared to the oyster mushrooms (Pleurotus ssp.).

Pleurocybella porrigens has historically been generally regarded as edible[3][4] but this has been brought in to question by recent deaths apparently associated with P. porrigens consumption.

Synonyms for Pleurocybella porrigens include Pleurotus porrigens, Phyllotus porrigens, Dendrosarcus porrigens, Pleurotellus porrigens, and Nothopanus porrigens.

Contents

Toxicity

Although P. porrigens is generally regarded as edible,[3][4] as of 2011, it has been implicated in two documented outbreaks involving fatal encephalopathy. Both incidents were in Japan, and most victims had pre-existing kidney disorders.[5][6][7]

The first incident occurred in September and October 2004[8] across nine prefectures in Japan, and involved the sickening of 59 people and the eventual death of 17.[5] Most of those who died had pre-existing liver problems, and the average age of those effected was 70.[5] Death occurred between 13 and 29 days after the onset of symptoms, and the onset of symptoms occurred at most three weeks after consumption of P. porrigens.[8]

The second incident occurred in 2009, when a 65 year old man who had been on hemodialysis died from acute encephalopathy after eating P. porrigens.[5]

The mechanism of action for the toxicity of P. porrigens has not been definitively established,[5] but several possibilities have been suggested. It has been demonstrated that P. porrigens contains an unusual unstable amino acid which is toxic to the brain cells of rats in cell culture studies,[5][9] but it has not yet been possible to definitively determine that this was the cause of the fatal encephalopathies.[5] Other mechanisms have been suggested for P. porrigens apparent toxicity, including the possibility that cyanide levels in P. porrigens may be high enough to be toxic.[10]

See also

References

  1. ^ Singer, R. (1947). "New genera of fungi. III.". Mycologia 39 (1): 77–89. doi:10.2307/3755289. JSTOR 3755289. PMID 20283546. 
  2. ^ Kirk PM, Cannon PF, Minter DW, Stalpers JA. (2008). Dictionary of the Fungi (10th ed.). Wallingford, UK: CABI. p. 548. ISBN 978-0-85199-826-8. 
  3. ^ a b c Trudell, S.; Ammirati, J. (2009). Mushrooms of the Pacific Northwest. Timber Press Field Guides. Portland, Oregon: Timber Press. p. 137. ISBN 0-88192-935-2. 
  4. ^ a b Arora, David (1986). Mushrooms Demystified (2nd ed.). Berkeley, CA: Ten Speed Press. p. 135. ISBN 0898151694. 
  5. ^ a b c d e f g Michael W. Beug. "Pleurocybella porrigens toxin unmasked?". McIlvainea, Journal of American Amateur Mycology. http://www.namyco.org/publications/mcilvainea/v20/pleurocybella_toxin.html. Retrieved June 1, 2011. 
  6. ^ Saviuc, Philippe; Danel, Vincent (2006). "New Syndromes in Mushroom Poisoning". Toxicological Reviews 25 (3): 199–209. doi:10.2165/00139709-200625030-00004. PMID 17192123. 
  7. ^ Fumitake Gejyo, Noriyuki Homma, Noboru Higuchi, Ken Ataka, Tomoko Teramura, Bassam Alchi, Yukio Suzuki, Schinichi Nishi and Ichiei Narita (2005). "A novel type of encephalopathy associated with mushroom Sugihiratake ingestion in patients with chronic kidney diseases". Kidney International 68: 188–192. doi:10.1111/j.1523-1755.2005.00393.x. 
  8. ^ a b Kato, T.; Kawanami, T.; Shimizu, H.; Kurokawa, K.; Sato, H.; Nakajima, K.; Nomoto, T.; Seta, T. et al. (2004). "An outbreak of encephalopathy after eating autumn mushroom (Sugihiratake; Pleurocybella porrigens) in patients with renal failure: A clinical analysis of ten cases in Yamagata, Japan". No to shinkei = Brain and nerve 56 (12): 999–1007. PMID 15729876.  edit
  9. ^ Wakimoto, T.; Asakawa, T.; Akahoshi, S.; Suzuki, T.; Nagai, K.; Kawagishi, H.; Kan, T. (2011). "Proof of the Existence of an Unstable Amino Acid: Pleurocybellaziridine in Pleurocybella porrigens". Angewandte Chemie International Edition 50 (5): 1168–1170. doi:10.1002/anie.201004646.  edit
  10. ^ Hiroshi, Akiyama; Toida Toshihko, Sakai Shinobu, Amakura Yoshiaki, Kondo Kazunari, Sugita-Konishi Yoshiko, Maitani Tamio,. "Determination of Cyanide and Thiocyanate in Sugihiratake Mushroom Using HPLC Method with Fluorometric Detection" (PDF). JOURNAL OF HEALTH SCIENCE -TOKYO 52 (1): 73–77. http://jhs.pharm.or.jp/data/52%281%29/52_073.pdf. Retrieved 2011-06-02. 

External links