Morchella esculenta
Encyclopedia
Morchella esculenta, is a species of 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 Morchellaceae
Morchellaceae
The Morchellaceae are a family of ascomycete fungi. According to a standard reference work, the family contains 49 species distributed among 4 genera...

 family of the Ascomycota
Ascomycota
The Ascomycota are a Division/Phylum of the kingdom Fungi, and subkingdom Dikarya. Its members are commonly known as the Sac fungi. They are the largest phylum of Fungi, with over 64,000 species...

. It is one of the most readily recognized of all the 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...

s and highly sought after. Each fruit body
Ascocarp
An ascocarp, or ascoma , is the fruiting body of an ascomycete fungus. It consists of very tightly interwoven hyphae and may contain millions of asci, each of which typically contains eight ascospores...

 begins as a tightly compressed, grayish sponge with lighter ridges, and expands to form a large yellowish sponge with large pits and ridges raised on a large white 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...

. The pitted yellow-brown caps
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...

 measure 2 – broad by 2 – tall, and are fused to the stem at its lower margin, forming a continuous hollow. The pits are rounded and irregularly arranged. The hollow stem is typically 2 – long by 2 – thick, and white to yellow. The fungus fruits under hardwood
Hardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...

s during a short period in the spring, depending on the weather, but it is also associated with old orchards, woods, disturbed grounds and burnt areas. Although a process was reported in 1982 to grow the fruit bodies under controlled conditions, attempts to cultivate the mushroom commercially have only been partially successful.

Taxonomy and naming

The fungus was originally named Phallus esculentus by Carl Linnaeus in his Species Plantarum
Species Plantarum
Species Plantarum was first published in 1753, as a two-volume work by Carl Linnaeus. Its prime importance is perhaps that it is the primary starting point of plant nomenclature as it exists today. This means that the first names to be considered validly published in botany are those that appear...

 (1753), and given its current name by Swedish mycologist Elias Magnus Fries
Elias Magnus Fries
-External links:*, Authors of fungal names, Mushroom, the Journal of Wild Mushrooming.*...

 in 1801.

Morchella esculenta is commonly
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...

 known by various names: morel, common morel, true morel, morel mushroom, yellow morel, sponge morel, Molly Moocher, haystack, and dryland fish. In Nepal
Nepal
Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...

 it is known as Guchi chyau. The specific epithet is derived from 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...

 esculenta, meaning "edible".

Description

The 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...

 is pale brownish cream, yellow to tan or pale brown to grayish brown. The edges of the ridges are usually not darker than the pits, and somewhat oval in outline, sometimes bluntly cone-shaped with a rounded top or more elongate. Caps are hollow, and attached to the stem at the lower edge, and typically about 2 – broad by 2 – tall. 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 brittle. 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 white to pallid or pale yellow, hollow, and straight or with a club-shaped or bulbous base. It is finely granular overall, somewhat ridged, generally about 2 – long by 2 – thick. In age it may have brownish stains near the base.

Microscopic characteristics

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 range from white to cream to slightly yellow in deposit, although a 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...

 may be difficult to obtain given the shape of the fruit body. The spores are formed in asci
Ascus
An ascus is the sexual spore-bearing cell produced in ascomycete fungi. On average, asci normally contain eight ascospores, produced by a meiotic cell division followed, in most species, by a mitotic cell division. However, asci in some genera or species can number one , two, four, or multiples...

 lining the pits—the ridges are sterile. They are ellipsoidal, smooth, thin-walled, translucent (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...

), and measure 17.5–21.9 by 8.8–11.0 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 asci
Ascus
An ascus is the sexual spore-bearing cell produced in ascomycete fungi. On average, asci normally contain eight ascospores, produced by a meiotic cell division followed, in most species, by a mitotic cell division. However, asci in some genera or species can number one , two, four, or multiples...

 are eight-spored, 223–300 by 19–20 µm, cylindrical, and hyaline. The paraphyses
Paraphyses
Paraphyses are part of the fertile spore-bearing layer in certain fungi. More specifically, paraphyses are sterile filamentous hyphal end cells composing part of the hymenium of Ascomycota and Basidiomycota interspersed among either the asci or basidia respectively, and not sufficiently...

 are filamentous, cylindrical, 5.8–8.8 µm wide, and hyaline.

The 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 of the stem are interwoven, hyaline, and measure 5.8–9.4 µm wide. The surface hyphae are inflated, spherical to pear-shaped, 22–44 µm wide, covered by a network of interwoven hyphae 11–16.8 µm wide with recurved cylindrical hyphal ends.

