Polyozellus

Template:Short description
Template:Pp-move-indef
Template:Stack begin
Template:Taxobox
Template:Mycomorphbox
Template:Stack end
Template:Italic title
***Polyozellus*** is a fungal genus in the family Thelephoraceae, a grouping of mushrooms known collectively as the leathery earthfans. A monotypic genus, it contains the single species ***Polyozellus multiplex***, first described in 1899, and commonly known as the **blue chanterelle**, the **clustered blue chanterelle**, or, in Alaska, the **black chanterelle**. The distinctive fruit body of this species comprises blue- to purple-colored clusters of vase- or spoon-shaped caps with veiny wrinkles on the undersurface that run down the length of the stem.

*Polyozellus* has had a varied taxonomic history and has been reclassified several times at both the family and genus level. The range of *Polyozellus* includes North America and eastern Asia, where *P. multiplex* may be found growing on the ground in coniferous forests, usually under spruce and fir trees. It is an edible species, and has been harvested for commercial purposes. *Polyozellus multiplex* contains the bioactive compound polyozellin, shown to have various physiological properties, including suppressive effects on stomach cancer.

## History and taxonomy

The first published description of the species was written by botanist Lucien M. Underwood in 1899, based on a specimen found the previous year in the woods of Mount Desert, Maine. Although he called the new species a *Cantharellus*, he noted that "the plant is a remarkable one and from its habit might well form a distinct genus since it has little in common with *Cantharellus* except its fold-like gills." In 1910, William Murrill transferred it to the new genus *Polyozellus*; Murrill thought the compound structure of the stem to be a sufficiently unique characteristic to warrant it being separated from *Cantharellus* species, which have simpler stem structures. In 1920, specimens from a Japanese collection compiled by A. Yasuda were sent to mycologist Curtis Gates Lloyd, who believed the fungus to be a new species and named it *Phyllocarbon yasudai*.

 File:Gomphus clavatus1.jpg  No further collections of the fungus were reported until 1937, when it was found in Quebec, Canada. The next year, Paul Shope considered the genus *Polyozellus* to be superfluous, pointed out that the compound fruit bodies and the wrinkled hymenium were instead consistent with the genus *Craterellus*. In 1939, American mycologist Lee Oras Overholts, in a letter to the journal *Mycologia*, opined that both of these authors had overlooked a 1925 publication by Calvin Henry Kauffman, who made notes and photos of the species collected in the Rocky Mountains of Wyoming and Colorado, and in the Cascade Mountains of Washington and Oregon. Kauffman believed the species to be merely "a very extreme growth condition" of *Cantharellus clavatus* (now known as *Gomphus clavatus*) and suggested there was no reason for transferring the species to the genus *Craterellus*. Mycologists Alexander H. Smith and Elizabeth Eaton Morse, in their 1947 publication on *Cantharellus* species in the United States, placed the species in a new section *Polyozellus*, but did not separate it from the genus *Cantharellus*; they defined the distinguishing characteristics of *Polyozellus* as the small, roughened, hyaline spores and the color change of the flesh in potassium hydroxide solution, adding that "the spores are unusual for the genus but in our estimation do not warrant excluding the species."

 File:Polyozellus multiplex -Haida Guaii.jpg
In 1953, Rokuya Imazeki took into consideration differences in spore characteristics: species in the genus *Cantharellus* were not known to have spores that were subglobose (roughly spherical) and tuberculate (covered with wart-like projections) like *Polyozellus*; however, these spore characteristics were common in species in the Thelephoraceae family (*Cantharellus* belongs in a different family, the Cantharellaceae). Other characteristics linking the blue chanterelle with the Thelephoraceae included the dark color, the strong odor (especially in dried specimens), and the presence of thelephoric acid, a mushroom pigment common in the family. Taken together, these factors led Imazeki to propose the new family Phylacteriaceae. The suggested family-level taxonomical change was not accepted by other authors; for example, in 1954, Seiichi Kawamura renamed it *Thelephora multiplex*. As of 2009, both Index Fungorum and MycoBank list *Polyozellus* as being within the Thelephoraceae family, a grouping of mushrooms commonly known as the leathery earthfans. The genus name is derived from the Greek *poly* meaning *many*, and *oz*, meaning *branch*. The specific epithet *multiplex* means "in many pieces", referring to the compound nature of the fruit body. Common names for this species include the blue chanterelle and the clustered blue chanterelle. In Alaska, where specimens typically have very dark-colored fruit bodies, it is called the black chanterelle, although this name is shared with some *Craterellus* species.

