Suillus americanus
Encyclopedia
Suillus americanus is a species of fungus
in the Suillaceae
family of mushroom
s. Commonly known as the chicken fat mushroom, the American slippery Jack (or slipperycap), or the American suillus, it grows in a mycorrhizal association with eastern white pine
and can be found where this tree occurs in eastern North America and China. The mushroom can be recognized by the bright yellow cap
with red to reddish-brown scales embedded in slime, the large yellow angular pores on the underside of the cap, and the narrow yellow stem
marked with dark reddish dots. Molecular phylogenetics analysis suggests that S. americanus may be the same species as S. sibiricus
, found in western North America and western and central Asia. Suillus americanus is edible
, although opinions vary as to its palatability
; some susceptible individuals may suffer a contact dermatitis
after touching the fruit bodies
. The fruit bodies contain a beta glucan carbohydrate shown in laboratory tests to have anti-inflammatory
properties.
Suillus americanus was first described scientifically by American mycologist Charles Horton Peck
in 1888, based on specimens he had originally collected as far back as 1869, in New York
state, near Sand Lake
, Albany
, and Port Jefferson
. In his 1888 publication he indicated that he had originally listed these collections as Boletus flavidus (now known as Suillus flavidus) in his 1869 Report of the State Botanist (published in 1872). However, as was pointed out nearly a century later in 1986, the 1869 report does not actually mention the species; rather, Peck's field notes that year (which served as the basis for the report) reference a collection at Sand Lake upon which the original (1888) description was most likely based. Because Peck failed to designate a type specimen, one of the Sand Lake specimens was lectotypified
in 1986.
In 1931, French mycologist Jean-Edouard Gilbert transferred the species to the genus Ixocomus, a now-defunct taxon that has since been subsumed into Suillus. In 1959, Walter H. Snell
, collaborating with Rolf Singer
and Esther A. Dick, transferred the species to Suillus. In his 1986 version of the authoritative monograph
The Agaricales in Modern Taxonomy, Singer included the species in the subsection Latiporini of genus Suillus
, an infrageneric grouping (below the taxonomic
level of genus) characterized by a cinnamon-colored spore print
without an olive tinge, and wide pores, typically greater than 1 mm when mature.
Common name
s for the species include the American slipperycap, the American suillus, or the chicken-fat mushroom. The latter name is a reference to its yellow color. The specific epithet americanus means "of America".
is typically between 3 – in diameter, broadly convex with a small umbo (a central elevation) to flat with age. The cap margin is curved inwards in young specimens, and may have remnants of a yellowish, cottony veil hanging from it. The cap surface is colored bright yellow with red or brownish streaks and hairy patches. When the fruit body is young and moist, the surface is slimy; as the cap matures and dries out, it becomes sticky or tacky.
The tubes which comprise the pore layer on the underside of the cap are 0.4 to 0.6 cm (0.15748031496063 to 0.236220472440945 in) deep, and have an adnate (attached broadly to the stem) to decurrent (running down the length of the stem) attachment to the stem. They are yellow, and stain reddish-brown when bruised. The yellow pores are large (1–2 mm diameter) and angular, and tend to become darker as they age. The pores are slightly wider than long, so that there are about 9–10 pores per centimeter measured radially, but 12 to 13 per centimeter when measured tangentially, about halfway to the edge. As is the case with all boletes, spores
form on the inner surfaces of the tubes and sift through their openings to be borne away on the air currents outside.
The stem
is 3 – by 0.4 –, roughly equal in width throughout, often crooked, and becomes hollow with age. The color of the stem surface is lemon yellow, and it is covered with glandular dots that bruise if handled. The partial veil
is not attached to the stem, and usually does not leave an ring
on the stem. A whitish mycelium
present at the base of the stem helps anchor the fruit body in the substrate
. The flesh
is mustard yellow, and stains pinkish-brown when cut or bruised.
