Trametes gibbosa: The Ultimate Mushroom Guide

About The Trametes gibbosa Mushroom

Trametes gibbosa is a polypore mushroom that causes a white rot. It is found on beech stumps and the deadwood of other hardwood species.

Fruit bodies are 8–15 cm in diameter and semicircular.

The upper surface is usually gray or white, but maybe greenish in older specimens due to algal growth. Elongated pores are located on the under-surface. The fruiting bodies are frequently attacked by boring beetle larvae.

Other names: Beech Bracket, Lumpy Bracket, Outkovka hrbatá (Czech), Puklet Læderporesvamp (Danish), Witte bultzwam (Dutch), Tramète bossue (French), Gebuckelte Tramete/Buckeltramete (German), Púpos egyrétűtapló (Hungarian), Bøkekjuke (Norwegian), Wrośniak garbaty (Polish), Траметес Горбатый (Russian), Trúdnikovec hrbatý (Slovakian), Grbasta ploskocevka (Slovenian), Korkticka (Swedish).

Trametes gibbosa Identification

1. Cap

   Annual basidiomata, bracketed, semicircular, imbricate, and measuring from 5 to 20 cm of length, per 1-4 cm of thickness; pileus surface grooved, zoned, villous, tuberculate, later becoming glabrous; of ochraceous-cream color, green due to algal presence; obtuse and rounded edge.

2. Hymenium

   White-cream pores, with elongated pores, often sinuous, 1 to 5 mm long and up to 1 mm broad; the tubules are whitish, mono or pluri-stratified.

3. Flesh

   The context is thicker close to the substratum, up to 3 cm, coriaceous and fibrous, azoned, of white-cream color.

4. Habitat

   Annual species; it grows all year round on trunks and dead stumps of broad-leaved trees, especially of beech.

5. Microscopy

   Trimitic hyphal structure with hyaline, fibulate and ramified generative hyphae, the connective hyphae have many ramifications, very numerous are also the skeletal hyphae, without septa; cystidia and cystidioles are absent; basidia are tetrasporic cylindrical or cylindrical-clavate, hyaline, with basal clamp connections, 15-20 × 4-6 µm; slender sterigmata; the basidiospores are hyaline, smooth, cylindrical or oblong and bent, inamylod, 4-5 × 1,8-2,3 µm.

Trametes gibbosa Medicinal Properties

Antiinflammatory/vasoprotective activity

Research has shown that polysaccharides isolated from the fruit bodies of T. gibbosa can confer a protective effect to rat blood vessels in the carrageenan assay, suggesting their possible use in pathological disease conditions leading to endothelial damage (Czarnecki and Grzybek, 1995). Carrageenans are a family of linear sulphated polysaccharides from seaweed that, when injected into the pleural cavity of various animals, cause an inflammatory reaction.

The study demonstrated that intravenous administration of T. gibbosa polysaccharides neutralized changes in blood vessel permeability, decreased total protein levels in the pleural effusion, increased the number of neutrophils and eosinophils while reducing the number of lymphocytes in the surrounding blood.

Antitumor activity

Polysaccharides extracted from the mycelial culture of T. gibbosa and administered intraperitoneally into white mice at a dosage of 300 mg/kg inhibited the growth of Sarcoma 180 and Ehrlich solid cancers by 80% and 90%, respectively (Ohtsuka et al., 1973).

The petroleum ether and ethyl acetate extract of T. gibbosa were shown to be cytotoxic to human cervix epitheloid carcinoma cell lines (Hela) and human hepatoma cell lines (SMMC-7721) using the MTT-dye assay. The methanol extract, however, showed weak activity when compared with the flavonoid quercetin (Ren et al., 2006).

Recently, it was shown that organic extracts of T. gibbosum (as Daedalea gibbosa) mycelium are effective in inhibiting the growth of K562 cells, a laboratory model of human chronic myelogenous leukemia (Yassin et al., 2008).

Antiviral effects

Methanol extracts from T. gibbosa were shown to have mild inhibitory effects (i.e., <40% inhibition) on HIV-1 reverse transcriptase activity in vitro (Mlinarič et al., 2005).

Trametes gibbosa Similar Species

1. Trametes hirsuta

   Lloyd 1924, which however has roundish and smaller pores, thin context, pileus surface much velvety to the touch, and more elongated spores.

2. Trametes suaveolens

   Fries 1838, which may be similar to coloration but having, however, great and rounded pores, and the flesh emitting a good smell of anise, clearly bigger spores.

3. Trametes betulina

   Fries 1838 and Lenzites warnieri Durieu & Montagne 1860, similar to pileus appearance but with greyer or brown-ochraceous colors, and having, furthermore, gilled hymenium.

Trametes gibbosa Synonyms

Merulius gibbosus Persoon, 1795 (basionym); Daedalea gibbosa (Persoon) Persoon, 1801; Lenzites gibbosa (Persoon) Hemmi, 1939; Polyporus gibbosus (Persoon) P. Kummer, 1871; PseudoTrametes gibbosa (Persoon) Bondartsev & Singer, 1944.

Trametes gibbosa Taxonomy & Etymology

Originally described by Christiaan Hendrick Persoon in 1796 at which time it was given the binomial scientific name Merulius gibbosus, the Lumpy Bracket obtained its current scientific name in 1836 when it was described and renamed by the Swedish mycologist Elias Magnus Fries.

Synonyms of Trametes gibbosa include Merulius gibbosus Pers., Agarico-suber scalptum Paulet, Daedalea virescens (Lázaro Ibiza) Sacc. & Trotter, Daedalea gibbosa (Pers.) Pers., Polyporus gibbosus (Pers.) P. Kumm., Trametes gibbosa f. tenuis Pilát, and PseudoTrametes gibbosa (Pers.) Bondartsev & Singer.

Trametes, the genus name, comes from the prefix tram- meaning thin - hence the implication is that fruitbodies of fungi in this genus are thin in section. The specific epithet gibbosa means humped or rounded.

The young pinkish specimens shown on the left are growing on a mossy Beech Stump in the New Forest, Hampshire, England; one of the older common names for this polypore fungus is the Beech Bracket.