Astraeus hygrometricus
Encyclopedia
Astraeus hygrometricus, commonly known as the hygroscopic earthstar, the barometer earthstar, or the false earthstar, is a species of fungus
in the Diplocystaceae
family. Young specimens resemble a puffball
when young and unopened. In maturity, the mushroom displays the characteristic earthstar shape that is a result of the outer layer of fruit body tissue splitting open in a star-like manner. The false earthstar is an ectomycorrhizal species that grows in association with various trees, especially in sandy soils. A. hygrometricus has a cosmopolitan distribution
, and is common in temperate and tropical regions. Its common name
s refer to the fact that it is hygroscopic (water-absorbing), and can open up its rays to expose the spore sac in response to increased humidity, and close them up again in drier conditions. The rays have an irregularly cracked surface, while the spore case is pale brown and smooth with an irregular slit or tear at the top. The gleba
is white initially, but turns brown and powdery when the spore
s mature. The spores are reddish-brown, roughly spherical with minute warts, measuring 7.5–11 micrometer
s in diameter.
Despite a similar overall appearance, A. hygrometricus is not related to the true earthstars of genus Geastrum
, although historically, they have been taxonomically
confused. The species was first described by Christiaan Hendrik Persoon in 1801 as Geastrum hygrometricus. In 1885, Andrew P. Morgan proposed that differences in microscopic characteristics warranted the creation of a new genus Astraeus
distinct from Geastrum; this opinion was not universally accepted by later authorities. Several Asian populations formerly thought to be A. hygrometricus were renamed in the 2000s once phylogenetic analyses revealed they were unique Astraeus species, including A. asiaticus
and A. odoratus
. Research has revealed the presence of several bioactive
chemical compounds in the fruit bodies. North American field guides typically rate A. hygrometricus as inedible. The mushroom has been used medicinally by India
n forest tribes, and features in the folklore of the Blackfoot
of North America.
in 1801 (as Geaster, an alternate spelling of Geastrum). According to the American botanist Andrew P. Morgan, however, the species differed from those of Geastrum in not having open chambers in the young gleba
, having larger and branched capillitium threads, not having a true hymenium
, and having larger spores. Accordingly, Morgan set Persoon's Geaster hygrometricum as the type species
of his new genus Astraeus in 1889. Despite Morgan's publication, some authorities in the following decades continued to classify the species in Geastrum. The New-Zealand based mycologist Gordon Herriot Cunningham explicitly transferred the species back to the genus Geastrum in 1944, explaining:
authority MycoBank
, synonyms of Astraeus hygrometricus include Lycoperdon stellatus Scop. (1772); Geastrum fibrillosum Schwein. (1822); Geastrum stellatum (Scop.) Wettst. (1885); and Astraeus stellatus E.Fisch. (1900).
Astraeus hygrometricus has been given a number of colloquial names
that allude to its hygroscopic behavior, including the "hygrometer earthstar", the "hygroscopic earthstar", the "barometer earthstar", and the "water-measure earthstar". The resemblance to Geastrum species (also known as true earthstars) accounts for the common name "false earthstar". The specific name is derived from the Greek
words ὑγρός (hygros) "wet" and μέτρον (metron) "measure". The German Mycological Society selected the species as their "Mushroom of the Year" in 2005.
Studies in the 2000s showed that several species from Asian collection sites labelled under the specific epithet hygrometricus were actually considerably variable in a number of macroscopic and microscopic characteristics. Molecular studies of the DNA sequence
s of the ITS
region of the ribosomal DNA
from a number of Astraeus specimens from around the world have helped to clarify phylogenetic relationships within the genus. Based on these results, two Asian "hygrometricus" populations have been described as new species: A. asiaticus
and A. odoratus
(synonymous with Petcharat's A. thailandicus described in 2003). Preliminary DNA analyses suggests that the European A. hygrometricus described by Persoon is a different species than the North American version described by Morgan, and that the European population may be divided into two distinct phylotype
s, from France and from the Mediterranean. A 2010 study identified a Japanese species, previously identified as A. hygrometricus, as genetically distinct; it has yet to be officially named.
A form of the species found in Korea and Japan, A. hygrometricus var. koreanus, was named by V.J. Stanĕk in 1958; it was later (1976) published as a distinct species—A. koreanus—by Hanns Kreisel
. As pointed out by Fangfuk and colleagues, clarification of the proper name for this taxon must await analysis of A. hygrometricus var. koreanus specimens from the type locality in North Korea.
that typically start their development partially embedded in the substrate
. A smooth whitish mycelial layer covers the fruit body, and may be partially encrusted with debris. As the fruit body matures, the mycelial layer tears away, and the outer tissue layer, the exoperidium
, breaks open in a star-shaped (stellate) pattern to form 4–20 irregular "rays". This simultaneously pushes the fruit body above ground to reveal a round spore case enclosed in a thin papery endoperidium. The rays open and close in response to levels of moisture in the environment, opening up in high humidity, and closing when the air is dry. This is possible because the exoperidium is made of several different layers of tissue; the innermost, fibrous layer is hygroscopic, and curls or uncurls the entire ray as it loses or gains moisture from its surroundings. This adaptation enables the fruit body to disperse spores at times of optimum moisture, and reduce evaporation during dry periods. Further, dry fruit bodies with the rays curled up may be readily blown about by the wind, allowing them to scatter spores from the pore as they roll.
The fruit body is 1 – in diameter from tip to tip when expanded. The exoperidium is thick, and the rays are typically areolate (divided into small areas by cracks and crevices) on the upper surface, and are dark grey to black. The spore case is sessile
(lacking a stalk
), light gray to tan color and 1 to 3 cm (0.393700787401575 to 1.2 in) broad with a felt-like or scurfy (coated with loose scaly crust) surface; the top of the spore case is opened by an irregular slit, tear or pore. The interior of the spore case, the gleba
, is white and solid when young, and divided into oval locule
s—a characteristic that helps to distinguish it from Geastrum. The gleba becomes brown and powdery as the specimen matures. Small dark hairlike threads (rhizomorphs) extend from the base of the fruit body into the substrate. The rhizomorphs are fragile, and often break off after maturity.