, the spores
are cinnamon-colored. Viewed with a microscope, they are pale yellow, smooth, and roughly elliptical in shape, and measure 8–9.5 by 3.5–5 µm
. The basidia, the spore-bearing cells, are club-shaped and 4-spored, with dimensions of 21–25 by 5.5 to 6 µm. The pleurocystidia (cystidia found on the sides of a gill) range in shape from cylindrical to club-shaped and are arranged in bundles. Both the bases of the bundles and the surface of the cystidia may be covered with brown pigment
particles. Cheilocystidia are cystidia located in the gill faces. In S. americanus, they are mostly club-shaped, often with an expanded apex, and like the pleurocystidia, are arranged in bundles, with brown pigment particles at the base of the bundles. Bundles of cystidia near the tube openings may sometimes be visible with a hand lens. Like all Suillus species, the cystidia of S. americanus will turn orange-brown in the presence of a solution of 3% potassium hydroxide
. The slimy layer on the cap surface results from an interwoven layer of gelatinous hypha
e that are typically 3–5 µm thick.
, but opinions about its palatibility are mixed: one author says the fruit bodies are "coarse and do not taste good"; another mentions the "thin flesh hardly make this species worthwhile;" yet another says "The yellow cap may remind you of chicken fat; it has a wonderfully savory mushroom flavor." The slimy texture of the mushroom has been compared to okra
. One cookbook author suggests that the mushroom is ideal for spreads, for use on bread or as a dip; baking the fruit bodies in an oven will dry them for future use, and concentrate the flavor. The odor and taste are mild; one field guide suggests it has a "distinctive lemony tang". The slimy caps and the pore layer are typically removed before consumption.
(distributed in western North America and western and central Asia) but the latter species associates with Pinus monticola and Pinus flexilis rather than Pinus strobus. One field guide suggests that Suillus sibiricus has a thicker stem than S. americanus, brown spots on the cap, and is a darker, more dingy yellow. Molecular phylogenetics analysis has shown, however, that specimens of S. sibricus collected from China and western North America, as well as S. americanus from eastern North America, are most likely "a single circumboreal taxon".
Another lookalike species is Suillus subaureus, which can be distinguished microscopically by slightly smaller, hyaline
(translucent) spores (typically 7.5–8.5 by 3 µm), and an association with Quaking Aspen (Populus tremuloides).
Suillus americanus is a common species, and is found growing solitarily or in clusters on the ground throughout northeastern North America, north to Canada, where it typically fruits in the late summer and autumn. It is also found in Guangdong
, China, an example of a disjunct distribution
. Fruit bodies can often be found in drier weather when other species are not abundant.
Suillus americanus is a mycorrhiza
l species, a mutualistic relationship where the fungus forms a sheath on the surface of the root from which hypha
e extend outward into the soil, and inwards between the cortical
cells with which they interface to form a Hartig net
. The main benefit for the fungus is constant access to a supply of carbohydrate
s produced by the plant's photosynthesis
, while the plant benefits from an enhanced supply of mineral nutrients
from the soil, taken up by the hyphae of the fungus. It grows in association with pines, particularly eastern white pine
(Pinus strobus).
after touching Suillus americanus. The symptoms of allergic contact dermatitis
generally develop one to two days after initial contact, persist for roughly a week, then disappear without treatment. Cooking the fruit bodies inactivates the responsible allergens.
known as a beta glucan that laboratory tests suggest may have anti-inflammatory
activity. Known specifically as a (1→3)-, (1→4)-β-D-glucan, its natural function is as a component of the fungal cell wall
, where it forms microcrystalline fibrils in the wall that give it rigidity and strength. The anti-inflammatory activity results from the polysaccharide's ability to inhibit the production of nitric oxide
in activated macrophage
s, a cell of the immune system
.
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 Suillaceae
Suillaceae
The Suillaceae are a family of fungi in the order Boletales , containing the boletus-like Suillus, the small truffle-like Truncocolumella, as well as the monotypic genus Psiloboletinus. As of 2008, there are 54 species in the family...
family of mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
s. Commonly known as the chicken fat mushroom, the American slippery Jack (or slipperycap), or the American suillus, it grows in a mycorrhizal association with eastern white pine
Eastern White Pine
Pinus strobus, commonly known as the eastern white pine, is a large pine native to eastern North America, occurring from Newfoundland west to Minnesota and southeastern Manitoba, and south along the Appalachian Mountains to the northern edge of Georgia.It is occasionally known as simply white pine,...
and can be found where this tree occurs in eastern North America and China. The mushroom can be recognized by the bright yellow cap
Pileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
with red to reddish-brown scales embedded in slime, the large yellow angular pores on the underside of the cap, and the narrow yellow stem
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...
marked with dark reddish dots. Molecular phylogenetics analysis suggests that S. americanus may be the same species as S. sibiricus
Suillus sibiricus
Suillus sibiricus is a fungus of the genus Suillus in the Suillaceae family. It is found in mountains of Europe, North America and Siberia, strictly associated with several species of pine tree. Due to its specific habitat and rarity in Europe, it has been selected for inclusion in several regional...
