Xylaria hypoxylon
Encyclopedia
Xylaria hypoxylon is an inedible species of fungus
in the genus Xylaria
. It is known by a variety of common name
s, such as the candlestick fungus, the candlesnuff fungus, carbon antlers, or the stag's horn fungus. The fruit bodies
, characterized by erect, elongated black branches with whitened tips, typically grow in clusters on decaying hardwood
. The fungus can cause a root rot in hawthorn
and gooseberry
plants.
The specific epithet is derived from the Greek
words hypo meaning "below", and xylon, meaning "wood".
s) are cylindrical or flattened with dimensions of 3 – tall × 2–8 mm thick. The erect ascocarps are often twisted or bent, and typically sparsely branched, often in a shape resembling an antler's horns. Specimens found earlier in the season, in spring, may be covered completely in asexual spores (conidia), which manifests itself as a white to grayish powdery deposit. Later in the season, mature ascocarps are charcoal-black, and have minute pimple-like bumps called perithecia on the surface. These are minute rounded spore bearing structures with a tiny holes, or ostioles, for the release of sexual spores (ascospores). The perithecia are embedded in the flesh of the ascocarp, the stroma, which is tough, elastic, and white. Within the perithecia, the asci
are 100 × 8 µm.
Ascospores are kidney-shaped, black, and smooth, with dimensions of 10–14 × 4–6 µm
. The asexual spores (mitospores) are ellipsoid in shape, smooth, and hyaline
.
is thicker and not as branched as X. hypoxylon.
. The pyrone
derivative compounds named xylarone and 8,9-dehydroxylarone also have cytotoxic activity. Several cytochalasin
s, compounds that bind to actin
in muscle tissue, have been found in the fungus. X. hypoxylon also contains a carbohydrate
-binding protein, a lectin
, with a unique sugar specificity, and which has potent anti-tumor effects in various tumor cell lines.
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
in the genus Xylaria
Xylaria
Xylaria is a genus of ascomycetous fungi commonly found growing on dead wood. The name comes from the Greek xýlon meaning wood .Two of the common species of the genus are Xylaria hypoxylon and Xylaria polymorpha....
. It is known by a variety of common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
s, such as the candlestick fungus, the candlesnuff fungus, carbon antlers, or the stag's horn fungus. The fruit bodies
Ascocarp
An ascocarp, or ascoma , is the fruiting body of an ascomycete fungus. It consists of very tightly interwoven hyphae and may contain millions of asci, each of which typically contains eight ascospores...
, characterized by erect, elongated black branches with whitened tips, typically grow in clusters on decaying hardwood
Hardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...
. The fungus can cause a root rot in hawthorn
Crataegus
Crataegus , commonly called hawthorn or thornapple, is a large genus of shrubs and trees in the rose family, Rosaceae, native to temperate regions of the Northern Hemisphere in Europe, Asia and North America. The name hawthorn was originally applied to the species native to northern Europe,...
and gooseberry
Gooseberry
The gooseberry or ; Ribes uva-crispa, syn. R. grossularia) is a species of Ribes, native to Europe, northwestern Africa and southwestern Asia...
plants.
Taxonomy
Xylaria hypoxylon was first described by Carl Linnaeus in 1745, and then later mentioned by him in his Species Plantarum II.The specific epithet is derived from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
words hypo meaning "below", and xylon, meaning "wood".
Description
Fruit bodies (ascocarpAscocarp
An ascocarp, or ascoma , is the fruiting body of an ascomycete fungus. It consists of very tightly interwoven hyphae and may contain millions of asci, each of which typically contains eight ascospores...
