Phallus indusiatus
Encyclopedia
Phallus indusiatus, commonly called in English the bamboo fungus, bamboo pith, long net stinkhorn, crinoline stinkhorn or veiled lady, is a stinkhorn
Stinkhorn
The Phallaceae are a family of fungi, commonly known as stinkhorn mushrooms. Belonging to the fungal order Phallales, the Phallaceae have a worldwide distribution, but are especially prevalent in tropical regions. They are known for their foul smelling sticky spore masses, or gleba, borne on the...

 fungus
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 Phallaceae family. It 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...

 in tropical areas, and has been collected in Asia, the Americas, and Africa. The fungus is characterised by a conical to bell-shaped cap on a stipe
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...

 and a lacy "skirt" that hangs from beneath the cap. Mature fruit bodies
Sporocarp (fungi)
In fungi, the sporocarp is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne...

 are up to 30 cm (12 in) tall with a cap that is 2–4 cm (0.8–1.6 in) long. The cap is covered with a greenish spore-containing slime, which attract flies and other insects that eat the spores and disperse them. It is an edible mushroom
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...

 used as an ingredient in Chinese haute cuisine
Chinese cuisine
Chinese cuisine is any of several styles originating in the regions of China, some of which have become highly popular in other parts of the world – from Asia to the Americas, Australia, Western Europe and Southern Africa...

; the mushroom is grown commercially and commonly sold in Asian markets
Asian supermarket
An Asian supermarket, sometimes called an "Oriental supermarket", is a grocery store in non-Asian countries that stocks items imported from the many countries in East and Southeast Asia. They carry items and ingredients generally well-suited for Asian cuisines and not found in most Western...

. Nutritional analysis has shown that the mushroom is rich in protein, 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 and dietary fiber
Dietary fiber
Dietary fiber, dietary fibre, or sometimes roughage is the indigestible portion of plant foods having two main components:* soluble fiber that is readily fermented in the colon into gases and physiologically active byproducts, and* insoluble fiber that is metabolically inert, absorbing water as it...

. The mushroom also contains various bioactive compounds
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...

, and has 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...

 and antimicrobial
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...

 properties.

Taxonomy and naming

Phallus indusiatus was initially described by French naturalist Étienne Pierre Ventenat
Étienne Pierre Ventenat
Étienne Pierre Ventenat was a French botanist born in Limoges. He was the brother of naturalist Louis Ventenat ....

 in 1798, and sanctioned
Sanctioned name
In mycology, a sanctioned name is a name that was adopted in certain works of Christiaan Hendrik Persoon or Elias Magnus Fries, which are considered major points in fungal taxonomy.-Definition and effects:...

 under that name by Christian Hendrik Persoon
Christian Hendrik Persoon
Christiaan Hendrik Persoon was a mycologist who made additions to Linnaeus' mushroom taxonomy.-Early life:...

 in 1801. One author anonymously gave his impressions of Ventenat's discovery in an 1800 publication:
This beautiful species, which is sufficiently characterised to distinguish it from every other individual of the class, is copiously produced in Dutch Guiana, about 300 paces from the sea, and nearly as far from the left bank of the river of Surinam. It was communicated to me by the elder Vaillant, who discovered it in 1755 on some raised ground which was never overflowed by the highest tides, and is formed of a very fine white sand, covered with a thin stratum of earth. The prodigious quantity of individuals of this species which grow at the same time, the very different periods of their expansion, the brilliancy and the varied shades of their colours, present a prospect truly picturesque.
The fungus was later placed in a new genus, Dictyophora, in 1809 by Desvaux
Nicaise Auguste Desvaux
-Works:*Journal de Botanique, appliquée à l'Agriculture, à la Pharmacie, à la Médecine et aux Arts .*Observations sur les plantes des environs d'Angers ....

; it was then known for many years as Dictyophora indusiata. Christian Gottfried Daniel Nees von Esenbeck
Christian Gottfried Daniel Nees von Esenbeck
Christian Gottfried Daniel Nees von Esenbeck was a prolific German botanist, physician, zoologist, and natural philosopher. He was a contemporary of Goethe and was born within the lifetime of Linnaeus. He described approximately 7,000 plant species...

 placed the species in Hymenophallus in 1817, as H. indusiatus. However, when both Dictyophora and Hymenophallus were variously rendered synonyms of Phallus
Phallus (genus)
The genus Phallus, commonly known as stinkhorns, are a group of basidiomycetes which produce a foul-scented, phallic mushroom, from which their name is derived. The genus has a widespread distribution and, according to a 2008 estimate, contains 18 species. They belong to the family Phallaceae in...