The spores
are spherical or nearly so, reddish-brown, thick-walled and verrucose (covered with warts and spines). The spores' dimensions are 7–11 µm
; the warts are about 1 µm long. The spores are non-amyloid
, and will not stain with iodine from Melzer's reagent
. The use of scanning electron microscopy has shown that the spines are 0.90–1.45 µm long, rounded at the tip, narrow, tapered, and sometime joined together at the top. The capillitia (masses of thread-like sterile fibers dispersed among the spores) are branched, 3.5–6.5 µm in diameter, and hyaline
(translucent). The basidia (spore-bearing cells) are four- to eight-spored, with very short sterigmata. The basidia are arranged in long strings of clusters; individual basidia measure 11–15 by 18–24 µm. The threads of the capillitia arise from the inner surface of the peridium, and are thick-walled, long, interwoven, and branched, measuring 3–5.5 µm thick. The exoperidium (the outer layer of tissue, comprising the rays) is made of four distinct layers of tissue: the mycelial layer contains branched hypha
e that are 4–6 μm in diameter; the hyphae of the fibrous layer are 6–8 μm diameter and branched; the collenchyma-type layer has branched hyphae of 3–4 μm diameter; the soft layer contains hyphae that are 3–6 μm in diameter.
, where "local people consume them as delicious food". They are collected from the wild and sold in the markets of India. A study of a closely related southeast Asian Astraeus species concluded that the fungus contained an abundance of volatile
eight-carbon compounds (including octanol
, 1-octen-3-ol
, and 1-octen-3-one) that imparted a "mushroom-like, earthy, and pungent odor that was evident as an oily and moss-like smell upon opening the caps." The study's authors further noted that the fruit bodies after cooking have a "roasted, maillard, herbal, and oily flavor." Volatile compounds detected after cooking the mushroom samples included furfural
, benzaldehyde
, cyclohexenone
, and furan
yl compounds. The regional differences in opinions on edibility are from sources published before it was known that North American and Asian versions of A. hygrometricus were not always the same; in some cases Asian specimens have been identified as new species, such as A. asiaticus and A. odoratus.
, G. floriforme, G. recolligens, and G. kotlabae. Unlike Geastrum, the young fruit bodies of A. hygrometricus do not have a columella (sterile tissue in the gleba, at the base of the spore sac). Geastrum tends to have its spore sac opening surrounded by a peristome
or a disc, in contrast with the single lacerate slit of A. hygrometricus. There are also several microscopic differences: in A. hygrometricus, the basidia are not arranged in parallel columns, the spores are larger, and the threads of the capillitia are branched and continuous with the hyphae of the peridium. Despite these differences, older specimens can be difficult to distinguish from Geastrum in the field. One species of Geastrum, G. mammosum, does have thick and brittle rays that are moderately hygroscopic, and could be confused with A. hygrometricus; however, its spores are smaller than A. hygrometricus, typically about 4 µm in diameter.
Astraeus pteridis
is larger, 5 to 15 cm (2 to 5.9 in) or more when expanded, and often has a more pronounced areolate pattern on the inner surface of the rays. It is found in North America and the Canary Islands
. A. asiaticus
and A. odoratus
are two similar species known from throughout Asia and Southeast Asia
, respectively. A. odoratus is distinguished from A. hygrometricus by a smooth outer mycelial layer with few adhering soil particles, 3–9 broad rays, and a fresh odor similar to moist soil. The spore ornamentation of A. odoratus is also distinct from A. hygrometricus, with longer and narrower spines that often joined together. A. asiaticus has an outer peridial surface covered with small granules, and a gleba that is purplish-chestnut in color, compared to the smooth peridial surface and brownish gleba of A. hygrometricus. The upper limit of the spore size of A. asiaticus is larger than that of its more common relative, ranging from 8.75–15.2 μm. A. koreanus
(sometimes named as the variety A. hygrometricus var. koreanus; see Taxonomy) differs from the more common form in its smaller size, paler fruit body, and greater number of rays; microscopically, it has smaller spores (between 6.8 and 9 μm in diameter), and the spines on the spores differ in length and morphology. It is known from Korea and Japan.
of the fungus helps the trees extract nutrients (particularly phosphorus
) from the earth; in exchange, the fungus receives carbohydrate
s from photosynthesis
. In North America, associations with oak
and pine
are usual, while in India, it has been noted to grow commonly with chir pine
(Pinus roxburghii) and sal (Shorea robusta). The false earthstar is found on the ground in open fields, often scattered or in groups, especially in nutrient-poor, sandy or loam
y soils. It has also been reported to grow on rocks, preferring acid substrates
like slate
and granite
, while avoiding substrates rich in lime. In Nepal, fruit bodies have been collected at elevations of 3000 m (9,842.5 ft). Fruit bodies typically appear in autumn, although the dry fruit bodies are persistent and may last up to several years. Gelatinipulvinella astraeicola is a leotiaceous
fungus with minute, gelatinous, pulvinate (cushion-shaped) apothecia, known to grow only on the inner surface of the rays of dead Astraeus species, including A. hygrometricus.