s) are cylindrical or flattened with dimensions of 3 – tall × 2–8 mm thick. The erect ascocarps are often twisted or bent, and typically sparsely branched, often in a shape resembling an antler's horns. Specimens found earlier in the season, in spring, may be covered completely in asexual spores (conidia), which manifests itself as a white to grayish powdery deposit. Later in the season, mature ascocarps are charcoal-black, and have minute pimple-like bumps called perithecia on the surface. These are minute rounded spore bearing structures with a tiny holes, or ostioles, for the release of sexual spores (ascospores). The perithecia are embedded in the flesh of the ascocarp, the stroma, which is tough, elastic, and white. Within the perithecia, the asci
Ascus
An ascus is the sexual spore-bearing cell produced in ascomycete fungi. On average, asci normally contain eight ascospores, produced by a meiotic cell division followed, in most species, by a mitotic cell division. However, asci in some genera or species can number one , two, four, or multiples...
are 100 × 8 µm.
Ascospores are kidney-shaped, black, and smooth, with dimensions of 10–14 × 4–6 µm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
. The asexual spores (mitospores) are ellipsoid in shape, smooth, and hyaline
Hyaline
The term hyaline denotes a substance with a glass-like appearance.-Histopathology:In histopathological medical usage, a hyaline substance appears glassy and pink after being stained with haematoxylin and eosin — usually it is an acellular, proteinaceous material...
.
Edibility
Although not poisonous, the small size and tough texture of this fungus deter consumption.Similar species
Xylaria polymorphaXylaria polymorpha
Xylaria polymorpha, commonly known as dead man's fingers, is a saprobic fungi. It is a common inhabitant of forest and woodland areas, usually growing from the bases of rotting or injured tree stumps and decaying wood. It has also been known to colonise substrates like woody legume pods, petioles,...
is thicker and not as branched as X. hypoxylon.
Bioactive compounds
A variety of bioactive compounds have been identified in this fungus. The compounds xylarial A and B both have moderate cytotoxic activity against the human hepatocellular carcinoma cell line Hep G2Hep G2
Hep G2 is a human liver carcinoma cell line.-Technical reference:ATCC No. HB-8065 Hep G2 Hep G2 is a perpetual cell line which was derived from the liver tissue of a 15 year old Caucasian American male with a well differentiated hepatocellular carcinoma...
. The pyrone
Pyrone
Pyrones or pyranones are a class of cyclic chemical compounds. They contain an unsaturated six membered ring containing one oxygen atom and a ketone functional group. There are two isomers denoted as 2-pyrone and 4-pyrone. The 2-pyrone structure is found in nature as part of the coumarin ring...
derivative compounds named xylarone and 8,9-dehydroxylarone also have cytotoxic activity. Several cytochalasin
Cytochalasin
Cytochalasins are fungal metabolites that have the ability to bind to actin filaments and block polymerization and the elongation of actin. As a result of the inhibition of actin polymerization, cytochalasins can change cellular morphology, inhibit cellular processes such as cell division, and even...
s, compounds that bind to actin
Actin
Actin is a globular, roughly 42-kDa moonlighting protein found in all eukaryotic cells where it may be present at concentrations of over 100 μM. It is also one of the most highly-conserved proteins, differing by no more than 20% in species as diverse as algae and humans...
in muscle tissue, have been found in the fungus. X. hypoxylon also contains a carbohydrate
Carbohydrate
A carbohydrate is an organic compound with the empirical formula ; that is, consists only of carbon, hydrogen, and oxygen, with a hydrogen:oxygen atom ratio of 2:1 . However, there are exceptions to this. One common example would be deoxyribose, a component of DNA, which has the empirical...
-binding protein, a lectin
Lectin
Lectins are sugar-binding proteins that are highly specific for their sugar moieties. They play a role in biological recognition phenomena involving cells and proteins. For example, some viruses use lectins to attach themselves to the cells of the host organism during infection...
, with a unique sugar specificity, and which has potent anti-tumor effects in various tumor cell lines.
External links
- X. hypoxylon at Index FungorumIndex FungorumIndex Fungorum, an international project to index all formal names in the Fungi Kingdom. Somewhat comparable to the IPNI, but with more contributing institutions....
- Fungi on Wood Description and photos
- Medicinal Mushrooms Medicinal compounds and bioactive compounds