, the species was reclassified under its original name.

Its specific epithet is the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 adjective indūsǐātus "wearing an undergarment". The former generic name Dictyophora is derived from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...

 words diktu- "net", and pherein "to bear", hence "bearing a net". Phallus indusiatus has many 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 based on its appearance, including long net stinkhorn, crinoline stinkhorn, bamboo mushroom, basket stinkhorn, bridal veil fungus, or veiled lady. Its Japanese name is Kinugasatake. Alternate 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 that refer to its typical growth habitat include "bamboo fungus" or "bamboo pith", and its Chinese
Chinese language
The Chinese language is a language or language family consisting of varieties which are mutually intelligible to varying degrees. Originally the indigenous languages spoken by the Han Chinese in China, it forms one of the branches of Sino-Tibetan family of languages...

 name zhu sheng (竹笙, pinyin: zhúshēng) or zhu sun (竹荪; pinyin: zhúsūn).

Description

Immature fruit bodies of P. indusiatus are egg-shaped to roughly spherical, whitish to pale brown, and up to 5 cm (2 in) in diameter. The mature mushroom is up to 30 cm (12 in) tall, and is girded with a net-like structure called the indusium, or "skirt", which hangs down around 15 cm (6 in) from the conical cap. The netlike openings of the indusium may be polyhedral or round in shape. Well-developed specimens have the indusium reaching the volva and flaring out somewhat before collapsing. The bell-shaped cap is 2–4 cm (0.8–1.6 in) high and covered with a greenish-brown slime termed 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...

. The 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...

 is 7–25 cm (3–10 in) high and 0.2–0.5 cm in diameter. The method of reproduction for stinkhorns, including P. indusiatus, is different from many mushrooms, which use the air to spread their 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. Stinkhorns instead produce a sticky spore mass
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...

 on their tip which has a sharp, sickly-sweet odor of carrion
Carrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...

 to attract bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...

s, and flies
Fly
True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...

. The mature fruiting bodies can be smelled from a considerable distance in the woods, and at close quarters most people find the cloying stink extremely repulsive. The flies land in the gleba and consume the slime, depositing it as excrement elsewhere. In older fungi the slime is eventually removed, leaving the pale off-white, bare pitted and ridged surface exposed. The fruit bodies develop during the night, and are short-lived, typically lasting 1–3 days.

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 are thin-walled, smooth, ellipsoid, straight to slightly curved in side view, 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), and measure 2–3 by 1–1.5 μm.

The Argentinian mycologist Jorge Eduardo Wright
Jorge Eduardo Wright
Jorge Eduardo Wright was an Argentinian mycologist. Born in Buenos Aires, he graduated from the University of Buenos Aires in 1949. He was awarded a Latin American Guggenheim Fellowship and studied under Alexander H. Smith at the University of Michigan, under whom he received his Master of Science...

 reported finding specimens in Argentina and Bolivia, otherwise identical to the normal variant, with a pink indusium. He named these Dictyophora indusiata var. rosea.

Similar species

Phallus multicolor is similar in overall appearance, but it has a more brightly colored cap, stem and indusiatum, and it is usually smaller. It is found in Australia, Guam, Sumatra, Java, Borneo, Papua New Guinea, Zaire, and Tobago as well as Hawaii. The cap of the Indo-Pacific species Phallus merulinus appears smooth when covered with gleba, and is pale and wrinkled once the gleba has worn off. In contrast, the cap surface of P. indusiatus tends to have conspicuous reticulations that are not obscured even when covered with gleba. Also, the indusium of P. merulinus is more delicate and shorter than that of P. indusiatus, and thus less likely to collapse under its own weight. P. cinnabarinus, a Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...

ese species found under the bamboo Dendrocalamus latiflorus, grows to 13 cm (5.1 in) tall, and has a more offensive odor than P. indusiatus. It attracts flies from the genus Lucida
Lucida
Lucida is an extended family of related typefaces designed by Charles Bigelow and Kris Holmes in 1985.There are many variants called Lucida, including scripts , serif , and sans-serif .Bigelow & Holmes, together with the TeX vendor Y&Y, extended the Lucida family with a full...

