Medicinal Mushrooms

Tricholoma portentosum (Fr.) Quel., the dingy agaric.
   Source: Wikipedia Commons.

Agaricus portentosus Fr.
  Syst. mycol. (Lundae) 1: 39 (1821)
Melanoleuca portentosa (Fr.) Murrill
  N. Amer. Fl. (New York) 10(1): 23 (1914)

Dingy agaric
Glanzinde ridderzwam (Dutch)
Shimofurishimeji (Japanese)
Viiruvalmuska (Finnish)
Petit gris d'automne, Tricholome prétentieux, Bise d'automne, Verdoyant (French)
Grauer Ritterling, Russiggestreifter Ritterling, Schwarzgestreifter Ritterling (German)
Tricoloma portentoso (Italian)
Gråmusserong (Norwegian)
Ryadovka seraya (Russian)
Streckmusseron (Swedish)

Cap: 5-11 cm diameter, convex to bell-shaped, expanding to plano-convex with or without low, broad umbo or with slight central depression, with involute then straight, finally sometimes reflexed, irregularly lobed margin; color dark grey-brown to blackish sepia at center, towards margin paler lead-grey, yellow-grey, greenish-yellow to almost white at outermost margin, often with slight purple tinge, viscid when moist, irregularly fibrillose upon drying.
Gills: moderately crowded, adnate-emarginate, up to 15 mm broad, often transvenose, white then in part turning lemon- to sulphur yellow with entire, concolorous or slightly darker edge.
Stem: 3.5-12 tall x 1-3 cm thick, cylindrical, attenuated towards base or subclavate, often with yellow tinges in lower part when old, innately fibrillose, shining, often slightly pruinose at apex, coarsely fibrillose to subtomentose below.
Context: white in stipe, grayish in cap; farinaceous.
Smell: farinaceous after cutting.
Taste: mild, farinaceous.
Spores: 6.0-7.5 x 3.5-4.5 µm, ellipsoid to oblong.
Habitat: in groups, in coniferous or mixed forests.
Edibility: edible.

Description adapted from Van Crevel et al., 1988, pp. 116. This reference also explains that a number of variants have been described for this species, including:

• Tricholoma portentosum var. boutevillei M. Bon - darker, squamulose cap, grows with Quercus and Fagus trees
• Tricholoma portentosum var. lugdunense M. Bon - pale fruitbody
• Tricholoma portentosum var. album Jacquet. & Bon - white fruitbody

The dietary fiber content was determined to be ~ 45% (dry weight); protein content was ~ 16% (dry weight); essential amino acids accounted for 61.8% total amino acid contents, with  leucine, isoleucine and tryptophan being the limiting amino acids. The corrected amino acid scores (PDCAAS) of T. portentosum was low compared to casein, egg white and beef, but higher than that of many vegetable proteins. The fat content was 5.7% (dry weight), with oleic and linoleic acids accounting for more than 75% of total fatty acids (Diez and Alvarez, 2001).

In a separate study (Barros et al., 2007a), the values for various chemical and nutritional parameters are listed below (expressed as g/100 g fresh weight, or % by weight if you prefer) :

   moisture - 93.05±0.51
   total oil content - 0.38±0.02
   crude protein - 2.12±0.08
   ash - 0.81±0.03
   carbohydrates - 3.64±0.16

Also, the energy value of 100 g (fresh weight) was 26.46±1.14 kcal.

A number of sterols have been isolated and identified from the fruit bodies of T. portentosum (Yaoita et al., 1999):

   5α,6α,8α,9α-diepoxy-(22E,24R)-ergost-22-ene-3β,7α-diol
   5α,6α-epoxy-(22E,24R)-ergosta-8,22-diene-3β,7β-diol
   5α,6α-epoxy-(22E,24R)-ergosta-8,22-diene-3b,7α-diol
   5α,6α-epoxy-(22E,24R)-ergosta-8(14),22-diene-3β,7α-diol
   (22E,24R)-ergosta-7,22-diene-3β,5α,6β,9α-tetrol
   (22E,24R)-ergosta-7,22-diene-3β,5α,6α,9α-tetrol
   (22E,24R)-ergosta-7,22-diene-3β,5α,6β-triol
   (24S)-ergost-7-ene-3β,5a ,6β-triol (12)
   3β,5α,9α-trihydroxy-(22E,24R)-ergosta-7,22-dien-6-one
   3β,5α,9α,14α-tetrahydroxy-(22E,24R)-ergosta-7,22-dien-6-one
   5α,8α-epidioxy-(22E,24R)-ergosta-6,22-dien-3β-ol

Medicinal properties
Antitumor effects

An extract of the fruit bodies inhibited the growth of Sarcoma 180 and Ehrlich solid cancers in mice by 70% and 60%, respectively (Ohtsuka et al., 1973).

