Trametes gibbosa

Description
Mushroom Identification
Medicinal Properties
Trametes gibbosa Similar Species
History
Synonyms

Description

Trametes gibbosa is a polypore mushroom that causes white rot. The upper surface is usually gray or white but may be greenish in older specimens due to algal growth. Elongated pores are located on the under-surface.

It is found on hardwood, fallen trunks, and stumps, with a preference for beech. It has also been observed on hazelnut trees, Laburnum, Ulmus, Populus, hornbeams, and maple. It is widely distributed throughout Europe.

The combination of three features makes identification unmistakable: the bumpy hump at the point where it attaches to the wood, its almost never rounded pores, which appear elongated and form an irregular, sometimes even lamellar pattern, and the green coloring of its slightly felty upper side that appears sooner or later and is caused by algae growth.

Trametes gibbosa is often inhabited by insect larvae, whose activity shows up in the form of crumbly granules in the immediate vicinity.

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

Mushroom Identification

Fruit Bodies

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.
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.
Flesh

The flesh is dense, crusty, hard, whitish, sometimes yellowish.
Spores

4-5 * 2-2.5 μm, cylindrical, depressed on one side, elongated at the base, colorless..
Spore Print

Whitish.
Habitat

It grows from Summer to Autumn, on dry and fallen trunks, on stumps of deciduous trees, mainly on birches, elms, beeches, hornbeams, and maples. Causes white rot of wood.
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.

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).