, rather than the house flies of the genus Musca
Musca
Musca is one of the minor southern constellations. The constellation was one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman and it first appeared on a 35-cm diameter celestial globe published in 1597 in Amsterdam by...

that prefer P. indusiatus. P. echinovolvatus, described from China in 1988, is closely related to P. indusiatus, but can be distinguished by its volva which has an echinulate
Echinulate
Echinulate is an adjective describing the spiny, or "spiky" nature of some spores found in plants and fungi; an example is the auxiliary cell. The words derives from the same root as the prefix echino, meaning that the shape is similar to the porcupine ....

 (spiky) surface, and its higher preferred growth temperature of 30 to 35 °C (86 to 95 F).

Distribution and habitat

The range of Phallus indusiatus is tropical, including Africa (Congo, Nigeria, Uganda, and Zaire) South America (Brazil Guyana, and Venezuela), Central America (Costa Rica), and Tobago. In North America, its range is restricted to Mexico. Asian localities include Malaysia, southern China, Japan, and Taiwan. It has also been collected in Australia. Like all Phallus species, the fungus is saprobic—deriving nutrients from breaking down wood and plant organic matter. It tends to grow in disturbed ground and among wood chips. In Asia, it grows among bamboo
Bamboo
Bamboo is a group of perennial evergreens in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Giant bamboos are the largest members of the grass family....

 forests, and is typically found after heavy rains.

Edibility

Previously only collected in the wild, where it is uncommon, P. indusiatus was rare and difficult to procure. The mushroom's rarity meant that it was usually reserved for special occasions. In the time of China's Qing Dynasty
Qing Dynasty
The Qing Dynasty was the last dynasty of China, ruling from 1644 to 1912 with a brief, abortive restoration in 1917. It was preceded by the Ming Dynasty and followed by the Republic of China....

, the species was collected in Yunnan Province and sent to the Imperial Palaces
Forbidden City
The Forbidden City was the Chinese imperial palace from the Ming Dynasty to the end of the Qing Dynasty. It is located in the middle of Beijing, China, and now houses the Palace Museum...

 to satisfy the appetite of Empress Dowager Cixi
Empress Dowager Cixi
Empress Dowager Cixi1 , of the Manchu Yehenara clan, was a powerful and charismatic figure who became the de facto ruler of the Manchu Qing Dynasty in China for 47 years from 1861 to her death in 1908....

, who particularly enjoyed meals with edible fungi. It was one of the eight featured ingredients of the "Bird's Nest Eight Immortals Soup" served at a banquet to celebrate her 60th birthday. Another notable use was a banquet held for Henry Kissinger
Henry Kissinger
Heinz Alfred "Henry" Kissinger is a German-born American academic, political scientist, diplomat, and businessman. He is a recipient of the Nobel Peace Prize. He served as National Security Advisor and later concurrently as Secretary of State in the administrations of Presidents Richard Nixon and...

 on his visit to China to reestablish diplomatic relations in the early 1970s. One source writes of the mushroom: "It has a fine and tender texture, fragrance and is attractive, beautiful in shape, fresh and crispy in taste." The dried fungus, commonly sold in Asian markets
Asian supermarket
An Asian supermarket, sometimes called an "Oriental supermarket", is a grocery store in non-Asian countries that stocks items imported from the many countries in East and Southeast Asia. They carry items and ingredients generally well-suited for Asian cuisines and not found in most Western...

, is prepared by rehydrating and soaking or simmering in water until tender.

Phallus indusiatus has been cultivated on a commercial scale in China since 1979. In the Fujian Province of China—known for a thriving mushroom industry that cultivates 45 species of edible fungi—P. indusiatus is produced in the counties of Fuan, Jianou, and Ningde
Ningde
Ningde , also known as Mindong , is a prefecture-level city located along the northeastern coast of Fujian province, China. It borders Fuzhou to the south, Wenzhou City and Zhejiang province to the north, and Nanping City to the west.-Administration:...

. Advances in cultivation have made the fungus cheaper and more available; in 1998, about 1100 metric tons (1,082.6 LT) were produced in China. The Hong Kong price for a kilogram of dried mushrooms reached around US $770 in 1982, but had dropped to US $100–200 by 1988. Further advances led to it dropping further to US $10–20. The fungus is grown on agricultural wastes—bamboo-trash sawdust covered with a thin layer of non-sterilized soil. The optimal temperature for the growth of mushroom spawn and fruit bodies is about 24 °C (75.2 °F), with a relative humidity
Relative humidity
Relative humidity is a term used to describe the amount of water vapor in a mixture of air and water vapor. It is defined as the partial pressure of water vapor in the air-water mixture, given as a percentage of the saturated vapor pressure under those conditions...

 of 90–95%. Other 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...

 which can be used for the cultivation of the fungus include bamboo leaves and small stems, soybean
Soybean
The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...

 pods or stems, corn stems, and willow
Willow
Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...

 leaves.