The species has a cosmopolitan distribution
except for arctic
, alpine
and cold temperate
regions; it is common in temperate
and tropical regions of the world. It has been collected in Africa, Asia, Australia, Europe, North America, and South America.
s from a number of species have attracted research interest for their immunomodulatory and antitumor properties. Extracts from A. hygrometricus containing the polysaccharide named AE2 were found to inhibit the growth of several tumor cell lines
in laboratory tests, and stimulated the growth of splenocyte
s, thymocyte
s, and bone marrow
cells from mice. The extract also stimulated mouse cells associated with the immune system
; specifically, it enhanced the activity of mouse natural killer cell
s, stimulated macrophage
s to produce nitric oxide
, and enhanced production of cytokine
s. The activation of macrophages by AE2 might be mediated by a mitogen-activated protein kinase
pathway of signal transduction
. AE2 is made of the simple sugars mannose
, glucose
, and fucose
in a 1:2:1 ratio.
In addition to the previously known steroid
compounds ergosta-7,22-diene-3-ol acetate and ergosta-4,6,8-(14),22-tetraene-3-one, three unique triterpenes—derivatives
of 3-hydroxy-lanostane
—have been isolated from fruit bodies of A. hygrometricus. The compounds, named astrahygrol, 3-epi-astrahygrol, and astrahygrone (3-oxo-25S-lanost-8-eno-26,22-lactone), have δ-lactone
(a six-membered ring) in the side chain
—a chemical feature previously unknown in the Basidiomycetes. A previously unknown steryl ester (3β, 5α-dihydroxy-(22E, 24R)-ergosta-7,22-dien-6α-yl palmitate) has been isolated from mycelia grown in liquid culture. The compound has a polyhydroxylated ergostane-type nucleus.
Ethanol extracts of the fruit body are high in antioxidant
activity, and have been shown in laboratory tests to have anti-inflammatory
activity comparable to the drug diclofenac
. Studies with mouse models have also demonstrated hepatoprotective (liver-protecting) ability, possibly by restoring diminished levels of the antioxidant enzymes superoxide dismutase
and catalase
caused by experimental exposure to the liver-damaging chemical carbon tetrachloride
.
as a hemostatic agent; the spore dust is applied externally to stop wound bleeding and reduce chilblain
s. Two India
n forest tribes, the Baiga and the Bharia
of Madhya Pradesh
, have been reported to use the fruit bodies medicinally. The spore mass is blended with mustard seed
oil, and used as a salve
against burns. The Blackfoot
of North America called the fungus "fallen stars", considering them to be stars fallen to the earth during supernatural events.
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 Diplocystaceae
Diplocystaceae
Diplocystaceae is a family of fungi in the Boletales order. The family was described by mycologist Hanns Kreisel in 1974....
family. Young specimens resemble a puffball
Puffball
A puffball is a member of any of several groups of fungus in the division Basidiomycota. The puffballs were previously treated as a taxonomic group called the Gasteromycetes or Gasteromycetidae, but they are now known to be a polyphyletic assemblage. The distinguishing feature of all puffballs is...
when young and unopened. In maturity, the mushroom displays the characteristic earthstar shape that is a result of the outer layer of fruit body tissue splitting open in a star-like manner. The false earthstar is an ectomycorrhizal species that grows in association with various trees, especially in sandy soils. A. hygrometricus has a cosmopolitan distribution
Cosmopolitan distribution
In biogeography, a taxon is said to have a cosmopolitan distribution if its range extends across all or most of the world in appropriate habitats. For instance, the killer whale has a cosmopolitan distribution, extending over most of the world's oceans. Other examples include humans, the lichen...
, and is common in temperate and tropical regions. Its 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 refer to the fact that it is hygroscopic (water-absorbing), and can open up its rays to expose the spore sac in response to increased humidity, and close them up again in drier conditions. The rays have an irregularly cracked surface, while the spore case is pale brown and smooth with an irregular slit or tear at the top. The gleba
Gleba
Gleba is the fleshy spore-bearing inner mass of fungi such as the puffball or stinkhorn.The gleba is a solid mass of spores, generated within an enclosed area within the sporocarp. The continuous maturity of the sporogenous cells leave the spores behind as a powdery mass that can be easily blown away...
is white initially, but turns brown and powdery when the spore
Spore
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...
s mature. The spores are reddish-brown, roughly spherical with minute warts, measuring 7.5–11 micrometer
Micrometer
A micrometer , sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw used widely for precise measurement of small distances in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier,...
s in diameter.
Despite a similar overall appearance, A. hygrometricus is not related to the true earthstars of genus Geastrum
Geastrum
Geastrum is a genus of mushroom in the family Geastraceae. Many species are known commonly as earthstars.The name comes from geo meaning earth and aster meaning star....
, although historically, they have been taxonomically
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
confused. The species was first described by Christiaan Hendrik Persoon in 1801 as Geastrum hygrometricus. In 1885, Andrew P. Morgan proposed that differences in microscopic characteristics warranted the creation of a new genus Astraeus
Astraeus (genus)
Astraeus is a genus of fungi in the Diplocystaceae family. The genus, which has a cosmopolitan distribution, contains five species of earthstar mushrooms. They are distinguished by the outer layer of flesh that at maturity splits open in a star-shape manner to reveal a round spore sac...
distinct from Geastrum; this opinion was not universally accepted by later authorities. Several Asian populations formerly thought to be A. hygrometricus were renamed in the 2000s once phylogenetic analyses revealed they were unique Astraeus species, including A. asiaticus
Astraeus asiaticus
Astraeus asiaticus is a species of false earthstar in the family Diplocystaceae. Described as a new species in 2007, it was originally found in north and northeastern areas of Thailand, where it grows in sandy or laterite-rich soil in dry lowland dipterocarp forests. The species has a wide...
and A. odoratus
Astraeus odoratus
Astraeus odoratus is a species of false earthstar in the family Diplocystaceae. Described as a new species in 2004, it was originally found in Thailand growing in sandy or laterite-rich soil in dry lowland dipterocarp forests. The species is found in Southeast Asia.-Description:Fruit bodies begin...