The total phenolic content of T. portentosum (in mg/g) was determined to be 6.57±0.31 in the cap, 3.91±0.17 in the stem, and 10.80±0.47 in the entire fruitbody. In the entire fruit body, this total included 0.40 mg/g flavonoids and 0.52 mg/g ascorbic acid (Barros et al., 2007a).

The antioxidant properties of T. portentosum have been evaluated (Ferreira et al., 2007a). Methanolic extracts from the entire mushroom, the cap and the stipe, separately, were screened for their reducing power and free radical scavenging capacity by chemical assays. The methanolic extract (at a concentration of 50 mg/ml) was shown to have excellent reducing power compared to the positive controls BHA and α-tocopherol. Specifically, expressed as an EC₅₀ (mg/ml), the reducing power was 3.12, 3.69, and 4.82 for the entire fruit body, the cap, and the stem, respectively.  In terms of free radical scavenging activity (FRSA), methanolic extracts from T. portentosum were only moderate in activity (22.9, 40.2 and >50% for the entire fruit body, the cap, and the stem, respectively).

A DMSO extract of T. portentosum was tested for its antibiotic activity against various bacteria. The extract was effective only against Gram+ bacteria (Bacillus cereus, B. subtilis) as well as the fungus Cryptococcus neoformans (causative agent of cryptococcosis) (Barros et al., 2007b).

Links

There's a photo gallery at BioPix.

References

Barros L, Baptista P, Correia DM, Casal S, Oliveira B, Ferreira ICFR.
Fatty acid and sugar compositions, and nutritional value of five wild edible mushrooms from Northeast Portugal.
Food Chem. 2007a 105(1):140-5.

Barros L, Calhelha RC, Vaz JA, Ferreira ICFR, Baptista P, Estevinho LM.
Antimicrobial activity and bioactive compounds of Portuguese wild edible mushrooms methanolic extracts.
Euro Food Res Technol. 2007b 225(2):151-6.

Diez VA, Alvarez A.
Compositional and nutritional studies on two wild edible mushrooms from northwest Spain.
Food Chem. 2001 75(4):417-22.

Ferreira ICFR, Baptista P, Vilas-Boas M, Barros L.
Free-radical scavenging capacity and reducing power of wild edible mushrooms from northeast Portugal: Individual cap and stipe activity.
Food Chem. 2007 100(4):1511-6.

Karosene SA.
Vitamin content in hymenomycetous fungi part 6. Thiamine and riboflavin in the fruiting bodies of Tricholoma portentosum.
Lietuvos TSR Mokslu Akademijos Darbai Serija C Biologijos Mokslai. 1975 3:147-54.

Ohtsuka S, Ueno S, Yoshikumi C, Hirose F, Ohmura Y, Wada T, Fujii T, Takahashi E.
Polysaccharides having an anticarcinogenic effect and a method of producing them from species of Basidiomycetes.
UK Patent 1331513, 26 September 1973.

Pourrat H, Regerat F, Carnat AP.
Study of the oil extracted from fruit bodies of Tricholoma portentosum.
Annales Pharmaceutiques Francaises. 1976 34(11-1):453-6.

Regerat F, Pourrat H, Pourrat A.
Ergosterol and portensterol occurrence in mycelial cultures of Tricholoma portentosum and Rhodopaxillus nudus.
Annales Pharmaceutiques Francaises. 1976 34(9-10):383-5.

Regerat F, Pourrat H.
New sterol isolation portensterol from fruitbodies of Tricholoma portentosum, Rhodopaxillus nudus and Clitocybe nebularis.
Annales Pharmaceutiques Francaises. 1976 34(7/8):323-8.