Jonathan and colleagues have performed a nutritional analysis of P. indusiatus, based on specimens collected from Nigeria. They determined that the egg stage of the fungus contains (per 100 g of fungus, dry weight
Dry matter
The dry matter is a measurement of the mass of something when completely dried.The dry matter of plant and animal material would be its solids, i.e. all its constituents excluding water. The dry matter of food would include carbohydrates, fats, proteins, vitamins, minerals, and antioxidants...

) 33.6 g of crude protein, 1.66 g of fat
Fat
Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...

, and 3.98 g 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. The egg stage was also measured to comprise 20.9 g crude fiber
Dietary fiber
Dietary fiber, dietary fibre, or sometimes roughage is the indigestible portion of plant foods having two main components:* soluble fiber that is readily fermented in the colon into gases and physiologically active byproducts, and* insoluble fiber that is metabolically inert, absorbing water as it...

, and 88.76% moisture
Water content
Water content or moisture content is the quantity of water contained in a material, such as soil , rock, ceramics, fruit, or wood. Water content is used in a wide range of scientific and technical areas, and is expressed as a ratio, which can range from 0 to the value of the materials' porosity at...

. The high levels of protein and fiber (which are comparable to values found in meat and vegetables, respectively) suggest that the egg form of P. indusiatus is a good food source. The concentration of several mineral elements, including potassium
Potassium
Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...

, sodium
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...

, and iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 was also favorable compared to fruits and vegetables, although the authors mention that mineral
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...

 composition in the fungus is dependent on their corresponding concentrations in the soil in which they grow.

Bioactive compounds

The fruit bodies of the fungus contain biologically active
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...

 polysaccharide
Polysaccharide
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. A β-D-glucan
Beta-glucan
β-Glucans are polysaccharides of D-glucose monomers linked by β-glycosidic bonds. β-glucans are a diverse group of molecules that can vary with respect to molecular mass, solubility, viscosity, and three-dimensional configuration...

 called T-5-N, prepared from alkaline extracts, has been shown 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. The chemical structure of the polysaccharide was found to have a linear chain backbone made largely of α-1→3 linked D-mannopyranosyl residues, with traces of 1→6 linked D-mannopyrosyl residues. The polysaccharide has exhibited tumor-suppressing activity against subcutaneously implanted sarcoma 180 (a transplantable, non-metastasizing
Metastasis
Metastasis, or metastatic disease , is the spread of a disease from one organ or part to another non-adjacent organ or part. It was previously thought that only malignant tumor cells and infections have the capacity to metastasize; however, this is being reconsidered due to new research...

 connective tissue tumor
Tumor
A tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...

 often used in research) in mice.
P. indusiatus contains the chemical 5-(hydroxymethyl)-2-furfural (also known as hydroxymethylfurfural
Hydroxymethylfurfural
Hydroxymethylfurfural , also 5-furfural, is an organic compound derived from dehydration of certain sugars. This yellow low-melting solid is highly water-soluble. The molecule consists of a furan ring, containing both aldehyde and alcohol functional groups...

). This compound inhibits tyrosinase
Tyrosinase
Tyrosinase also known as monophenol monooxygenase is an enzyme that catalyses the oxidation of phenols and is widespread in plants and animals...

, an enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

 that catalyzes the initial steps of melanogenesis in mammals, and is responsible for the undesirable browning reactions in damaged fruits during post-harvest handling and processing. For these reasons, researchers are interested in finding effective tyrosinase inhibitors for the medical, cosmetics, and food industries. Hydroxymethylfurfural occurs naturally in several foods, and is not associated with serious health risks. P. indusiatus also contains a unique ribonuclease
Ribonuclease
Ribonuclease is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within the EC 2.7 and 3.1 classes of enzymes.-Function:All organisms studied contain...