. Research has revealed the presence of several bioactive
Biological activity
In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or pharmacophore but can be modified by the other...
chemical compounds in the fruit bodies. North American field guides typically rate A. hygrometricus as inedible. The mushroom has been used medicinally by India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
n forest tribes, and features in the folklore of the Blackfoot
Blackfoot
The Blackfoot Confederacy or Niitsítapi is the collective name of three First Nations in Alberta and one Native American tribe in Montana....
of North America.
Taxonomy, naming, and phylogeny
Because this species resembles the earthstar fungi of Geastrum, it was placed in that genus by early authors, starting with Christian Hendrik PersoonChristian Hendrik Persoon
Christiaan Hendrik Persoon was a mycologist who made additions to Linnaeus' mushroom taxonomy.-Early life:...
in 1801 (as Geaster, an alternate spelling of Geastrum). According to the American botanist Andrew P. Morgan, however, the species differed from those of Geastrum in not having open chambers in the young gleba
Gleba
Gleba is the fleshy spore-bearing inner mass of fungi such as the puffball or stinkhorn.The gleba is a solid mass of spores, generated within an enclosed area within the sporocarp. The continuous maturity of the sporogenous cells leave the spores behind as a powdery mass that can be easily blown away...
, having larger and branched capillitium threads, not having a true hymenium
Hymenium
The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some cells develop into sterile cells called cystidia or...
, and having larger spores. Accordingly, Morgan set Persoon's Geaster hygrometricum as the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
of his new genus Astraeus in 1889. Despite Morgan's publication, some authorities in the following decades continued to classify the species in Geastrum. The New-Zealand based mycologist Gordon Herriot Cunningham explicitly transferred the species back to the genus Geastrum in 1944, explaining:
The treatment of this species by certain taxonomists well illustrates the pitfalls that lie in wait for those who worship at the shrine of ontogenic classification ... The only feature of those outlined in which the species differs from others of Geastrum is the somewhat primitive hymenium. In the developing plant the glebal cavities are separated by tramal plates so tenuous as to be overlooked by the uncritical worker. Each cavity is filled with basidia somewhat irregularly arranged in clusters (like those of SclerodermaCunningham's treatment was not followed by later authorities, who largely considered Astraeus a distinct genus. According to the taxonomicalSclerodermaSystemic sclerosis or systemic scleroderma is a systemic autoimmune disease or systemic connective tissue disease that is a subtype of scleroderma.-Skin symptoms:...
) and not in the definite palisade of the species which have been studied. This difference disappears as maturity is reached, when plants resemble closely the fructification of any other member of the genus. The taxonomist is then unable to indicate any point of difference by which "Astraeus" may be separated from Geastrum, which indicates that the name should be discarded.
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
authority MycoBank
MycoBank
MycoBank is an online database, documenting new mycological names and combinations, eventually combined with descriptions and illustrations. It is run by the Centraalbureau voor Schimmelcultures fungal biodiversity center in Utrecht....
, synonyms of Astraeus hygrometricus include Lycoperdon stellatus Scop. (1772); Geastrum fibrillosum Schwein. (1822); Geastrum stellatum (Scop.) Wettst. (1885); and Astraeus stellatus E.Fisch. (1900).
Astraeus hygrometricus has been given a number of colloquial names
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...
that allude to its hygroscopic behavior, including the "hygrometer earthstar", the "hygroscopic earthstar", the "barometer earthstar", and the "water-measure earthstar". The resemblance to Geastrum species (also known as true earthstars) accounts for the common name "false earthstar". The specific name 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 ὑγρός (hygros) "wet" and μέτρον (metron) "measure". The German Mycological Society selected the species as their "Mushroom of the Year" in 2005.
Studies in the 2000s showed that several species from Asian collection sites labelled under the specific epithet hygrometricus were actually considerably variable in a number of macroscopic and microscopic characteristics. Molecular studies of the DNA sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
s of the ITS
Internal transcribed spacer
ITS refers to a piece of non-functional RNA situated between structural ribosomal RNAs on a common precursor transcript. Read from 5' to 3', this polycistronic rRNA precursor transcript contains the 5' external transcribed sequence , 18S rRNA, ITS1, 5.8S rRNA, ITS2, 28S rRNA and finally the 3'ETS...
region of the ribosomal DNA
Ribosomal DNA
Ribosomal DNA codes for ribosomal RNA. The ribosome is an intracellular macromolecule that produces proteins or polypeptide chains. The ribosome itself consists of a composite of proteins and RNA. As shown in the figure, rDNA consists of a tandem repeat of a unit segment, an operon, composed of...
from a number of Astraeus specimens from around the world have helped to clarify phylogenetic relationships within the genus. Based on these results, two Asian "hygrometricus" populations have been described as new species: A. asiaticus
Astraeus asiaticus
Astraeus asiaticus is a species of false earthstar in the family Diplocystaceae. Described as a new species in 2007, it was originally found in north and northeastern areas of Thailand, where it grows in sandy or laterite-rich soil in dry lowland dipterocarp forests. The species has a wide...
and A. odoratus
Astraeus odoratus
Astraeus odoratus is a species of false earthstar in the family Diplocystaceae. Described as a new species in 2004, it was originally found in Thailand growing in sandy or laterite-rich soil in dry lowland dipterocarp forests. The species is found in Southeast Asia.-Description:Fruit bodies begin...
(synonymous with Petcharat's A. thailandicus described in 2003). Preliminary DNA analyses suggests that the European A. hygrometricus described by Persoon is a different species than the North American version described by Morgan, and that the European population may be divided into two distinct phylotype
Phylotype
A phylotype is biological type that classifies an organism by its phylogenetic, that is evolutionary, relationship to other organisms. The term phylotype is taxon-neutral, thus one can choose the phylogenetic level at which the phylotype is described, e.g. species, class, 97% genetic similarity or...
s, from France and from the Mediterranean. A 2010 study identified a Japanese species, previously identified as A. hygrometricus, as genetically distinct; it has yet to be officially named.