Development

Fruit bodies have successfully been grown in the laboratory. R. Ower was the first to described the developmental stages of ascomata grown in a controlled chamber. This was followed by in-depth cytological studies by Thomas Volk and Leonard (1989, 1990). To study the morel life cycle they followed the development of ascoma fruiting in association with tuberous begonias (Begonia tuberhybrida), from very small primordia to fully developed fruit bodies.

Young fruit bodies begin development in the form of a dense knot of hyphae, when suitable conditions of moisture and nutrient availability conditions have been reached. Hyphal knots are underground and cup-shaped for some time, but later emerge from the soil and develop into a stalked fruiting body. Further growth makes the 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...

 convex with the asci
Ascus
An ascus is the sexual spore-bearing cell produced in ascomycete fungi. On average, asci normally contain eight ascospores, produced by a meiotic cell division followed, in most species, by a mitotic cell division. However, asci in some genera or species can number one , two, four, or multiples...

 facing towards the outer side. Because of the unequal growth of the surface of the hymenium, it becomes folded to form many ridges and depressions, resulting in the sponge or honeycomb appearance.

Similar species

Morchella esculenta is probably the most popular of the morels. In contrast to M. angusticeps and its relatives, the caps are light-colored throughout development, especially the ridges, which remain paler than the pits. M. crassipes is sometimes confused with M. esculenta. According to Smith (1975), the two are distinct, but young forms of M. crassipes are difficult to separate from M. esculenta. The two are similar in color, but M. crassipes is larger, often has thin ridges, and sometimes has a stem base that is enlarged and longitudinally grooved.

Morels have also been confused with stinkhorns, but specimens of the latter have a volva
Volva (mycology)
The volva is a mycological term to describe a cup-like structure at the base of a mushroom that is a remnant of the universal veil. This macrofeature is important in wild mushroom identification due to it being an easily observed, taxonomically significant feature which frequently signifies a...

 at the base of the stem, are covered with 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...

—a slimy, foul-smelling spore mass.

Habitat and distribution

Fruit bodies are sometimes found solitary, but more often in groups, on the ground in a variety of habitats. A preference for soil with a limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

 base (alkaline) has been noted, but they have also been found in acid soils
Soil pH
The soil pH is a measure of the acidity or basicity in soils. pH is defined as the negative logarithm of the activity of hydrogen ions in solution. It ranges from 0 to 14, with 7 being neutral. A pH below 7 is acidic and above 7 is basic. Soil pH is considered a master variable in soils as it...

.
The mushroom is usually found in early spring, in forests, orchards, yards, gardens and sometimes in recently burned areas. In North America, it is sometimes referred to as the "May mushroom" due to its consistent fruiting in that month, but the time of fruiting varies locally, from February to July. It is typically the last morel species to fruit in locales where more than one species are found. For example, in Northern Canada and in cooler mountainous regions, morels typically do not appear until June. It has been suggested that the springtime fruiting may be due to their ability to grow at low temperatures to the exclusion of competition, a conclusion later corroborated by experiments correlating spore germination
Germination
Germination is the process in which a plant or fungus emerges from a seed or spore, respectively, and begins growth. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. However the growth of a sporeling from a spore, for example the...

 to soil temperatures.

One author suggests the acronym PETSBASH may be used to remember the trees associated with morels: 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:...

, elm
Elm
Elms are deciduous and semi-deciduous trees comprising the genus Ulmus in the plant family Ulmaceae. The dozens of species are found in temperate and tropical-montane regions of North America and Eurasia, ranging southward into Indonesia. Elms are components of many kinds of natural forests...

, tulip
Liriodendron
Liriodendron is a genus of two species of characteristically large deciduous trees in the magnolia family .These trees are widely known by the common name tulip tree or tuliptree for their large flowers superficially resembling tulips, but are closely related to magnolias rather than lilies, the...

, sassafras
Sassafras
Sassafras is a genus of three extant and one extinct species of deciduous trees in the family Lauraceae, native to eastern North America and eastern Asia.-Overview:...

, beech
Beech
Beech is a genus of ten species of deciduous trees in the family Fagaceae, native to temperate Europe, Asia and North America.-Habit:...

, ash, sycamore
Sycamore
Sycamore is a name which is applied at various times and places to three very different types of trees, but with somewhat similar leaf forms....

, and hickory
Hickory
Trees in the genus Carya are commonly known as hickory, derived from the Powhatan language of Virginia. The genus includes 17–19 species of deciduous trees with pinnately compound leaves and big nuts...

.

In North America, it is widely distributed, but especially common in eastern North America and the Midwest. David Arora
David Arora
David Arora is an American mycologist, naturalist, and writer. He is the author of two popular books on mushroom identification, Mushrooms Demystified and All That the Rain Promises and More.......

 notes that "large crops can also be found around the bases of dying (but not quite dead) elms attacked by Dutch elm disease." The species has been named state mushroom of Minnesota
Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...