 (RNase)—an enzyme that cuts RNA
RNA
Ribonucleic acid , or RNA, is one of the three major macromolecules that are essential for all known forms of life....

 into smaller components. The enzyme has several biochemical characteristics that differentiate it from other known mushroom RNases: a unique N-terminal sequence of peptides
Peptide sequence
Peptide sequence or amino acid sequence is the order in which amino acid residues, connected by peptide bonds, lie in the chain in peptides and proteins. The sequence is generally reported from the N-terminal end containing free amino group to the C-terminal end containing free carboxyl group...

; an unusual sensitivity to heat
Thermolabile
Thermolabile refers to a substance which is subject to destruction/decomposition or change in response to heat. This term is often used to describe biochemical substances....

, whereby enzyme activity is completely lost after 10 minutes at 100 °C (212 °F); optimal enzyme activity at an acidic pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

 (4–4.5); and specificity towards RNAs containing sequences with continuous stretches of uracil
Uracil
Uracil is one of the four nucleobases in the nucleic acid of RNA that are represented by the letters A, G, C and U. The others are adenine, cytosine, and guanine. In RNA, uracil binds to adenine via two hydrogen bonds. In DNA, the uracil nucleobase is replaced by thymine.Uracil is a common and...

 (polyU) and adenine
Adenine
Adenine is a nucleobase with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate and the cofactors nicotinamide adenine dinucleotide and flavin adenine dinucleotide , and protein synthesis, as a chemical component of DNA...

 (polyA).

Two novel sesquiterpene
Sesquiterpene
Sesquiterpenes are a class of terpenes that consist of three isoprene units and have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be acyclic or contain rings, including many unique combinations...

s have been identified from the fruit bodies of the fungus, named dictyophorine A and B. These compounds are based on the eudesmane skeleton (a common structure found in plant-derived flavors and fragrances), are the first eudesmane 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...

 isolated from fungi. The dictyophorines promote the synthesis of nerve growth factor
Nerve growth factor
Nerve growth factor is a small secreted protein that is important for the growth, maintenance, and survival of certain target neurons . It also functions as a signaling molecule. It is perhaps the prototypical growth factor, in that it is one of the first to be described...

 in astroglial cells. Other similar compounds isolated and identified from the fungus include the quinazoline
Quinazoline
Quinazoline is a compound made up of two fused six-membered simple aromatic rings, a benzene ring and a pyrimidine ring. Its chemical formula is C8H6N2. Quinazoline is yellow and crystalline...

 compounds named dictyoquinazoles A, B and C. These chemicals—belonging to a class of compounds known to be rare in nature—were shown in laboratory tests to have a protective effect on cultured
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,...

 mouse neuron
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...

s that had been exposed to neurotoxin
Neurotoxin
A neurotoxin is a toxin that acts specifically on nerve cells , usually by interacting with membrane proteins such as ion channels. Some sources are more general, and define the effect of neurotoxins as occurring at nerve tissue...

s. A total synthesis
Total synthesis
In organic chemistry, a total synthesis is, in principle, the complete chemical synthesis of complex organic molecules from simpler pieces, usually without the aid of biological processes. In practice, these simpler pieces are commercially available in bulk and semi-bulk quantities, and are often...

 for the dictyoquinazoles was reported in 2007.

Extracts of P. indusiatus have been shown to have both 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...

 and antimicrobial
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...

 properties. Mushroom extracts were tested against a variety of bacteria and fungi pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...

ic to humans, and in some cases had antimicrobial activity comparable to the antibiotics ampicillin
Ampicillin
Ampicillin is a beta-lactam antibiotic that has been used extensively to treat bacterial infections since 1961. Until the introduction of ampicillin by the British company Beecham, penicillin therapies had only been effective against Gram-positive organisms such as staphylococci and streptococci...

, tetracycline, and nystatin
Nystatin
Nystatin is a polyene antifungal medication to which many molds and yeast infections are sensitive, including Candida. Due to its toxicity profile, there are currently no injectable formulations of this drug on the US market...

. The antioxidant effect of the fungus is due to a class of molecules known as polyphenols
Polyphenol antioxidant
A polyphenol antioxidant is a type of antioxidant containing a polyphenolic substructure. Numbering over 4,000 distinct species, many of these compounds have antioxidant activity in vitro but are unlikely to have antioxidant roles in vivo...

; this class of compounds, common in some types of legumes and fruits, plays a role in reducing cellular damage resulting from oxidative stress
Oxidative stress
Oxidative stress represents an imbalance between the production and manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage...

.
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