A form of the species found in Korea and Japan, A. hygrometricus var. koreanus, was named by V.J. Stanĕk in 1958; it was later (1976) published as a distinct species—A. koreanus—by Hanns Kreisel
Hanns Kreisel
Hanns Kreisel is a German mycologist and professor emeritus.Kreisel was a professor at the University of Greifswald. His field is the classification of fungi, where he has studied this group of organisms not only in Germany but in almost all continents, as in Brazil, Seychelles, Vietnam, Cuba and...
. As pointed out by Fangfuk and colleagues, clarification of the proper name for this taxon must await analysis of A. hygrometricus var. koreanus specimens from the type locality in North Korea.
Description
Young specimens of A. hygrometricus have roughly spherical fruit bodiesSporocarp (fungi)
In fungi, the sporocarp is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne...
that typically start their development partially embedded in the substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
. A smooth whitish mycelial layer covers the fruit body, and may be partially encrusted with debris. As the fruit body matures, the mycelial layer tears away, and the outer tissue layer, the exoperidium
Peridium
The peridium is the protective layer that encloses a mass of spores in fungi. This outer covering is a distinctive feature of the Gasteromycetes.-Description:...
, breaks open in a star-shaped (stellate) pattern to form 4–20 irregular "rays". This simultaneously pushes the fruit body above ground to reveal a round spore case enclosed in a thin papery endoperidium. The rays open and close in response to levels of moisture in the environment, opening up in high humidity, and closing when the air is dry. This is possible because the exoperidium is made of several different layers of tissue; the innermost, fibrous layer is hygroscopic, and curls or uncurls the entire ray as it loses or gains moisture from its surroundings. This adaptation enables the fruit body to disperse spores at times of optimum moisture, and reduce evaporation during dry periods. Further, dry fruit bodies with the rays curled up may be readily blown about by the wind, allowing them to scatter spores from the pore as they roll.
The fruit body is 1 – in diameter from tip to tip when expanded. The exoperidium is thick, and the rays are typically areolate (divided into small areas by cracks and crevices) on the upper surface, and are dark grey to black. The spore case is sessile
Sessility (botany)
In botany, sessility is a characteristic of plants whose flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel...
(lacking a stalk
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
), light gray to tan color and 1 to 3 cm (0.393700787401575 to 1.2 in) broad with a felt-like or scurfy (coated with loose scaly crust) surface; the top of the spore case is opened by an irregular slit, tear or pore. The interior of the spore case, the gleba
Gleba
Gleba is the fleshy spore-bearing inner mass of fungi such as the puffball or stinkhorn.The gleba is a solid mass of spores, generated within an enclosed area within the sporocarp. The continuous maturity of the sporogenous cells leave the spores behind as a powdery mass that can be easily blown away...
, is white and solid when young, and divided into oval locule
Locule
A locule is a small cavity or compartment within an organ or part of an organism ....
s—a characteristic that helps to distinguish it from Geastrum. The gleba becomes brown and powdery as the specimen matures. Small dark hairlike threads (rhizomorphs) extend from the base of the fruit body into the substrate. The rhizomorphs are fragile, and often break off after maturity.
The spores
Basidiospore
A basidiospore is a reproductive spore produced by Basidiomycete fungi. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. In grills under a cap of one common species in the phylum of...
are spherical or nearly so, reddish-brown, thick-walled and verrucose (covered with warts and spines). The spores' dimensions are 7–11 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 warts are about 1 µm long. The spores are non-amyloid
Amyloid
Amyloids are insoluble fibrous protein aggregates sharing specific structural traits. Abnormal accumulation of amyloid in organs may lead to amyloidosis, and may play a role in various neurodegenerative diseases.-Definition:...
, and will not stain with iodine from Melzer's reagent
Melzer's Reagent
Melzer's reagent is a chemical reagent used by mycologists to assist with the identification of fungi.-Composition:...
. The use of scanning electron microscopy has shown that the spines are 0.90–1.45 µm long, rounded at the tip, narrow, tapered, and sometime joined together at the top. The capillitia (masses of thread-like sterile fibers dispersed among the spores) are branched, 3.5–6.5 µm in diameter, 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...
(translucent). The basidia (spore-bearing cells) are four- to eight-spored, with very short sterigmata. The basidia are arranged in long strings of clusters; individual basidia measure 11–15 by 18–24 µm. The threads of the capillitia arise from the inner surface of the peridium, and are thick-walled, long, interwoven, and branched, measuring 3–5.5 µm thick. The exoperidium (the outer layer of tissue, comprising the rays) is made of four distinct layers of tissue: the mycelial layer contains branched hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e that are 4–6 μm in diameter; the hyphae of the fibrous layer are 6–8 μm diameter and branched; the collenchyma-type layer has branched hyphae of 3–4 μm diameter; the soft layer contains hyphae that are 3–6 μm in diameter.
Edibility
North American sources describe A. hygrometricus as being of either unknown edibility, or too tough to be edible. However, they are regularly consumed in Asia, including Nepal and South BengalBengal
Bengal is a historical and geographical region in the northeast region of the Indian Subcontinent at the apex of the Bay of Bengal. Today, it is mainly divided between the sovereign land of People's Republic of Bangladesh and the Indian state of West Bengal, although some regions of the previous...