Van Crevel R, Bas C, van Os J. (1988).
Flora Agaricina Neerlandica: Critical monographs on families of agarics and boleti occurring in the Netherlands. Vol 4. (Bas C, TH Kuyper, ME Noordeloos,  EC Vellinga,  Eds.).
Taylor and Francis: Rotterdam.

Yaoita Y, Endo M, Tani Y, Machida K, Amemiya K, Furumura K, Kikuchi M.
Studies on the constituents of mushrooms, part VI - Sterol constituents from seven mushrooms.
Chem Pharm Bull. 1999 47(6):847-51.

Last modified: 01-Apr-2008

Lactarius acris (Bolton) Gray
   Source: Wikipedia Commons
   Credit: James Lindsey's Ecology of Commanster Site

Synonyms

Agaricus acris Bolton
Agaricus lactifluus [var.] acris (Bolton) Pers.
Lactifluus acris (Bolton) Roussel
Lactifluus acris (Bolton) Kuntze

Cap: 3-9 cm diameter, convex-depressed, expanding to broadly vase-shaped, often with a broad obtuse umbo, finally irregularly infundibuloform; surface slimy in wet weather and very shiny, when dry dull and pruinose-velvety; color dark chestnut-brown to gray-brown, mostly with a very slight olive tone, becoming paler tobacco-brown, date brown, or olive-leather brown, when young often with numerous ivory colored or pinkish buff spots, in age also at times entirely ochraceous-brownish to pallid leather-yellowish.
Latex: white, copious in young specimens, quickly changing to bright coral red, later bright orange, fading to rosy white in drying, very acrid on the tongue and lips, and in the throat intensely burning.
Context: rigid, fragile-firm, pithy in the stipe, red when injured, acrid to burning but not as much as the latex, odor unpleasant.
Gills: very crowded, adnate becoming decurrent, thickish, scarcely forked, fairly narrow (3-5 mm), tapered to cap margin, at first ivory white then ochraceous, as seen from the edges with a flesh reddish tint, in age pruinose from the spores, when injured staining red to whitish droplets of latex along the edges.

    Source: Wikipedia Commons
    Credit: James Lindsey's Ecology of Commanster Site

Stem: 3-8 cm long, 5-15 mm thick, cylindrical or narrowed downward, rarely enlarged downward, often somewhat eccentric, usually curved, smooth to slightly wrinkled, seldom longitudinally striate, the entire length delicately, the entire length delicately pruinose, later naked, dry, solid, stuffed; cortex 1 mm thick, at first pure white, later pallid buff or pale buff toned olive-gray, red to reddish when injured.
Spore print: bright ocher (pale cream according to Gardezi and Ayub, 2003).
Spores: 7.5-9 x 7.5-8.5 µm (5.5-6.5 x 3.2-6 µm says Gardezi and Ayub, 2003), with narrow warts, most of the surface reticulate with heavy amyloid bands.
Habitat: grows on calcium-rich soil, July to November, under beech especially, Europe. Has been reported in Pakistan (Gardezi and Ayub, 2003). As yet not known from North America.
Edibility: inedible.

Medicinal properties
Anti-tumor effects

An extract of L. acris fruit bodies inhibited the growth of Sarcoma 180 and Ehrlich solid cancers in mice by 100% (Ohtsuka et al., 1973).

There's some nice pictures at Funghi Teramaini.

References

Gardezi SRA, Ayub N.
Mushroom of Kashmir VI.
Asian J Plant Sci. 2003 2(10):804-10.
PDF available from ANSI journals

Ohtsuka S, Ueno S, Yoshikumi C, Hirose F, Ohmura Y, Wada T, Fujii T, Takahashi E.
Polysaccharides having an anticarcinogenic effect and a method of producing them from species of Basidiomycetes.
UK Patent 1331513, 26 September 1973.