## Description

 File:Polyozellus multiplex 23792.jpg
*Polyozellus multiplex* is part of the group of fungi collectively known as cantharelloid mushrooms (which includes the genera *Cantharellus*, *Craterellus*, *Gomphus*, and *Polyozellus*) because of the similarity of their fruit body structures and the morphology of the spore-producing region (the hymenophore) on the underside of the caps. The fan- or funnel-shaped fruit bodies of the black chanterelle grow clustered together on the ground, often in large masses that may reach aggregate diameters of up to Template:Convert, although they are usually up to Template:Convert.

The individual caps, Template:Convert wide and almost as long, are violet-black, with edges that are initially whitish, and with a glaucous surface—a white powdery accumulation of spore deposit. The upper surface may be zonate—lined with what appear to be multiple concentric zones of texture caused by areas of fine hairs (a tomentum); and the edges of the caps have a layer of very fine hairs and are lobed and wavy. The underside of the caps bears the fertile, spore-making tissue called the hymenium, which typically has shallow, crowded wrinkles or veins that are roughly the same color or paler than the top surface. Some variation in color has been observed depending on the collection location. For example, specimens found in Alaska are more likely to be jet-black in color with a dark gray underside.

Fruit bodies may be up to Template:Convert high (including the stem) and Template:Convert wide. Occasionally, much larger clusters of fused mushrooms are found, up to a meter in diameter. The stem is dark purplish-black with a smooth (glabrous) and dry surface; the stems are often fused at the base. It is typically Template:Convert wide and up to Template:Convert long. The flesh is dark violet, soft but breaking easily. The spore deposit is white.

### Microscopic characteristics

 File:Craterellus cornucopiodes 12457.jpg
The spores are roughly spherical to broadly ellipsoid in shape, covered with small wart-like projections (tubercules), and have dimensions of 6–8.5 by 5.5–8 µm. Viewed microscopically, they are hyaline, meaning they appear translucent or colorless. Chemical tests may also be used to help distinguish the spores: in the presence of potassium hydroxide (KOH), the spores turn slightly green; the spores are not amyloid, meaning they do not take iodine when treated with Melzer's reagent; the spores are acyanophilous, meaning they do not readily absorb methyl blue stain. The cystidia that comprise the hymenium are filamentous and 3–4 µm wide by 28–40 µm long. The outer tissue layer of the cap—the cuticle, or pileipellis—is made of interwoven hyphae, and stains olive-green in KOH. Clamp connections are present, but not at all the cell partitions. The basidia, the spore-bearing cells, are 32–38 by 5–6 µm and four-spored.

### Similar species

The horn-of-plenty mushroom (*Craterellus cornucopioides*) also has a blackish fruit body and a smooth hymenium, but is distinguished from *P. multiplex* by its thin flesh, a trumpet- or tubular-shaped fruit body (rather than fan- or spoon-shaped), and grey to black colors. A closely related species, the fragrant chanterelle (*Cantharellus odoratus*), also tends to grow in dense clusters, but it is orange rather than blue. *Craterellus caeruleofuscus* does not form compound clusters, and is not restricted to coniferous forests. The pig's ear Gomphus, species *Gomphus clavatus*, is similar in shape and form but fleshier, and light violet to pink.

## Habitat and distribution

Template:Multiple image
*Polyozellus multiplex* is an ectomycorrhizal species, meaning that the hyphae of the fungus grow in a mutualistic association with the roots of plants, but the fungal hyphae generally do not penetrate the cells of the plant's roots. The species grows in coniferous woods under spruce and fir, and more frequently at higher elevations. It is most often encountered in summer and fall.