, where "local people consume them as delicious food". They are collected from the wild and sold in the markets of India. A study of a closely related southeast Asian Astraeus species concluded that the fungus contained an abundance of volatile
Volatility (chemistry)
In chemistry and physics, volatility is the tendency of a substance to vaporize. Volatility is directly related to a substance's vapor pressure. At a given temperature, a substance with higher vapor pressure vaporizes more readily than a substance with a lower vapor pressure.The term is primarily...
eight-carbon compounds (including octanol
Octanol
Octanol is a straight chain fatty alcohol with eight carbon atoms and the molecular formula CH37OH. Although the term octanol usually refers exclusively to the primary alcohol 1-octanol, there are other less common isomers of octanol such as the secondary alcohols 2-octanol, 3-octanol and...
, 1-octen-3-ol
1-Octen-3-ol
1-Octen-3-ol, octenol for short , is a chemical that attracts biting insects such as mosquitos. It is contained in human breath and sweat, and it was once believed that insect repellent DEET works by blocking the insects' octenol odorant receptors.Octenol is used in combination with carbon dioxide...
, and 1-octen-3-one) that imparted a "mushroom-like, earthy, and pungent odor that was evident as an oily and moss-like smell upon opening the caps." The study's authors further noted that the fruit bodies after cooking have a "roasted, maillard, herbal, and oily flavor." Volatile compounds detected after cooking the mushroom samples included furfural
Furfural
Furfural is an organic compound derived from a variety of agricultural byproducts, including corncobs, oat, wheat bran, and sawdust. The name furfural comes from the Latin word , meaning bran, referring to its usual source....
, benzaldehyde
Benzaldehyde
Benzaldehyde is an organic compound consisting of a benzene ring with a formyl substituent. It is the simplest aromatic aldehyde and one of the most industrially useful. This colorless liquid has a characteristic pleasant almond-like odor...
, cyclohexenone
Cyclohexenone
Cyclohexenone is an organic compound which is a versatile intermediate used in the synthesis of a variety of chemical products such as pharmaceuticals and fragrances...
, and furan
Furan
Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen. The class of compounds containing such rings are also referred to as furans....
yl compounds. The regional differences in opinions on edibility are from sources published before it was known that North American and Asian versions of A. hygrometricus were not always the same; in some cases Asian specimens have been identified as new species, such as A. asiaticus and A. odoratus.
Similar species
Although A. hygrometricus bears a superficial resemblance to member of the "true earthstars" Geastrum, it may be readily differentiated from most by the hygroscopic nature of its rays. Hygroscopic earthstars include G. arenarium, G. corollinumGeastrum corollinum
Geastrum corollinum is an inedible species of mushroom belonging to the genus Geastrum, or earthstar fungi.-External links:*...
, G. floriforme, G. recolligens, and G. kotlabae. Unlike Geastrum, the young fruit bodies of A. hygrometricus do not have a columella (sterile tissue in the gleba, at the base of the spore sac). Geastrum tends to have its spore sac opening surrounded by a peristome
Peristome
The word peristome is derived from the Greek peri, meaning 'around' or 'about', and stoma, 'mouth'. It is a term used to describe various anatomical features that surround an opening to an organ or structure. The term is used in plants and invertebrate animals, such as in describing the shells of...
or a disc, in contrast with the single lacerate slit of A. hygrometricus. There are also several microscopic differences: in A. hygrometricus, the basidia are not arranged in parallel columns, the spores are larger, and the threads of the capillitia are branched and continuous with the hyphae of the peridium. Despite these differences, older specimens can be difficult to distinguish from Geastrum in the field. One species of Geastrum, G. mammosum, does have thick and brittle rays that are moderately hygroscopic, and could be confused with A. hygrometricus; however, its spores are smaller than A. hygrometricus, typically about 4 µm in diameter.
Astraeus pteridis
Astraeus pteridis
Astraeus pteridis is a species of false earthstar in the family Diplocystaceae. It was described by American mycologist Cornelius Lott Shear in 1902 under the name Scleroderma pteridis. Sanford Myron Zeller transferred it to Astraeus in a 1948 publication. It is found in North America....
is larger, 5 to 15 cm (2 to 5.9 in) or more when expanded, and often has a more pronounced areolate pattern on the inner surface of the rays. It is found in North America and the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
. A. asiaticus
Astraeus asiaticus
Astraeus asiaticus is a species of false earthstar in the family Diplocystaceae. Described as a new species in 2007, it was originally found in north and northeastern areas of Thailand, where it grows in sandy or laterite-rich soil in dry lowland dipterocarp forests. The species has a wide...
and A. odoratus
Astraeus odoratus
Astraeus odoratus is a species of false earthstar in the family Diplocystaceae. Described as a new species in 2004, it was originally found in Thailand growing in sandy or laterite-rich soil in dry lowland dipterocarp forests. The species is found in Southeast Asia.-Description:Fruit bodies begin...
are two similar species known from throughout Asia and Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
, respectively. A. odoratus is distinguished from A. hygrometricus by a smooth outer mycelial layer with few adhering soil particles, 3–9 broad rays, and a fresh odor similar to moist soil. The spore ornamentation of A. odoratus is also distinct from A. hygrometricus, with longer and narrower spines that often joined together. A. asiaticus has an outer peridial surface covered with small granules, and a gleba that is purplish-chestnut in color, compared to the smooth peridial surface and brownish gleba of A. hygrometricus. The upper limit of the spore size of A. asiaticus is larger than that of its more common relative, ranging from 8.75–15.2 μm. A. koreanus
Astraeus koreanus
Astraeus koreanus is a species of false earthstar in the family Diplocystaceae. Described as a new species in 1976, it is found in Korea. The species was originally named as a variety koreanus of Astraeus hygrometricus in 1958....
(sometimes named as the variety A. hygrometricus var. koreanus; see Taxonomy) differs from the more common form in its smaller size, paler fruit body, and greater number of rays; microscopically, it has smaller spores (between 6.8 and 9 μm in diameter), and the spines on the spores differ in length and morphology. It is known from Korea and Japan.
Habitat, distribution, and ecology
Astraeus hygrometricus is an ectomycorrhizal fungus and grows in association with a broad range of tree species. The mutualistic association between tree roots and the myceliumMycelium
thumb|right|Fungal myceliaMycelium is the vegetative part of a fungus, consisting of a mass of branching, thread-like hyphae. The mass of hyphae is sometimes called shiro, especially within the fairy ring fungi. Fungal colonies composed of mycelia are found in soil and on or within many other...
of the fungus helps the trees extract nutrients (particularly phosphorus
Phosphorus
Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...
) from the earth; in exchange, the fungus receives 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...
s from photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
. In North America, associations with oak
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
and pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...
are usual, while in India, it has been noted to grow commonly with chir pine
Chir Pine
The Chir Pine, Pinus roxburghii, named after William Roxburgh, is a pine native to the Himalaya.The range extends from northern Pakistan , across northern India and Nepal to Bhutan.It generally occurs at lower altitudes than other pines in the Himalaya, from...
(Pinus roxburghii) and sal (Shorea robusta). The false earthstar is found on the ground in open fields, often scattered or in groups, especially in nutrient-poor, sandy or loam
Loam
Loam is soil composed of sand, silt, and clay in relatively even concentration . Loam soils generally contain more nutrients and humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to till than clay soils...
y soils. It has also been reported to grow on rocks, preferring acid substrates
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
like slate
Slate
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. The result is a foliated rock in which the foliation may not correspond to the original sedimentary layering...
and granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
, while avoiding substrates rich in lime. In Nepal, fruit bodies have been collected at elevations of 3000 m (9,842.5 ft). Fruit bodies typically appear in autumn, although the dry fruit bodies are persistent and may last up to several years. Gelatinipulvinella astraeicola is a leotiaceous
Leotiaceae
The Leotiaceae are a family of fungi in the order Leotiales. Species in this family are saprobic, and have a wide distribution, especially in temperate regions. The family contains 7 genera and 34 species....
fungus with minute, gelatinous, pulvinate (cushion-shaped) apothecia, known to grow only on the inner surface of the rays of dead Astraeus species, including A. hygrometricus.
The species has a cosmopolitan distribution
Cosmopolitan distribution
In biogeography, a taxon is said to have a cosmopolitan distribution if its range extends across all or most of the world in appropriate habitats. For instance, the killer whale has a cosmopolitan distribution, extending over most of the world's oceans. Other examples include humans, the lichen...
except for arctic
Climate of the Arctic
The climate of the Arctic is characterized by long, cold winters and short, cool summers. There is a large amount of variability in climate across the Arctic, but all regions experience extremes of solar radiation in both summer and winter...
, alpine
Alpine climate
Alpine climate is the average weather for a region above the tree line. This climate is also referred to as mountain climate or highland climate....
and cold temperate
Temperate
In geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...
regions; it is common in temperate
Temperate
In geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...
and tropical regions of the world. It has been collected in Africa, Asia, Australia, Europe, North America, and South America.
Bioactive compounds
Mushroom polysaccharidePolysaccharide
Polysaccharides are long carbohydrate molecules, of repeated monomer units joined together by glycosidic bonds. They range in structure from linear to highly branched. Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit. Depending on the structure,...
s from a number of species have attracted research interest for their immunomodulatory and antitumor properties. Extracts from A. hygrometricus containing the polysaccharide named AE2 were found to inhibit the growth of several tumor cell lines
Cell culture
Cell culture is the complex process by which cells are grown under controlled conditions. In practice, the term "cell culture" has come to refer to the culturing of cells derived from singlecellular eukaryotes, especially animal cells. However, there are also cultures of plants, fungi and microbes,...
in laboratory tests, and stimulated the growth of splenocyte
Splenocyte
A splenocyte can be any one of the different white blood cell types as long as it is situated in the spleen or purified from splenic tissue.It sometimes explicitly refers to monocytes or macrophages....
s, thymocyte
Thymocyte
Thymocytes are hematopoietic progenitor cells present in the thymus. Thymopoiesis is the process in the thymus by which thymocytes differentiate into mature T lymphocytes. The primary function of thymocytes is the generation of T lymphocytes . The thymus provides an inductive environment, which...
s, and bone marrow
Bone marrow
Bone marrow is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg , bone marrow accounts for approximately 2.6 kg...
cells from mice. The extract also stimulated mouse cells associated with the immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
; specifically, it enhanced the activity of mouse natural killer cell
Natural killer cell
Natural killer cells are a type of cytotoxic lymphocyte that constitute a major component of the innate immune system. NK cells play a major role in the rejection of tumors and cells infected by viruses...
s, stimulated macrophage
Macrophage
Macrophages are cells produced by the differentiation of monocytes in tissues. Human macrophages are about in diameter. Monocytes and macrophages are phagocytes. Macrophages function in both non-specific defense as well as help initiate specific defense mechanisms of vertebrate animals...
s to produce nitric oxide
Nitric oxide
Nitric oxide, also known as nitrogen monoxide, is a diatomic molecule with chemical formula NO. It is a free radical and is an important intermediate in the chemical industry...
, and enhanced production of cytokine
Cytokine
Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...
s. The activation of macrophages by AE2 might be mediated by a mitogen-activated protein kinase
Mitogen-activated protein kinase
Mitogen-activated protein kinases are serine/threonine-specific protein kinases that respond to extracellular stimuli and regulate various cellular activities, such as gene expression, mitosis, differentiation, proliferation, and cell survival/apoptosis.-Activation:MAP kinases are activated...
pathway of signal transduction
Signal transduction
Signal transduction occurs when an extracellular signaling molecule activates a cell surface receptor. In turn, this receptor alters intracellular molecules creating a response...
. AE2 is made of the simple sugars mannose
Mannose
Mannose is a sugar monomer of the aldohexose series of carbohydrates. Mannose is a C-2 epimer of glucose. It is not part of human metabolism, but is a component of microbial cell walls, and is therefore a target of the immune system and also of antibiotics....
, glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
, and fucose
Fucose
Fucose is a hexose deoxy sugar with the chemical formula C6H12O5. It is found on N-linked glycans on the mammalian, insect and plant cell surface, and is the fundamental sub-unit of the fucoidan polysaccharide...
in a 1:2:1 ratio.
In addition to the previously known steroid
Steroid
A steroid is a type of organic compound that contains a characteristic arrangement of four cycloalkane rings that are joined to each other. Examples of steroids include the dietary fat cholesterol, the sex hormones estradiol and testosterone, and the anti-inflammatory drug dexamethasone.The core...
compounds ergosta-7,22-diene-3-ol acetate and ergosta-4,6,8-(14),22-tetraene-3-one, three unique triterpenes—derivatives
Derivative (chemistry)
In chemistry, a derivative is a compound that is derived from a similar compound by some chemical or physical process. In the past it was also used to mean a compound that can be imagined to arise from another compound, if one atom is replaced with another atom or group of atoms, but modern...
of 3-hydroxy-lanostane
Lanostane
Lanostane or 4,4,14-trimethylcholestane is a chemical compound with formula . It is a polycyclic hydrocarbon, specifically a triterpene...
—have been isolated from fruit bodies of A. hygrometricus. The compounds, named astrahygrol, 3-epi-astrahygrol, and astrahygrone (3-oxo-25S-lanost-8-eno-26,22-lactone), have δ-lactone
Lactone
In chemistry, a lactone is a cyclic ester which can be seen as the condensation product of an alcohol group -OH and a carboxylic acid group -COOH in the same molecule...
(a six-membered ring) in the side chain
Side chain
In organic chemistry and biochemistry, a side chain is a chemical group that is attached to a core part of the molecule called "main chain" or backbone. The placeholder R is often used as a generic placeholder for alkyl group side chains in chemical structure diagrams. To indicate other non-carbon...
—a chemical feature previously unknown in the Basidiomycetes. A previously unknown steryl ester (3β, 5α-dihydroxy-(22E, 24R)-ergosta-7,22-dien-6α-yl palmitate) has been isolated from mycelia grown in liquid culture. The compound has a polyhydroxylated ergostane-type nucleus.
Ethanol extracts of the fruit body are high in antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
activity, and have been shown in laboratory tests to have anti-inflammatory
Anti-inflammatory
Anti-inflammatory refers to the property of a substance or treatment that reduces inflammation. Anti-inflammatory drugs make up about half of analgesics, remedying pain by reducing inflammation as opposed to opioids, which affect the central nervous system....
activity comparable to the drug diclofenac
Diclofenac
Diclofenac is a non-steroidal anti-inflammatory drug taken to reduce inflammation and as an analgesic reducing pain in certain conditions....
. Studies with mouse models have also demonstrated hepatoprotective (liver-protecting) ability, possibly by restoring diminished levels of the antioxidant enzymes superoxide dismutase
Superoxide dismutase
Superoxide dismutases are a class of enzymes that catalyze the dismutation of superoxide into oxygen and hydrogen peroxide. As such, they are an important antioxidant defense in nearly all cells exposed to oxygen...
and catalase
Catalase
Catalase is a common enzyme found in nearly all living organisms that are exposed to oxygen, where it catalyzes the decomposition of hydrogen peroxide to water and oxygen...
caused by experimental exposure to the liver-damaging chemical carbon tetrachloride
Carbon tetrachloride
Carbon tetrachloride, also known by many other names is the organic compound with the formula CCl4. It was formerly widely used in fire extinguishers, as a precursor to refrigerants, and as a cleaning agent...
.
Traditional beliefs
This earthstar has been used in traditional Chinese medicineTraditional Chinese medicine
Traditional Chinese Medicine refers to a broad range of medicine practices sharing common theoretical concepts which have been developed in China and are based on a tradition of more than 2,000 years, including various forms of herbal medicine, acupuncture, massage , exercise , and dietary therapy...
as a hemostatic agent; the spore dust is applied externally to stop wound bleeding and reduce chilblain
Chilblain
Chilblains are a medical condition that is often confused with frostbite and trench foot. Chilblains are acral ulcers that occur when a predisposed individual is exposed to cold and humidity. The cold exposure damages capillary beds in the skin, which in turn can cause redness, itching, blisters,...
s. Two India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
n forest tribes, the Baiga and the Bharia
Bharia
Bharia is one of tribes of Madhya Pradesh in India.The Bharias live in Patalkot, which is completely isolated valley some 400 metres below Tamia in Chhindwara district of Madhya Pradesh.This valley is the source of Dudhi River...
of Madhya Pradesh
Madhya Pradesh
Madhya Pradesh , often called the Heart of India, is a state in central India. Its capital is Bhopal and Indore is the largest city....
, have been reported to use the fruit bodies medicinally. The spore mass is blended with mustard seed
Mustard seed
Mustard seeds are the small round seeds of various mustard plants. The seeds are usually about 1 or 2 mm in diameter. Mustard seeds may be colored from yellowish white to black. They are important spices in many regional foods. The seeds can come from three different plants: black mustard , brown...
oil, and used as a salve
Salve
A salve is a medical ointment used to soothe the head or other body surface. A popular eye medicine known as "Phrygian powder" was one of Laodicea's sources of wealth...
against burns. The Blackfoot
Blackfoot
The Blackfoot Confederacy or Niitsítapi is the collective name of three First Nations in Alberta and one Native American tribe in Montana....
of North America called the fungus "fallen stars", considering them to be stars fallen to the earth during supernatural events.