Smith AH, Hesler LR.
Studies on lactarius-III the North American species of section Plinthogali.
Brittonia. 1962 14(4):369-440.
JSTOR preview

Last modified: 30-Mar-2008

Agaricus aequivocus (Holmsk.) E.H.L. Kraus
Agaricus multiplex Dill.
Boletus acanthoides Bull.
Boletus giganteus Pers.
Caloporus acanthoides (Bull.) Quél.
Cladomeris acanthoides (Bull.) Quél.
Cladomeris giganteus (Pers.) Quél.
Clavaria aequivoca Holmsk.
Flabellopilus giganteus (Pers.) Kotl. & Pouzar
Grifola acanthoides (Bull.) Pilát
Grifola gigantea (Pers.) Pilát
Grifola lentifrondosa Murrill
Meripilus lentifrondosus (Murrill) M.J. Larsen & Lombard [as 'lentifrondosa']
Merisma acanthoides (Bull.) Gillet
Merisma giganteum (Pers.) Gillet
Polypilus frondosus var. intybaceus (Fr.) Bondartsev
Polypilus giganteus (Pers.) Donk
Polyporus acanthoides (Bull.) Fr.
Polyporus acanthoides Rostk.
Polyporus aequivocus (Holmsk.) E.H.L. Krause
Polyporus frondosus Fr.
Polyporus giganteus (Pers.) Fr.
Polyporus lentifrondosus (Murrill) Murrill

The basidiomycete Meripilus giganteus occurs in the living trees of several genera, and causes a white rot of the butt and roots.

Fruiting body: annual; 50-80 cm diameter, pileate with fan-shaped to spathulate caps originating from a common base; aggregates of caps can be up to 1 m in diameter and 70 kg fresh weight; individual caps 10-30 cm diameter, 1-2 cm thick; upper cap surface cream white to yellow-brown, zonate; pore surface cream to yellow-orange-brown pores (3 to 5 per mm), rapidly turning blackish when bruised or cut.
Spores: 5.5-6.5 x 4-5 µm, subglobose, hyaline.
Edibility: edible, but with a sour taste and fibrous texture, palatability is questionable; younger, more tender specimens are to be preferred.
Habit and Habitat: on stumps of freshly felled trees and at the base of standing strees; often apparently growing from the ground, but always in contact with wood; circumboreal in the northern hemisphere, usually found on hardwoods, particularly horse chestnut (Aesculus), beech (Fagus), lime (Tilia) and oak (Quercus).

Medicinal properties
Immunosuppressive effects

In the methanolic extract of Meripilus giganteus a mixture of saturated and unsaturated fatty acids (among them palmitic, oleic and linoleic acid) and ergosterol peroxide were identified as immunosuppressive components. Furthermore, a homologous series of straight-chained saturated hydrocarbons with 22 to 26 and 29 to 32 C-atoms were identified (Narbe et al.,1991). However, when tested for immunosuppressive activity, various extracts of this mushroom were not active in the assay system used (Koch et al., 2002). In these experiments, the assay was based on the ability of the extract to inhibit the binding of endotoxin to CD14⁺ cells and to influence LPS-induced release of proinflammatory cytokines (IL-1β, IL-6, TNF-α), regulatory cytokines (IL-2, IL-4, IL-10, IFN-γ), and the release of reactive oxygen species; these are physiological responses consistent with hypersensitivity reactions, like asthma.

A crude methanol extract from this species was shown to have significant cytotoxic activity against murine cancer cell line 3LL (Lewis lung carcinoma), with an IC₅₀ of 19.8 ±2.6 µg/ml (Tomasi et al., 2004).

Links

Mushroom Expert
Learn more about the Giant polypore's life history here and here.
BioPix has a nice gallery of photos.

References

Bhavanandan VP, Lindberg B, Bouveng HO.
Polysaccharides from Polyporus giganteus.
Acta Chemica Scandinavica. 1964 18(2):504-12.

Koch J, Witt S, Lindequist U.
The influence of selected higher Basidiomycetes on the binding of lipopolysaccharide to CD14⁺ cells and on the release of cytokines.
Int J Med Mush. 2002 4(3):229-35.

Larsen MJ, Lombard FF.
The status of Meripilus giganteus (Aphyllophorales, polyporaceae) in North America.
Mycologia. 1988 80(5):612-21.

Narbe G, Lindequist U, Teuscher E.
Immunosuppressive activities of Meripilus giganteus (Pers Fr) Karst.
Pharmazie. 1990 45(8):637-8.

Narbe G, Lindequist U, Teuscher E, Franke P, Vainiotalo P, Basner R.
Studies of the chemistry of immunosuppressive active fractions from Meripilus giganteus (Pers ex Fr.) Karst.
Pharmazie. 1991 46(10):738-40.
Pubmed

Tomasi S, Lohezic-Le Devehat F, Sauleau P, Bezivin C, Boustie J.
Cytotoxic activity of methanol extracts from Basidiomycete mushrooms on murine cancer cell lines.
Pharmazie. 2004 59(4):290-3.
Pubmed

Last updated: 29-Mar-2008

The inky cap, Coprinopsis atramentaria, growing on a stump in Elk Island National Park, near Edmonton, Canada.
Photo credit: © Robert Sasata.

