Hericium erinaceus

Both the Latin genus name and the species name mean 'hedgehog' in Latin. This is also reflected by the German name, (literally, hedgehog-goatee), and some of its common English names, such as bearded hedgehog and hedgehog mushroom. It is known in Japan as (Kanji: , Katakana: ) in reference to the yamabushi or mountain ascetics of the syncretistic religion known as Shugendo; while in Chinese, it is known as () meaning "monkey-head mushroom", in Korea as noru gungdeng-i beoseot () meaning "deer butt mushroom", and in Europe and the United States as ''lion's mane''. == Description ==

The fruit bodies of H. erinaceus are large, irregular bulbous tubercules. They are in diameter and dominated by crowded, hanging, spore-producing spines, which are long or longer. The hyphal system is monomitic, amyloid, and composed of thin- to thick-walled hyphae that are approximately 3–15 μm (microns) wide. The hyphae also contain clamped septa and gloeoplerous elements (filled with oily, resinous substances), which can come into the hymenium as gloeocystidia. The basidia are 25–40 μm long and 5–7 μm wide, contain four spores each and possess a basal clamp. The white amyloid spores measure approximately 5–7 μm in length and 4–5 μm in width. The spore shape is described as subglobose to short ellipsoid and the spore surface is smooth to finely roughened. The monokaryotic mycelium growth of H. erinaceus is slower than dikaryotic growth and only a relatively low percentage of monokaryotic cultures yield fruit bodies. Monokaryotic fruit bodies are also smaller than dikaryotic fruit bodies. Mycochemistry H. erinaceus contains diverse chemicals, including polysaccharides, such as β-glucan, as well as hericenones and erinacines. Low concentrations of ergosterol are present. Additional species with a resemblance include Donkia pulcherrima, Radulomyces copelandii and some within Sarcodontia. == Distribution and habitat ==

In Europe, the fruit bodies of H. erinaceus are mainly produced annually from August to November. In North America, they appear from October to February in the west, from July to October in the Mountain states, and from September to February in the east. It has been described as a symbiotic associate of host trees, possibly occupying an endophytic habitat. H. erinaceus hosts in North America include maple, ash, oaks, and eucalyptus. == Ecology ==

Disease Brennandania lambi (Acari: Pygmephoroidea) is a mite pest of fungi culture in China. This mite can develop and reproduce on the mycelium of H. erinaceus. Farm hygiene and heat treatments are the most important pest management strategies that should be followed to counter this acarus. Competition with other fungi Hericium species are good competitors against other wood colonisers. They show the ability to maintain their place on dead wood, also when confronted with secondary colonizers, such as Trametes versicolor and Stereum hirsutum. == Conservation ==

Although H. erinaceus is native to Europe, it has been red listed in several European countries due to poor germination and establishment. == Cultivation ==

In fungi cultivation, fungal strains are analogous to plant varieties in crop breeding. The production of H. erinaceus is widespread in Asia, mostly using extensive production practices on wood logs or stumps. In North America, its production occurs only on a small scale. Most of it is intensive indoor production with only a few small outdoor sites where log cultivation is practiced. Many different substrates have been used to successfully cultivate this mushroom. Depending on the type of cultivation, the substrate can be either solid (artificial log) or liquid (submerged culture and deep submerged culture). The solid substrate is most commonly a mixture of sawdust of hardwood or conifer containing different complements that may include wheat bran, wheat straw, soybean meal, corn meal, rice bran, and rice straw. For example, H. erinaceus strains grow on beech sawdust substrate enriched with wheat bran (20%), rye grain (25%), soybean meal (7%), rapeseed meal (10%), or meat-osseous flour (6%). Climate requirements Hericium erinaceus requires a humid environment for its growth: 85 to 90% of relative humidity in the air. Submerged fermentation is preferable for the production of mycelial biomass and biologically active metabolites in order to produce a more uniform biomass and extract products. Growth regulators, such as 2,4-Dichlorophenoxyacetic acid and gibberellin, were observed to have an advantageous effect on spore germination. Other technologies, such as red and green laser light of low intensity, stimulated spore germination as well as the vegetative growth of mycelium. Argon and helium lasers also contributed to the acceleration of fruit body development by 36–51%. Wild strains Wild strains of Hericium spp. can be isolated and cultivated by first gathering fruiting bodies from fallen trees in the natural habitat. The fruiting bodies can then be opened to attain pieces of their inner spore-producing tissue. This tissue is then placed onto Petri dishes with agar to cultivate fungal colonies at 25 °C. After several transfers to new Petri dishes to verify the purity of the strain, it can be kept at −80 °C for long-term storage. ==Uses==

Culinary with grilled H. erinaceus The edible fruiting bodies are common in gourmet cooking, with young specimens considered the best. Alongside shiitake (Lentinus edodes) and oyster (Pleurotus ostreatus) mushrooms, H. erinaceus is used as a specialty mushroom in recipes. H. erinaceus fruiting bodies contain 57% carbohydrates (8% as dietary fiber), 4% fat, and 22% protein. Traditional and contemporary uses Used in traditional Chinese medicine for centuries, H. erinaceus is commonly marketed as a dietary supplement for its purported benefits to memory, but lacks sufficient scientific evidence for safety or effectiveness, and quality can vary due to inconsistent processing and labeling. Though it is a generally safe edible mushroom, its efficacy and specific active compounds remain unconfirmed in vivo. ==See also==