This species is northern and alpine in distribution, and rarely encountered. Collections have been made in the United States (including Maine, Oregon, Colorado, New Mexico, and Alaska), Canada (Quebec and British Columbia), China, Japan, and Korea. The disjunct distribution of this species in North America and East Asia has been noted to occur in a number of other fungal species as well. *Polyozellus multiplex* is also found in the Queen Charlotte Islands, where it is commercially harvested.

## Uses

### Edibility

*Polyozellus multiplex* is edible, and is collected for sale in Asian countries such as Korea, Japan, and China. In North America, it is sometimes collected recreationally, and commercially. The taste is described as mild, and the odor as mild or aromatic. Mycologist David Arora claims the flavor to be inferior to *Craterellus*. Fruit bodies may be preserved by drying.

### Bioactive compounds

 File:Polyozellin.svg
The compound polyozellin—a chemical which can be isolated and purified from *P. multiplex*—inhibits prolyl endopeptidase (PEP), an enzyme that has a role in processing proteins (specifically, amyloid precursor protein) in Alzheimer's disease. Chemicals that inhibit PEP have attracted research interest due to their potential therapeutic effects. Further analyses of extracts from *P. multiplex* revealed similar dibenzofuranyl derivatives of polyozellin, each with different chemical properties, including kynapcin-12, kynapcin-13 and -28, and -24. A total synthesis of kynapcin-24 was achieved in 2009.

### Antitumor properties

Research conducted in 2003 suggests that extracts from *Polyozellus multiplex* may have suppressive effects on stomach cancer. The study showed that feeding a low concentration (0.5% or 1%) of the mushroom extract enhanced the activities of the enzymes glutathione S-transferase and superoxide dismutase, and increased the abundance of the molecule glutathione. The extract also augmented the expression of the protein p53. All of these substances protect the human organism against cancer. Additional studies reported in 2004 and 2006 attribute anti-tumor properties to polyozellin.

## References

1. ↑ 1.0 1.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Underwood1899`
2. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Murrill1910`
3. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Lloyd1921`
4. ↑ 4.0 4.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Mounce1937`
5. ↑ 5.0 5.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Shope1938`
6. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Kauffman1925`
7. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Overholts1939`
8. ↑ 8.0 8.1 8.2 8.3 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Smith1947`
9. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Sawada1952`
10. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Kawamura1954`
11. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `urlFungorum`
12. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `urlStalpers2009`
13. ↑ 13.0 13.1 Pilz *et al*., p. 17.
14. ↑ 14.0 14.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Richard1993`
15. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Weber1980`
16. ↑ 16.0 16.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Ammirati1987`
17. ↑ Pilz *et al*., p. 38.
18. ↑ 18.0 18.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Arora1991`
19. ↑ 19.0 19.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `McKnight1987`
20. ↑ 20.0 20.1 20.2 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Arora1986`
21. ↑ 21.0 21.1 21.2 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Bessette1992`
22. ↑ 22.0 22.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `urlKuo2003`
23. ↑ 23.0 23.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Bigelow1978`
24. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Bessette1987`
25. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Stamets2005`
26. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Lee2000a`
27. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Pomerleau1978`
28. ↑ 28.0 28.1 28.2 28.3 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Lee2003`
29. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Imazeki1953`
30. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Yang2005`
31. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `urlFungi of Haida Gwaii`
32. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Miller2006`
33. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Castellano1997`
34. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Berch2003`
35. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Tylutki1987II`
36. ↑ 36.0 36.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `Hwang1997`
37. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Lee2000`
38. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Kim2002`
39. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Song2002`
40. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Yang2009`
41. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Lull2005`
42. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Kim2004`
43. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Jin2006`

## External links

Template:Wikispecies

* Template:MycoBank
* California Fungi Photo and further information

Template:Featured article
Template:Taxonbar