Synonyms

Agaricus atramentarius Bull.
Agaricus fimetarius sensu Sowerby (1799)
Agaricus luridus Bolton
Agaricus plicatus Pers.
Agaricus sobolifer Hoffmann
Coprinus atramentarius (Bull.) Fr.
Coprinus atramentarius var. soboliferus (Fr.) Rea
Coprinus luridus (Bolton) Fr.
Coprinus plicatus (Pers.) Gray
Coprinus sobolifer Fr.

Inky cap
Tippler's bane

Cap: 2-8 cm diameter, grey to greyish-brown; oval then campanulate or conical; fibrillose; radially grooved almost to disc; margin irregularly notched and lobed, splitting when the cap expands.
Flesh: thin, greyish.
Gills: free, initially white, then black and deliquescing; up to 1 cm broad, cottony on the edge, crowded.
Stem: 10-15 cm long, 8-15 mm thick; equal; silky white to very light brown, with small upward pointing scales below the ring; readily separates from cap.
Spore print: black.
Spores: smooth, ellipsoid, 8-12 x 4.5-6.5 µm.
Habitat and distribution: grows in caespitose clusters or gregariously in fields and gardens, in rich soils or around stumps. Common in the Northern Hemisphere; has been reported in South Africa (Reid and Eicker, 1999).
Edibility: edible with caution - poisonous if consumed with alcohol.

Research has shown that, when grown on a compost bed, this mushroom required a cold shock (in this case, a temperature reduction from 25°C to 20°C) to initiate the formation of fruiting bodies (Stott and Broderick, 1995).

Bioactive compounds

The poisonous effects of C. atramentaria are caused by a molecule named coprine, or N5-1-hydroxycyclopropyl-L-glutamine (shown below), which is metabolized to 1-aminocyclopropanol. This latter compound then inhibits the enzyme alcohol dehydrogenase, which normally oxidizes alcohol (i.e., ethanol) into acetaldehyde, indicated by the reaction below:

     CH₃CH₂OH + NAD⁺ → CH₃CHO + NADH + H⁺

After alcohol intake under the influence of coprine, the concentration of acetaldehyde in the blood may be 5 to 10 times higher than that found during metabolism of the same amount of alcohol alone. As acetaldehyde is one of the major causes of the symptoms of a "hangover" this produces immediate and severe negative reaction to alcohol intake. Some 5-10 minutes after alcohol intake, the unfortunate victim may experience the effects of a severe hangover for a period of 30 minutes up to several hours. Symptoms include flushing of the skin, accelerated heart rate, shortness of breath, nausea, and vomiting. The ill effects of coprine may be felt if alcohol is consumed for up to several days after eating the mushroom. The biochemical mechanism of action of coprine and the resultant symptoms are similar to the drug disulfiram, used to treat chronic alcoholism (Tottmar and Lindberg, 1977; Carlsson et al., 1978).

Coprine, ADH-inhibiting metabolite from C. atramentaria.

Coprine was shown to cause testicular lesions in mice and dogs (Jönsson et al., 1979), adding another note of caution to those wishing to consume it.

Medicinal properties
Anti-tumor

Extracts from the fruit bodies of C. atramentarius inhibited the growth of Sarcoma 180 and Ehrlich solid cancers by 100% (Ohtsuka et al., 1973).

The aqueous extract of Tippler's bane was shown to reduce the mycelial growth and inhibit sporulation of Penicillium expansum, a pathogenic mold (Florianowicz, 2000).

References

Carlsson, A, Henning, M, Lindberg, P, Martinson, P, Trolin, G, Waldeck, B, Wickberg, B.
Disulfiram-like effect of coprine, pharmacologically active principle of Coprinus atramentarius.
Acta Pharmacologica Et Toxicologica. 1978 42(4):292-7.
Pubmed

Florianowicz T.
Inhibition of growth and sporulation of Penicillium expansum by extracts of selected basidiomycetes.
Acta Societatis Botanicorum Poloniae. 2000 69(4):263-7.

Hatfield GM, Schaumberg JP.
Isolation and structural studies of coprine, disulfiram-like constituent of Coprinus atramentarius.
Lloydia-the Journal of Natural Products. 1975 38(6):489-96.
Pubmed

Jonsson M, Lindquist NG, Ploen L, Ekvarn S, Kronevi T.
Testicular lesions of coprine and benzcoprine.
Toxicology. 1979 12(2):89-100.
Pubmed

Lee IK, Jeong CY, Cho SM, Yun BS, Kim YS, Yu SH, Koshino H, Yoo ID.
Illudins C-2 and C-3, new illudin C derivatives from Coprinus atramentarius ASI20013.
J Antibiotics. 1996 49(8):821-2.
Pubmed

Lindberg, P, Bergman, R, Wickberg, B.
Isolation and structure of coprine, a novel physiologically active cyclopropanone derivative from Coprinus atramentarius and its synthesis via 1-aminocyclopropanol.
J Chem Soc-Chem Comm. 1975 (23):946-7.

Lindberg, P, Bergman, R, Wickberg, B.
Isolation and structure of coprine, in vivo aldehyde dehydrogenase inhibitor in Coprinus atramentarius - syntheses of coprine and related cyclopropanone derivatives.
J Chem Soc-Perk Trans 1. 1977 (6):684-91.
Pubmed

Michelot, D.
Poisoning by Coprinus atramentarius.
Nat Toxins. 1992 1(2):73-80. Review.

Mohamed SH, Dix NJ.
Resource utilization and distribution of Coprinus comatus, Coprinus atramentarius, Lacrimaria velutina and Melanoleuca grammopodia.
Transactions of the British Mycological Society. 1988 90:255-63.

Ohtsuka S, Ueno S, Yoshikumi C, Hirose F, Ohmura Y, Wada T, Fujii T, Takahashi E.
Polysaccharides having an anticarcinogenic effect and a method of producing them from species of Basidiomycetes.
UK Patent 1331513, 26 September 1973.

Reid DA, Eicker A.
South African fungi 10: New species, new records and some new observations.
Mycotaxon. 1999 73:169-97.

Stott K, Broderick A.
Improved fruiting of Coprinus atramentarius using cold-shock treatment during growth.
World J Microbiol Biotechnol. 1995 11(6):693-4.

Tottmar O, Lindberg P.
Effects on rat-liver acetaldehyde dehydrogenases in vitro and in vivo by coprine, disulfiram-like constituent of Coprinus atramentarius.
Acta Pharmacologica Et Toxicologica. 1977 40(4):476-81.

Last modified: 28-Mar-2008

Looking like a charred, disembodied hand from an old B-movie, it's Xylaria polymorpha (Pers.) Grev.
Picture credit: Chris Evans, River to River CWMA, Bugwood.org
Source: www.forestryimages.org

Synonyms

Coelorhopalon obovatum (Berk.) Overeem
Hypoxylon polymorphum (Pers.) Mont.
Penzigia obovata (Berk.) Speg.
Sphaeria obovata Berk.
Sphaeria polymorpha Pers.
Xylaria corrugata Har. & Pat.
Xylaria obovata (Berk.) Berk.
Xylaria rugosa Sacc., (1906)
Xylosphaera obovata (Berk.) Dennis
Xylosphaera polymorpha (Pers.) Dumort.

Basionym

Sphaeria polymorpha Pers. 1797

Common name

In Indian traditional medicine (Ayurvedic medicine), the powdered fruit bodies, mixed in equal proportion with sugar, is used to promote lactation after birth (Rai et al., 1993).

This fungus is responsible for root rot, and the leaves of afflicted trees dry out and drop prematurely.  According to the Canadian Forest Service website's page, X. polymorpha is one of the few ascomycete species capable of decomposing the wood of sugar maple and box elder.

