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Fungi provide essential support for all communities of multicellular organisms. Fungi recycle the biomass of wood and leaves, including substances such as lignin, which other organisms may not be able to digest ^[1]. Underground fungal filaments called mycorrhizae extend the root systems of most plants, which form network, that interconnect that plant community.Fungi are capable of fermenting plant material, as well as being pathogenic to both plant and animal species. ^[1].

At the tip of a fungal hypha, the cell membrane expands by incorporating vesicles, which are generated by the endoplasmic reticulum. When the vesicle fuses, it provides phospholipids and proteins to extend its membrane surface area, which allows the cytoplasm to expand rapidly ^[1]. The absorption zone for hypha is right behind its tip. The absorption zone takes in nutrients from the neighboring medium. It is also important to notice that, behind the absorption zone, the older part of the hypha collect and stores nutrition as well ^[1]. There is an extensive number of fungal species, with each species differing in form, from the common mushrooms, fruiting bodies that can weigh several pounds, to the mycelia of pathogens and the symbiotic partners of algae in lichens. ^[1].

Fungi have four major phyla; such phylum includes Basidiomycota, Zygomycota, Ascomycota and Chytridiomycota.

Basidiomycetes have cells that are paired nuclei and form mushrooms. They are well known for their exceptional size and diversity of above ground fruiting bodies known as “true” mushrooms ^[1]. Mushrooms offer a flavorful source of protein and minerals, albeit at the risk of consuming the deadly toxins, which are produced by some species. The protein content of edible mushrooms can be as high as 25% dry weight, similar to that of whole milk (per dry weight), and includes all essential dietary amino acids ^[1].

It is important to note there are also Poisonous and Hallucinogenic Fungi which produce deadly poisons such as alpha-amanitin, which inhibits RNA polymerase 2. Alph-amanitin is produced by Amanita, known as “Destroying Angel”; its taste is often fatal. Other mushrooms include Portobello, which is one of the more priced mushrooms around the world ^[1]. Different types of mushrooms grow in different season, some grow in soil, while others such as Piptoporus grows on tree bark.

1 Mycophagy Throughout History
2 Commercial Fungi Production
3 “Chicken-of-the-Woods”
4 Morchella esculenta The Common Morel
5 Coprinus comatus "Shaggy Mane Mushroom"
6 Pleurotus ostreatus – “Oyster mushroom”
7 Agaricus brunnescens - Commercially Harvested Fungi
8 Truffles
9 Notes and References

Mycophagy Throughout History

A Roman floor mosaic depicting picked edible mushrooms in a decorative bowl

Ancient Times

Fungi has been used as a food source by humans for millenia. Archaeological records show edible mushroom fossils along with humans who lived approximately 13000 years ago in what is now modern day Chile ^[2]. A more thorough record of mushrooms as a food source can be dated back to texts written during the Han Dynasty in ancient China (206 BCE-220 CE). In ancient societies around the globe, fungi was not only prized for its medicinal properties, but it was also believed to have magical properties associated with immortality.

Emperor Wu of the Han dynasty went so far as to call for large expeditions to attempt to find these elusive mythological Fungi ^[3]. Fungi shared this mythical status in ancient Egypt. Hieroglyphic depictions of fungi dating back to 4500 BCE can be seen throughout the area. They can even be found in the Book of the Dead where they are described as being the "food of the Gods" ^[4]. The Pharaohs explicitly outlawed the consumption of fungi amongst the common populous as they were seen as only fit for royal consumption ^[5].

Antiquity

In Ancient Greek and Roman times, the mushroom was also a highly prized and was mainly consumed by the upper class. A particular favourite of the Emperors of Rome was the Amanite caesarea or Caesar's Mushroom, regularly on the menu at grand feasts. Unfortunately, its strong resemblance to poisonous varieties made it a relatively common and effective means of assassination. The poison's symptoms would manifest the following day and the victim would die in a week's time ^[6].

