The fat pholiota, Pholiota adiposa (Batsch) P. Kumm.
Agaricus adiposus Batsch,
Elench. fung. cont. prim. (Halle): 147 (1786)
Dryophila adiposa (Batsch) Quél.
Enchir. fung. (Paris): 68 (1886)
Hypodendrum adiposum (Batsch) Overh.
Cap: 4-10 cm diameter, hemispherical with involute margin when young, expanding to convex, finally flattened with deflexed margin, with or without blunt umbo, not hygrophanous, not transculently striate, yellow-brown, with yellow to sulphur yellow marginal zone, entirely covered with apressed to uplifted, reddish to blackish brown, gelatinous squamules, particularly at center, in moist condition usually strongly slimy to glutinous, but slime easily washed off in rainy weather; when young with large velar flocks, especially at margin.
Gills: moderately crowded to crowded, broadly adnate, sometimes emarginate or with decurrent tooth, thin, subventricose, up to 10 mm broad, pale lemon-yellow at first, through ochre-brown to reddish brown with slight olivaceous tinge, with entire, concolorous edge.
Stem: 2-5 cm long x 0.5-1.0 cm diameter, centrally or slightly eccentrically inserted, tapering towards common base, solid then fistullose, when young with well-developed, thick, fibrillose-floccose annulus, above annulus pale yellow, orange to reddish brown below, glabrous above annulus, squamulose with dark reddish to blackish brown, gelatinous squamules below, glabrous above annulus.
Odor: indistinct, according to Bas et al. However, some older research has suggested that odor may be used as a defining characteristic for this species (Badcock, 1939).
Spore print: dark reddish brown.
Spores: 5-6.5 x 3-4 µm, smooth, ellipsoid, nonamyloid, amygdaliform. Further details on spore characteristics may be found in Batko (1946).
Habitat: found on living and dead stems of Fagus sylvatica, usually low on the stem or on roots and trunks; late summer to autumn; infrequent or rare.
Description adapted largely from Bas et al., pg. 84-5
Methanol extracts of P. adiposa fruit bodies were shown to inhibit the enzyme β-hydroxy-β-methyl glutaryl coenzyme a reductase (HMG-CoA reductase), a rate-limiting enzyme in cholesterol biosynthesis, by 55.8%. Solvent extraction and column chromatography were used to obtain a purified product, identified as stigmasterol, that had an IC50 of 6.8 µg (Yu et al., 2007).
The nutritive value of protein from the fruitbodies and the cultured mycelia of P. adiposa has been evaluated (Hui et al., 2004). Proteins from cultured mycelia had a higher nutritive value than from the fruitbodies, based on the following quantitative characteristics of protein quality:
- amino acid score 82.86
- chemical score 54.96
- essential amino acid index 92.73
- biological value 89.38
- nutritional index 35.42
- score of ratio coefficient of amino acid 87.24
The authors conclude that the submerged cultivated mycelium of P. adiposa could be considered a good source of protein.
Spiroaxanes are sesquiterpenes with a spiro[1,5]decane ring system; the canonical spiroaxane is shown below. These compounds have been isolated from a variety of marine sponges. Recently, a novel spiroaxane (15-hydroxy-6α,12-epoxy-7β, 10α H,11βH-spiroax-4-ene) was isolated from the culture broth of P. adiposa (Liu et al., 2008).
A variety of compounds have been isolated and purified from P. adiposa using column chromatography and and variety of spectroscopic techniques, including:
- 1-(N,N,N-trimethyl ethyl amino phosphoryl)-2,3-dilinolein ion
- glyceryl phosphate
Polysaccharides extracted from the mycelial culture of P. adiposa and administered intraperitoneally into white mice at a dosage of 300 mg/kg inhibited the growth of Sarcoma 180 and Ehrlich solid cancers by 70% and 60%, respectively (Ohtsuka et al., 1973).