, and was the first state mushroom of any state.

Brazil

Cultivation

Due to the mushroom's prized fruit bodies, several attempts have been made to grow the fungus in culture. In 1901, Repin reported successfully obtaining fruit bodies in a cave in which cultures had been established in flower pots nine years previously in 1892.

Edibility

Morchella esculenta, like all morels, are among the most highly-prized of all 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...

s. Raw mushrooms have a gastrointestinal irritant, but parboil
Parboil
Parboiling is the partial boiling of food as the first step in the cooking process.The word is often used when referring to parboiled rice. Parboiling can also be used for removing poisonous or foul-tasting substances from foodstuffs...

ing or blanching before consumption will remove it. Old fruit bodies that show signs of decay may be poisonous. The mushrooms may be fried in butter or baked after being stuffed with meats and vegetables. The mushrooms may also be dried by threading the caps onto string and hanging them in the sun; this process is said to concentrate the flavor. One study determined the main nutritional components to be as follows (on a 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...

 basis): protein 32.7%, 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...

 2.0%, 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...

 17.6%, ash
Ash (analytical chemistry)
In analytical chemistry, ashing is the process of mineralization for preconcentration of trace substances prior to chemical analysis. Ash is the name given to all non-aqueous residue that remains after a sample is burned, and consist mostly of metal oxides....

 9.7%, and 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 38.0%.

In one isolated case in Germany, six people were reported to have developed neurologic effects between 6–12 hours after consumption. The effects included ataxia
Ataxia
Ataxia is a neurological sign and symptom that consists of gross lack of coordination of muscle movements. Ataxia is a non-specific clinical manifestation implying dysfunction of the parts of the nervous system that coordinate movement, such as the cerebellum...

 and visual disturbances, and lasted up to a day before disappearing without enduring effects.

Bioactive compounds

Both the fruit bodies and the mycelia of M. esculenta contain an uncommon amino acid
Amino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...

, cis-3-amino-L-proline; this amino acid does not appear to be protein bound. In addition to M. esculento, the amino acid is known to exist only in M. conica
Morchella conica
Morchella conica is a species of fungus in the Morchellaceae family. It is one of three related species commonly known as the black morel, the others being M. angusticeps and M. elata. It was first described by mycologist Christian Hendrik Persoon in 1818....

 and M. crassipes.

Medicinal properties

Laboratory experiments using rodent models suggest that the 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 from M. esculenta fruit bodies have several medicinal properties, including anti-tumor effects, immunoregulatory
Immunomodulator
An immunomodulator, also known as an immunotherapy is a substance which has an effect on the immune system.- Immunosuppressants :Inhibits immune response in organ transplantation and autoimmune diseases.- Immunostimulants :...

 properties, fatigue resistance, and antiviral effects. Extracts from the fruit bodies have 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...

 properties. It also has been shown that the polysaccharides from M. esculenta mycelia have 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. The fungus is listed in the IUCN National Register of medicinal plants in Nepal.

Morchella esculenta is also used in traditional Chinese medicine
Traditional 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...

 to treat indigestion, excessive phlegm
Phlegm
Phlegm is a liquid secreted by the mucous membranes of mammalians. Its definition is limited to the mucus produced by the respiratory system, excluding that from the nasal passages, and particularly that which is expelled by coughing . Phlegm is in essence a water-based gel consisting of...

, and shortness of breath.

Industrial applications; solid state-fermentation

Solid-state fermentation (SSF) is an industrial process to produce 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...

s and to upgrade the values of existing foods, especially oriental foods. SSF is a process whereby an insoluble substrate is fermented with sufficient moisture but without free water. SSF, unlike that of slurry state, requires no complex fermentation controls and has many advantages over submerged liquid fermentation. M. esculenta has shown promise in degrading starch
Starch
Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...

 and upgrading the nutritional value of cornmeal during SSF.

M. esculenta mycelia is able to bind to and inhibit the effects of Furanocoumarin
Furanocoumarin
Furanocoumarins, or furocoumarins, are a class of organic chemical compounds produced by a variety of plants. They are biosynthesized partly through the phenylpropanoid pathway and the mevalonate pathway, which is biosynthesized by a coupling of dimethylallyl pyrophosphate and 7-hydroxycoumarin...

s, chemicals found in grapefruit
Grapefruit
The grapefruit , is a subtropical citrus tree known for its sour fruit, an 18th-century hybrid first bred in Barbados. When found, it was named the "forbidden fruit"; it has also been misidentified with the pomelo or shaddock , one of the parents of this hybrid, the other being sweet orange The...

 that inhibit human cytochrome p450 enzymes and are responsible for the "grapefruit/drug" interaction phenomenon.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK