Agaricus subrufescens (syn. Agaricus blazei, Agaricus brasiliensis or Agaricus rufotegulis) is a species of mushroom, commonly known as almond mushroom, almond agaricus, mushroom of the sun, God's mushroom, mushroom of life, royal sun agaricus, jisongrong, or himematsutake (Chinese: 姬松茸, Japanese: 姫まつたけ, "princess matsutake"). A. subrufescens is edible, with a somewhat sweet taste and a fragrance of almonds.

Agaricus subrufescens
Agaricus subrufescens
Agaricus subrufescens
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Agaricaceae
Genus: Agaricus
Species:
A. subrufescens
Binomial name
Agaricus subrufescens
Peck (1893)
Synonyms
Agaricus subrufescens
View the Mycomorphbox template that generates the following list
Gills on hymenium
Cap is convex
Hymenium is free
Stipe has a ring
Spore print is brown
Ecology is saprotrophic
Edibility is choice

Taxonomy

edit

Agaricus subrufescens was first described by the American botanist Charles Horton Peck in 1893.[1] During the late nineteenth and early twentieth centuries, it was cultivated for the table in the eastern United States.[2] It was discovered again in Brazil during the 1970s, and misidentified as Agaricus blazei Murrill, a species originally described from Florida. It was soon marketed for its purported medicinal properties under various names, including ABM (for Agaricus blazei Murrill), cogumelo do sol (mushroom of the sun), cogumelo de Deus (mushroom of God), cogumelo de vida (mushroom of life), himematsutake, royal sun agaricus, Mandelpilz, and almond mushroom.

In 2002, Didukh and Wasser correctly rejected the name A. blazei for this species, but unfortunately called the Brazilian fungus A. brasiliensis,[3] a name that had already been used for a different species, Agaricus brasiliensis Fr. (1830). Richard Kerrigan undertook genetic and interfertility testing on several fungal strains,[2] and showed that samples of the Brazilian strains called A. blazei and A. brasiliensis were genetically similar to, and interfertile with, North American populations of Agaricus subrufescens. These tests also found European samples called A. rufotegulis to be of the same species. Because A. subrufescens is the oldest name, it has taxonomical priority.

Description

edit
 
The floccose stipe and annulus of A. subrufescens

Initially, the cap is hemispherical, later becoming convex, with a diameter of 5 to 18 centimetres (2 to 7 inches).[4] The cap surface is covered with silk-like fibers, although in maturity it develops small scales (squamulose). The color of the cap may range from white to grayish or dull reddish brown; the cap margin typically splits with age. The flesh of A. subrufescens is white, and has the taste of "green nuts", with the odor of almonds.[4] The gills are not attached to the stalk (free), narrow, and crowded closely together. They start out whitish in color, then later pinkish, and finally black-brown as the spores mature. Spores are ellipsoid, smooth, dark purplish-brown when viewed microscopically, with dimensions of 6–7.5 by 4–5 μm. The stipe is 6 to 15 cm (2+12 to 6 in) by 1 to 1.5 cm (38 to 58 in) thick, and bulbous at the base. Initially solid, the stipe becomes hollow with age; it is cottony (floccose) to scaly toward the base.[4] The annulus is abundant and double-layered; it is bent downward toward the stem, smooth and whitish on the upper side, and covered with cottony scales on the lower side.