The antitumor potential of P. adiposa was later corroborated in a Korean study using an antitumor screening test involving Sarcoma 180 cells transplanted into mice. Mice which were injected with a million Sarcoma 180 cells, and then one day later injected with the alcohol-precipitated polysaccharides from a hot-water extract of the fat Pholiota (at a dose of 20 mg/kg body weight per day for 10 days) had an inhibition ratio of 27.3%, compared to the mice that didn’t get the mushroom extract (Chung et al., 1982). Furthermore, it has been shown that treatment of Sarcoma 180 tumor-bearing mice with P. adiposa polysaccharides resulted in decreased tumor weights, increased carbon particle clearance and phagocytic indices, and significantly higher serum levels of TNF-α and IL-2, compared with untreated controls. The authors suggest that the anti-tumor activity of P. adiposa polysaccharide is related to immune system enhancement (Zhao et al., 2007)
The 60% methanolic extract of Pholiota adiposa exhibited antimicrobial activity, shown by using both the disc-diffusion and broth dilution methods (Dulger et al., 2004). Specifically, the extract (at 25 mg/ml) inhibited the growth of Bacillus subtilis (17.0/7.0/1.25), Escherichia coli (19.0/28.2/0.625), Klebsiella pneumonia (11.8/22.4/5.0), Staphylococcus aureus (18.6/19.8/1.25), Streptococcus pyogenes (11.0/18.0/2.5), and Mycobacteria smegmatis (20.4/16.0/0.625); the three numbers in parentheses indicate the zone of inhibition (mm), the zone of inhibition of the control antibiotic Gentamicin at 2 mg/ml, and the minimum inhibitory concentration (mg/ml).
Angiotensin I-converting enzyme (ACE) inhibitors have shown utility in relieving or preventing hypertension. P. adiposa was shown to inhibit angiotensin I-converting enzyme (ACE) (Izawa et al., 2006). Also, an ACE inhibitor, identified as a novel pentapeptide (amino acid sequence Gly-Glu-Gly-Gly-Pro) was isolated from the fruiting body of Pholiotoa adiposa. Maximal ACE inhibitory activity (IC50; 0.25 mg) was obtained with a protracted warm water extraction (30°C for 12h); after extensive purification, this activity increased to an IC50 of 0.044 mg (Koo et al., 2006).
Researchers used a combination of the herb Lycii fructus and P. adiposa to produce a traditional Korean rice wine with antihypertensive properties (Kim et al., 2006). The addition of 1% L. fructus and 0.1% P. adiposa fruiting bodies into the mash prior to fermentation produced a wine which had an antihypertensive ACE inhibitory activity of 82%.
Investigating the effect of a P. adiposa extract on fat mass in hyperlipidemic mice on a high-fat diet, one study concluded this mushroom may have potential for use as a functional food that can act as a prophylactic against hyperlipidemia. Although the extracts did not cause any significant change in the total triglyceride contents nor the epididymal fat mass, the retroperitoneal fat decreased significantly decreased in mice on the high-fat diet (Cho et al., 2006). Excessive retroperitoneal fat mass is typical in males with upper-body obesity (Arner, 1997).
A presentation from the fourth International Medicinal Mushroom Conference discusses the antioxidative properties of superoxide dismutase from P. adiposa.
Regional adipocity in man.
J Endocrinol. 1997 155:191-2
Biometrical researches of secondary spores and a study of the mycelium of Pholiota adiposa Fr., P. heteroclita Fr., P. mutabilis (Schaeff.) FT., P. spectabilis Fr., and P. squarrosa (Mull.) Fr.
Trans. Brit, mycol. Soc. 1946 29(4):242-9.
Chung KS, Choi EC, Kim BK, Kim YS, Park YK.
The constituents and culture of Korean Basidiomycetes anti tumor poly saccharides from the cultured mycelia of some basidiomycetes.
Arch Pharm Res. 1982 5(1):17-20.
Kim JH, Lee DH, Choi SY, Park JS, Lee JS.
Effects of Lycii fructus and edible mushroom, Pholiota adiposa, on the quality and angiotensin I-converting enzyme inhibitory activity of Korean traditional rice wine.
Food Biotechnol. 2006 20(2):183-91.
Koo KC, Lee DH, Kim JH, Yu HE, Park JS, Lee JS.
Production and characterization of antihypertensive angiotensin I-converting enzyme inhibitor from Pholiota adiposa.
J Microbiol Biotechnol. 2006 16(5):757-63.
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.
Shimizu K, Fujita R, Kondo R, Sakai K, Kaneko S.
Morphological features and dietary functional components in fruit bodies of two strains of Pholiota adiposa grown on artificial beds.
J Wood Sci. 2003 49(2):193-6.
Yu HE, Lee DH, Seo GS, Cho SM, Lee JS.
Characterization of a novel β-hydroxy-β-methyl glutaryl coenzyme a reductase-inhibitor from the mushroom, Pholiota adiposa.
Biotechnol Bioproc Eng. 2007 12:618-24.