Mesoamerica

Of the few Mayan texts which survived the arrival of the Spanish Conquistadors, there are hieroglyphics depicting what appears to be a man outstretching an offering of a mushroom to some sort of Deity. This suggests that mushrooms were integral to religious ceremony amongst the ancient Mayan peoples ^[7].

Mayan deities holding mushrooms

Beginnings of Commercialization

Fungi was first intentionally grown as a crop around 600 CE. In the seventeenth century, mushrooms were first cultivated by the addition of spore laden manure into fresh piles of manure. In 1886 the first sterile techniques were used in order to ensure that only the desired fungi would grow on the substrate. In 1905, it was first discovered that one could produce fungi directly from tissues and not from spores themselves. These discoveries along with the prospects of indoor mushroom production paved the way for the manufacturing techniques used today for mass production ^[8].

Commercial Fungi Production

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“Chicken-of-the-Woods”

(a.k.a Laetiporus conifericola, Laetiporus sulphurous, sulphur shelf)

The texture of cooked pieces is similar to that of chicken, thus the name. ^[9]

Morphology

Chicken-of-the-woods is a widespread and common fungus. It is rich yellow to orange in colour, which fades over time. It is commonly referred to as bracket-fungi due to its shape and shelf-like growth. Fruiting bodies can form up to 30 cm across. They are described to have a smooth, but uneven surface, with a tough, leathery texture.^[10] The underside of the fungi has a stippled appearance because it is lined with a series of tubes where its spores (3-5 per mm) are released. ^[10]

Habitat

‘Chicken-of-the-woods’ is commonly found fruiting on living trees, logs or stumps. They are commonly found of conifers and hardwoods across North America. ^[9]

Edibility

Edible margins, found to cause gasrointestinal upsets in some individuals. ^[9] Finding and cooking 'chicken-of-the-woods'

Morchella esculenta The Common Morel

Kingdom: Fungi
Phylum: Ascomycota
Class: Pezizomycetes
Order: Pezizales
Family: Morchellaceae
Genus: Morchella
Species: esculenta

Brief Description

Morchella esculenta, (commonly known as common morel, morel, yellow morel, true morel, morel mushroom, and sponge morel) is a species of fungus in the Morchellaceae family of the Ascomycota.

Morchella, the true morels, is a genus of edible mushrooms closely related to anatomically simpler cup fungi. These distinctive mushrooms appear honeycomb-like in that the upper portion is composed of a network of ridges with pits between them.

The species has been named state mushroom of Minnesota, and was the first state mushroom of any state.[122][123]

Morels (Morchella spp.) are prized wild edible mushrooms. In the United States, morels are the focus of family traditions, local festivals, mycological society forays, and social media, as well as substantial commercial trade. A majority of the anglophone research on morels has been conducted in Europe and in the U.S. Pacific Northwest and Midwest. This literature provides insights into a diverse and plastic genus, but much of its biology and ecology remains a mystery. [207]

Morels can grown in urban gardens. [235]

Morels and truffles differ widely in their form and behaviour. The morels resemble mushrooms to the extent that they have a cap borne upon a central stem, whilst the truffles form solid, round balls, which grow underground. These are the edible ascomycetes. Both morels and truffles represent some of the most highly prized edible mushrooms in the world. The morels are sometimes referred to as the ‘truffles of the north’, but other popular names include ‘sponge’, ‘pine cone’, ‘corncob’, and ‘honeycomb mushroom’. They are the most popular of the springtime, edible fungi, usually occurring from late March through to mid-June, although each crop will survive only for a several days. Morels have a delicate flavour that can be overwhelmed during cooking, but delicious when eaten alone. They are normally prepared by frying in butter and can be preserved, with drying being the most popular method.

There are two kinds of morel. The true morels belonging to the genus Morchella, and the false morels or lorchels belonging to the genus Helvella. Lorchels can cause serious poisonings and should be avoided. True morels may be classified into two groups. There are the black morels, with dark to deep grey or black ridges at maturity, such as Morchella conica and Morchella elata. These usually appear slightly earlier, and are usually associated with cedar, pines, burnt areas, occasionally on dunes and in the coastal depressions between dunes.