Fruit body: 3-8 cm tall, 1-3 cm wide, irregularly club-shaped (fingerlike), often knobby or gnarled, white to grayish and powdery initially (during the asexual stage), then black with a finely wrinkled or roughened or cracked surface.
Flesh: tough, white. The perithecia (spore-producing cavities) are just below the surface crust. The asci are 200 x 10 µm.
Spores: the ascospores are dark-brown to blackish, fusiform, smooth, 20-30 x 5-10 µm; the conidia are smaller, elongated or elliptical, smooth, and hyaline.
Habitat: gregarious on stumps and fallen timber of deciduous trees, including Acer rubrum, Coffea arabica, Platanus acerifolia and Shorea robusta (Sivanesan and Holliday, 1998). Season all year. Common. Because of the toughness of the species, the fruiting bodies can persist for a long time. In fact, one early paper (Barnes, 1940) reported finding a 16-year old specimen living on a piece of elm wood.
Edibility: Inedible.
Distribution: America and Europe.

From Cooke MC. 1871. Handbook of British Fungi: With Full Descriptions of all the species, and Illustrations of all the Genera. Vol 2. London: Macmillan and Co. pg. 789. The full text of this old classic is available for viewing in Google Books.

Bioactive compounds

2-Hexylidene-3-methylsuccinic acid, aka piliformic acid, is the major metabolite produced by X. polymorpha (Anderson et al., 1985).

This compound (shown above), which was later isolated from the marine fungus Halorosellinia oceanica BCC 5149, showed moderate cytotoxicity against KB and BC-1 cell lines (Chinworrungsee et al., 2001).

Dead man's fingers was shown to contain about 6% mannitol (dry weight), a sugar used as a diuretic agent (Snatzke and Wolff, 1987). Other compounds include 4-(3'-Acetyl-2',6'-dihydroxy-5'-methylphenyl)- 4-hydroxy- 2-methoxybutanoic acid (globoscinic acid) and 5-(3'-acetyl-2',6'-dihydroxy- 5'-methylphenyl)-3-methoxy- 2,3,4,5-terahydrofuran-2-one (globoscin) (Adeboya et al., 1995), and two cytotoxic cytochalasins 19,20-epoxycytochalasin Q and its deacetyl analog (Dagne et al., 1994). Of the latter two compounds, both were shown to be cytotoxic, but inactive in an HIV-protease inhibitory assay and a mechanism-based DNA damaging yeast assay.

Research has also gone into determining the optimal conditions for the production of X. polymorpha polysaccharides grown in liquid culture (Yang and Huaan, 2004).

Two new polypropionates designated as xylarinic acids A (4,6,8-trimethyl- 2,4-decadienoic acid) and B (2,4,6-trimethyl- 2-octenoic acid) were isolated from X. polymorpha fruiting bodies.  Both compounds displayed significant antifungal activity against the pathogenic plant fungi Pythium ultinum, Magnaporthe grisea, Aspergillus niger, Alternaria panax, and Fusarium oxysporium, but they did not show any antibacterial nor cytotoxic effects (Jang et al., 2007).

Tom Volk's fungus of the month, April 2000
Mushroom Expert
More pictures and description here at the Fungi on Wood pages
Another informative page from the Penn State New Kensington Virtual Nature Trail

References

Abate D, Abraham WR, Meyer H.
Cytochalasins and phytotoxins from the fungus Xylaria obovata.
Phytochem. 1997 44(8):1443-8.

Adeboya M, Edwards RL, Laessoe T, Maitland DJ, Whalley ASJ.
Metabolites of the higher fungi .28. Globoscinic acid and globoscin, a labile acid-lactone system from Xylaria globosa and Xylaria obovata.
J Chem Soc-Perk Trans. 1995 1(16):2067-72.
Abstract - RSC Publishing

Anderson JR, Edwards RL, Whalley AJS.
Metabolites of the higher fungi. 22. 2-butyl-3-methylsuccinic acid and 2-hexylidene-3-methylsuccinic acid from Xylariaceous fungi.
J Chem Soc Perk Trans I. 1985 7:1481-6.

Barnes B.
A note on longevity in Xylaria.
Trans Brit Mycol Soc. 1940 24(3/4):356.

Chinworrungsee M, Kittakoop P, Isaka M, Rungrod A, Tanticharoen M, Thebtaranonth Y.
Antimalarial halorosellinic acid from the marine fungus Halorosellinia oceanica.
Bioorg Med Chem Lett. 2001 11(15):1965-9.
Pubmed

Dagne E, Gunatilaka AAL, Asmellash S, Abate D, Kingston DGI, Hofmann GA, Johnson RK.
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Last modified: 24-Mar-2008