A type of ergostane-type compounds called blazeispirols have been isolated from A. subrufescens.[5]

Distribution and habitat

edit

A. subrufescens forms fruit bodies singly or in clusters in leaf litter in rich soil, often in domestic habitats.[6] Originally described from the northeastern U.S. and Canada, it has been found growing in California, Hawaii, Great Britain, the Netherlands, Taiwan, Philippines, Iran,[7] Australia, Brazil,[2] and Uruguay.[8]

Toxicity

edit

Preliminary research indicates Agaricus products may have toxic effects on liver function marked by increased serum level of liver enzymes, especially in people with ovarian cancer,[9][10] and may cause allergic reactions.[9] The U.S. Food and Drug Administration has issued warning letters to companies marketing Agaricus supplement products with unproven health claims of providing benefits to the immune system.[11][12]

Uses

edit

A. subrufescens is edible, with a somewhat sweet taste and an almond aroma resulting from benzaldehyde, benzyl alcohol, benzonitrile, and methyl benzoate.[13]

Used in traditional and alternative medicine for its supposed anti-cancer effects, Agaricus mushrooms have not been assessed by sufficient high-quality clinical research to define safety and biological properties upon consumption as a food, dietary supplement, or drug.[9]

See also

edit

References

edit
  1. ^ Peck CH (1893). "Report of the Botanist (1892)". Annual Report on the New York State Museum of Natural History. 46: 85–149.
  2. ^ a b c Kerrigan, RW (2005). "Agaricus subrufescens, a cultivated edible and medicinal mushroom, and its synonyms". Mycologia. 97 (1): 12–24. doi:10.3852/mycologia.97.1.12. PMID 16389952.
  3. ^ Wasser, Solomon P.; Didukh, Marina Ya.; de Amazonas, Maria Angela L.; Nevo, Eviatar; Stamets, Paul; da Eira, Augusto F. (2002). "Is a Widely Cultivated Culinary-Medicinal Royal Sun Agaricus (the Himematsutake Mushroom) Indeed Agaricus blazei Murrill?". International Journal of Medicinal Mushrooms. 4 (4): 267–290. doi:10.1615/intjmedmushr.v4.i4.10. OCLC 39977461.
  4. ^ a b c Murrill, W. A. (1922). "Dark-Spored Agarics: III. Agaricus". Mycologia. 14 (4): 200–221. doi:10.2307/3753642. JSTOR 3753642.
  5. ^ Hirotani, M; Sai, K; Hirotani, S; Yoshikawa, T (2002). "Blazeispirols B, C, E and F, des-A-ergostane-type compounds, from the cultured mycelia of the fungus Agaricus blazei". Phytochemistry. 59 (5): 571–7. Bibcode:2002PChem..59..571H. doi:10.1016/s0031-9422(01)00445-9. PMID 11853754.
  6. ^ Smith, Alexander Hanchett (1975). A Field Guide to Western Mushrooms. Ann Arbor, Mich: University of Michigan Press. p. 228. ISBN 978-0-472-85599-5.[page needed]
  7. ^ Asef M.R. (2020). Field guide of Mushrooms of Iran. Tehran: Iran-Shanasi Press. p. 360. ISBN 9786008351429.
  8. ^ Sequeira, Alejandro. Hongos.
  9. ^ a b c "Agaricus". Memorial Sloan Kettering Cancer Center. 2018. Retrieved 21 November 2018.
  10. ^ Sweet, E. S.; Standish, L. J.; Goff, B.; Andersen, M. R. (2013). "Adverse events associated with complementary and alternative medicine use in ovarian cancer patients". Integrative Cancer Therapies. 12 (6): 508–516. doi:10.1177/1534735413485815. PMC 4613776. PMID 23625025.
  11. ^ Ronald Pace (15 July 2014). "Warning letter: C P Health Products Inc". Inspections, Compliance, Enforcement, and Criminal Investigations, US Food and Drug Administration. Retrieved 21 November 2018.
  12. ^ LaTonya M. Mitchell (8 August 2014). "Warning letter: EnerHealth Botanicals, LLC". Inspections, Compliance, Enforcement, and Criminal Investigations, US Food and Drug Administration. Retrieved 21 November 2018.
  13. ^ Chen, CHU-CHIN; Wu, Chung-MAY (1984). "Volatile Components of Mushroom (Agaricus subrufecens)". Journal of Food Science. 49 (4): 1208–1209. doi:10.1111/j.1365-2621.1984.tb10433.x.