, found in western North America and western and central Asia. Suillus americanus is edible
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
, although opinions vary as to its palatability
Palatability
Palatability is the hedonic reward provided by foods or fluids that are agreeable to the "palate" in regard to the homeostatic satisfaction of nutritional, water, or energy needs. The palatability of a food or fluid, unlike its flavor or taste, varies with the state of an individual: it is lower...
; some susceptible individuals may suffer a contact dermatitis
Contact dermatitis
Contact dermatitis is a term for a skin reaction resulting from exposure to allergens or irritants . Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight....
after touching the fruit bodies
Basidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
. The fruit bodies contain a beta glucan carbohydrate 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....
properties.
Taxonomy and classification
Charles Horton Peck
Charles Horton Peck, born March 30, 1833 in Sand Lake, New York, died 1917 in Albany, New York, was an American mycologist of the 19th and early 20th centuries...
in 1888, based on specimens he had originally collected as far back as 1869, in New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
state, near Sand Lake
Sand Lake, New York
Sand Lake is a town in Rensselaer County, New York, United States. As of the 2000 census, the town had a population of 7,987. The Capital District Regional Planning Commission indicates it to be 8,336 as of September 2010. The town is in the south-central part of the county...
, Albany
Albany, New York
Albany is the capital city of the U.S. state of New York, the seat of Albany County, and the central city of New York's Capital District. Roughly north of New York City, Albany sits on the west bank of the Hudson River, about south of its confluence with the Mohawk River...
, and Port Jefferson
Port Jefferson, New York
The Incorporated Village of Port Jefferson is located in the town of Brookhaven in Suffolk County, New York on the North Shore of Long Island. As of the 2000 United States Census, the village population was 7,837...
. In his 1888 publication he indicated that he had originally listed these collections as Boletus flavidus (now known as Suillus flavidus) in his 1869 Report of the State Botanist (published in 1872). However, as was pointed out nearly a century later in 1986, the 1869 report does not actually mention the species; rather, Peck's field notes that year (which served as the basis for the report) reference a collection at Sand Lake upon which the original (1888) description was most likely based. Because Peck failed to designate a type specimen, one of the Sand Lake specimens was lectotypified
Lectotype
In botanical nomenclature and zoological nomenclature, a lectotype is a kind of name-bearing type. When a species was originally described on the basis of a name-bearing type consisting of multiple specimens, one of those may be designated as the lectotype...
in 1986.
In 1931, French mycologist Jean-Edouard Gilbert transferred the species to the genus Ixocomus, a now-defunct taxon that has since been subsumed into Suillus. In 1959, Walter H. Snell
Wally Snell
Walter Henry "Doc" Snell was a pinch-hitter/catcher in Major League Baseball who played briefly for the Boston Red Sox during the season. Following this brief baseball career he became a successful mycologist who worked primarily at Brown University for the next 60 years.-Baseball career:Snell...
, collaborating with Rolf Singer
Rolf Singer
Rolf Singer was a German-born mycologist and one of the most important taxonomists of gilled mushrooms in the 20th century....
and Esther A. Dick, transferred the species to Suillus. In his 1986 version of the authoritative monograph
Monograph
A monograph is a work of writing upon a single subject, usually by a single author.It is often a scholarly essay or learned treatise, and may be released in the manner of a book or journal article. It is by definition a single document that forms a complete text in itself...
The Agaricales in Modern Taxonomy, Singer included the species in the subsection Latiporini of genus Suillus
Suillus
Suillus is a genus of basidiomycete fungi in the family Suillaceae and order Boletales. Species in the genus are associated with coniferous trees, and are mostly distributed in northern temperate locations, although some species have been introduced to the Southern Hemisphere.-Taxonomy:The genus...
, an infrageneric grouping (below the taxonomic
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...
level of genus) characterized by a cinnamon-colored spore print
Spore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
without an olive tinge, and wide pores, typically greater than 1 mm when mature.