There are a number of varieties, varying in shape and colour, sometimes regarded as separate species, ranging from yellow, with a large round head (var. rigida); ochre-yellow and small (var. rotunda); grayish brown to ochre yellow, with a rounded to conical head (var. vulgaris); blackish brown, with a rounded to conical head (var. umbrina). These occur in mixed hardwoods, especially beech, maple, old apple trees or stumps, and around dead elm trees. In the UK, morels have shown a noticeable increase in their distribution in urban areas over recent years. This is attributed to the increasing use of bark mulch in gardens. They have never been successfully cultivated until very recently and only with limited success. Attempts at cultivation in North America have involved the use of sterile masses of mycelium, or sclerotia, which are enriched by placing them on a layer of wheat or rye grain. These sclerotia are then harvested and distributed on a mixed bark and soil layer to produce the fruit bodies. However, so far the fruiting body yield has been poor, and the small size has yet to be overcome. [238]

Taxonomy and Systematics

Genus Morchella is derived from morchel, an old German word for mushroom, while morel itself is derived from the Latin maurus meaning brown [].

The fungus was originally named Phallus esculentus by Carl Linnaeus in his Species Plantarum (1753),[101] and given its current name by Swedish mycologist Elias Magnus Fries in 1801.[102][103]

The fruiting bodies of the Morchella are highly polymorphic in appearance, exhibiting variations in shape, color and size; this has contributed to uncertainties regarding taxonomy.^[11] Discriminating between the various species is complicated by uncertainty regarding which species are truly biologically distinct. Some authors suggest that the genus only contains as few as 3 to 6 species,[2][3] while others place up to 50 species in the genus.^[12]^[13] Mushroom hunters refer to them by their color (e.g., gray, yellow, black) as the species are very similar in appearance and vary considerably within species and age of individual. The best known morels are the "yellow morel" or "common morel" (M. esculenta); the "white morel" (M. deliciosa); and the "black morel" (M. elata). Other species of true morels include M. conica, M. vulgaris, and the half-free morel (M. semilibera).[]

Each fruit body 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. The pitted yellow-brown caps measure 2–7 cm (0.8–2.8 in) broad by 2–10 cm (0.8–3.9 in) 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 2–9 cm (0.8–3.5 in) long by 2–5 cm (0.8–2.0 in) thick, and white to yellow [].

Phylogeny

Development

Anatomy and Distinguishing Characteristics

Life Cycle

Similar and Related Species

False Morels

Habitat and Distribution

Ecology

Cultivation

Uses

Edibility and Nutrient Composition

Medicinal Properties

Toxicity

Morels contain small amounts of hydrazine[29] toxins that are removed by thorough cooking; morel mushrooms should never be eaten raw.[30] It has been reported that even cooked morels can sometimes cause mild intoxication symptoms when consumed with alcohol.^[14] When eating this mushroom for the first time it is wise to consume a small amount to minimize any allergic reaction. Morels for consumption must be clean and free of decay. Morels growing in old apple orchards that had been treated with the insecticide lead arsenate may accumulate levels of toxic lead and arsenic that are unhealthy for human consumption.^[15]

Raw mushrooms have a gastrointestinal irritant, but parboiling or blanching before consumption will remove it. Old fruit bodies that show signs of decay may be poisonous.^[16]

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 and visual disturbances, and lasted up to a day before disappearing without enduring effects.^[17]

Morchella esculenta and Morchella conica are well known edible morels, which seldom induce clinical symptoms. We report six persons who developed cerebellar effects 6–12 hours after consumption of these mushrooms. The symptoms were self-limited and disappeared after one day [239]Pfab_etal_31291245.pdf

Several cases of (true) morel poisoning associated with neurological symptoms have been reported. Morels are edible mushrooms, which can be toxic when poorly cooked. This retrospective study confirms that morel ingestion may cause a NS. The neurological effects are probably toxic, as they generally occur after ingestion of large amounts. The nature of the toxin and the exact mechanism of its action are still unknown and require further analytical studies as well as experimental studies in animals. [242]Saviuc_etal_50947117.pdf