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 for the species include the American slipperycap, the American suillus, or the chicken-fat mushroom. The latter name is a reference to its yellow color. The specific epithet americanus means "of America".
Description
The capPileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
is typically between 3 – in diameter, broadly convex with a small umbo (a central elevation) to flat with age. The cap margin is curved inwards in young specimens, and may have remnants of a yellowish, cottony veil hanging from it. The cap surface is colored bright yellow with red or brownish streaks and hairy patches. When the fruit body is young and moist, the surface is slimy; as the cap matures and dries out, it becomes sticky or tacky.
The tubes which comprise the pore layer on the underside of the cap are 0.4 to 0.6 cm (0.15748031496063 to 0.236220472440945 in) deep, and have an adnate (attached broadly to the stem) to decurrent (running down the length of the stem) attachment to the stem. They are yellow, and stain reddish-brown when bruised. The yellow pores are large (1–2 mm diameter) and angular, and tend to become darker as they age. The pores are slightly wider than long, so that there are about 9–10 pores per centimeter measured radially, but 12 to 13 per centimeter when measured tangentially, about halfway to the edge. As is the case with all boletes, 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...
form on the inner surfaces of the tubes and sift through their openings to be borne away on the air currents outside.
The stem
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...
is 3 – by 0.4 –, roughly equal in width throughout, often crooked, and becomes hollow with age. The color of the stem surface is lemon yellow, and it is covered with glandular dots that bruise if handled. The partial veil
Partial veil
thumb|150px|right|Developmental stages of [[Agaricus campestris]] showing the role and evolution of a partial veilPartial veil is a mycological term used to describe a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics...
is not attached to the stem, and usually does not leave an ring
Annulus (mycology)
An annulus is the ring like structure sometimes found on the stipe of some species of mushrooms. The annulus represents the remaining part of the partial veil, after it has ruptured to expose the gills or other spore-producing surface. An annulus may be thick and membranous, or it may be cobweb-like...
on the stem. A whitish mycelium
Mycelium
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...
present at the base of the stem helps anchor the fruit body 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...
. The flesh
Trama (mycology)
In mycology trama is a term for the inner, fleshy portion of a mushroom's basidiocarp, or fruit body. It is distinct from the outer layer of tissue, known as the pileipellis or cuticle, and from the spore-bearing tissue layer known as the hymenium....
is mustard yellow, and stains pinkish-brown when cut or bruised.
Microscopic characteristics
In depositSpore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
, 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 cinnamon-colored. Viewed with a microscope, they are pale yellow, smooth, and roughly elliptical in shape, and measure 8–9.5 by 3.5–5 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 basidia, the spore-bearing cells, are club-shaped and 4-spored, with dimensions of 21–25 by 5.5 to 6 µm. The pleurocystidia (cystidia found on the sides of a gill) range in shape from cylindrical to club-shaped and are arranged in bundles. Both the bases of the bundles and the surface of the cystidia may be covered with brown pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
particles. Cheilocystidia are cystidia located in the gill faces. In S. americanus, they are mostly club-shaped, often with an expanded apex, and like the pleurocystidia, are arranged in bundles, with brown pigment particles at the base of the bundles. Bundles of cystidia near the tube openings may sometimes be visible with a hand lens. Like all Suillus species, the cystidia of S. americanus will turn orange-brown in the presence of a solution of 3% potassium hydroxide
Potassium hydroxide
Potassium hydroxide is an inorganic compound with the formula KOH, commonly called caustic potash.Along with sodium hydroxide , this colorless solid is a prototypical strong base. It has many industrial and niche applications. Most applications exploit its reactivity toward acids and its corrosive...
. The slimy layer on the cap surface results from an interwoven layer of gelatinous 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 typically 3–5 µm thick.
Edibility
This species is edibleEdible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
, but opinions about its palatibility are mixed: one author says the fruit bodies are "coarse and do not taste good"; another mentions the "thin flesh hardly make this species worthwhile;" yet another says "The yellow cap may remind you of chicken fat; it has a wonderfully savory mushroom flavor." The slimy texture of the mushroom has been compared to okra
Okra
Okra is a flowering plant in the mallow family. It is valued for its edible green seed pods. The geographical origin of okra is disputed, with supporters of South Asian, Ethiopian and West African origins...
. One cookbook author suggests that the mushroom is ideal for spreads, for use on bread or as a dip; baking the fruit bodies in an oven will dry them for future use, and concentrate the flavor. The odor and taste are mild; one field guide suggests it has a "distinctive lemony tang". The slimy caps and the pore layer are typically removed before consumption.
Similar species
Suillus americanus is very similar in appearance to Suillus sibiricusSuillus sibiricus
Suillus sibiricus is a fungus of the genus Suillus in the Suillaceae family. It is found in mountains of Europe, North America and Siberia, strictly associated with several species of pine tree. Due to its specific habitat and rarity in Europe, it has been selected for inclusion in several regional...
(distributed in western North America and western and central Asia) but the latter species associates with Pinus monticola and Pinus flexilis rather than Pinus strobus. One field guide suggests that Suillus sibiricus has a thicker stem than S. americanus, brown spots on the cap, and is a darker, more dingy yellow. Molecular phylogenetics analysis has shown, however, that specimens of S. sibricus collected from China and western North America, as well as S. americanus from eastern North America, are most likely "a single circumboreal taxon".
Another lookalike species is Suillus subaureus, which can be distinguished microscopically by slightly smaller, 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) spores (typically 7.5–8.5 by 3 µm), and an association with Quaking Aspen (Populus tremuloides).
Habitat and distribution
Guangdong
Guangdong is a province on the South China Sea coast of the People's Republic of China. The province was previously often written with the alternative English name Kwangtung Province...
, China, an example of a disjunct distribution
Disjunct distribution
In biology, a taxon with a disjunct distribution is one that has two or more groups that are related but widely separated from each other geographically...
. Fruit bodies can often be found in drier weather when other species are not abundant.
Suillus americanus is a mycorrhiza
Mycorrhiza
A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant....
l species, a mutualistic relationship where the fungus forms a sheath on the surface of the root from which 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 extend outward into the soil, and inwards between the cortical
Cortex (botany)
In botany, the cortex is the outer layer of the stem or root of a plant, bounded on the outside by the epidermis and on the inside by the endodermis. It is composed mostly of undifferentiated cells, usually large thin-walled parenchyma cells of the ground tissue system. The outer cortical cells...
cells with which they interface to form a Hartig net
Hartig net
Hartig net is a hyphal network, that extends into the root, penetrating between epidermal and cortical cells. This network is a site of nutrient exchange between the fungus and the host plant...
. The main benefit for the fungus is constant access to a supply of 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 produced by the plant's 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...
, while the plant benefits from an enhanced supply of mineral nutrients
Dietary mineral
Dietary minerals are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen present in common organic molecules. Examples of mineral elements include calcium, magnesium, potassium, sodium, zinc, and iodine...
from the soil, taken up by the hyphae of the fungus. It grows in association with pines, particularly eastern white pine
Eastern White Pine
Pinus strobus, commonly known as the eastern white pine, is a large pine native to eastern North America, occurring from Newfoundland west to Minnesota and southeastern Manitoba, and south along the Appalachian Mountains to the northern edge of Georgia.It is occasionally known as simply white pine,...
(Pinus strobus).
Allergenicity
Some susceptible individuals have experienced an allergic reactionAllergy
An Allergy is a hypersensitivity disorder of the immune system. Allergic reactions occur when a person's immune system reacts to normally harmless substances in the environment. A substance that causes a reaction is called an allergen. These reactions are acquired, predictable, and rapid...
after touching Suillus americanus. The symptoms of allergic contact dermatitis
Contact dermatitis
Contact dermatitis is a term for a skin reaction resulting from exposure to allergens or irritants . Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight....
generally develop one to two days after initial contact, persist for roughly a week, then disappear without treatment. Cooking the fruit bodies inactivates the responsible allergens.
Bioactive compounds
Suillus americanus contains a 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,...
known as a beta glucan that laboratory tests suggest may 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. Known specifically as a (1→3)-, (1→4)-β-D-glucan, its natural function is as a component of the fungal cell wall
Cell wall
The cell wall is the tough, usually flexible but sometimes fairly rigid layer that surrounds some types of cells. It is located outside the cell membrane and provides these cells with structural support and protection, and also acts as a filtering mechanism. A major function of the cell wall is to...
, where it forms microcrystalline fibrils in the wall that give it rigidity and strength. The anti-inflammatory activity results from the polysaccharide's ability to inhibit the production of 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...
in activated 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, a cell of 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...
.