Armillaria ostoyae: The Ultimate Mushroom Guide
About The Armillaria ostoyae Mushroom
Armillaria ostoyae (Romagn) also known as honey mushroom an edible mushroom.
Broadly attached to the stem or beginning to run down it; close or nearly distant; short-gills frequent; white or whitish when young and fresh, developing pinkish hues and/or reddish brown spots and discolorations.
5–10 cm long; 0.5–1.5 cm thick; more or less equal, or slightly tapered to base; whitish, becoming brownish to gray or nearly black toward the base; finely hairy with brownish fibrils; with a well-developed whitish ring that may feature a yellowish or brownish underside or edge; usually with yellowish mycelium near the base; attached to long black rhizomorphs that run through the wood.
Whitish, sometimes becoming pinkish-brown with maturity; often yellow in the stem base; unchanging when sliced.
Armillaria ostoyae, is a conifer specific pathogen widespread in the European/Eurasian temperate forests. Its continuous colony covers 3.4 square miles.
Armillaria ostoyae is restricted to European/Eurasian forests, whereas in North America the species should be named A. solidipes. The genome of both species have been sequenced and show substantial differences, undepinning their separation. The diploid individuals of A. ostoyae, spreading very effciently by shoestring like mycelial structures, rhizomorphs, often form large colonies in the soil and have access to the roots of potential hosts in extended areas.
This mushroom is a facultative necrotroph with isolates exhibiting a significant diversity in virulence. After the infection through root contacts, they often cause unseen root and stem rot or they may advance under the bark by invading and killing the cambium of the host.
Very common in most areas, particularly where the soil is acidic, this fungus occurs throughout Britain and Ireland as well as mainland Europe, parts of Asia and in North America. Armillaria species are also present in Australia and New Zealand.
Honey Fungi are long-lived, not as mushrooms but as fine interwoven hyphal threads called mycelia, living and within the soil and feeding on living or dead wood. In suitable habitats, an underground mycelium can grow continually for many hundreds and perhaps even thousands of years.
For example in 1992 an expanding filled-in fairy ring of Armillaria ostoyae was in Washington state was found covering an area of some 1,500 acres; it was declared at the time to be the world's largest known living organism.
Many other forest sites are known to be home to large and therefore ancient Honey Fungus mycelium - indeed in 2000 a 'humungus fungus' was found in Malheur National Forest, in eastern Oregon. Again it was a Dark Honey Fungus. This mycelium, which covered some 2200 acres (800 hectares) and extended into the soil for a depth of three meters, was estimated to be about 2400 years old (DNA analysis showed that the fruitbodies springing up from this vast site were indeed from a single organism rather than several different mycelia).
Armillaria ostoyae Health Benefits
Rich in Antioxidants
Honey fungus mushroom is a great source of antioxidants, which are compounds that help neutralize disease-causing free radicals and protect against chronic disease. In fact, in vitro studies show that several specific compounds isolated from honey mushrooms can be effective at scavenging free radicals and preventing oxidative damage to cells.
Could Help Fight Cancer Cell Growth
While more research is still needed to determine how honey mushrooms may affect cancer in humans, some studies show that it could help block the growth and spread of cancer cells in vitro.
For example, one in vitro study found that armillarikin, a compound found in Armillaria mellea, was able to kill off liver cancer cells. Meanwhile, other research shows that it could even be therapeutic against leukemia and esophageal cancer cells as well.
Protects Brain Health
One of the most promising uses for the honey mushroom medicinal properties is its potential to enhance brain function and protect against neurodegenerative disorders.
One animal model in Oxidative Medicine and Cellular Longevity found that extracts obtained from Armillaria mellea were effective at improving neuron function, preventing cell damage and decreasing the buildup of proteins in the brain that have been linked to Alzheimer’s disease.
May Stabilize Blood Sugar
High blood sugar can come with serious consequences, ranging from impaired headaches and increased thirst to impaired wound healing and vision problems.
According to one 2015 in vitro study, Armillaria mellea extracts exhibited powerful antioxidant and blood-sugar-lowering properties, suggesting that they could be used to develop dietary supplements and pharmaceutical products aimed at treating diabetes.
Versatile and Delicious
Besides their many health benefits, honey mushrooms are tasty, versatile and easy to enjoy in many different recipes.
They have a slightly sweet yet earthy flavor and a distinct, chewy texture.
Alternatively, you can use these mushrooms in pasta dishes, soups or stuffings to give your favorite recipes a kick of extra flavor and antioxidants.
Armillaria ostoyae Side Effects
Armillaria ostoya is unsafe to eat raw and can cause serious side effects. Some people may not be able to tolerate honey mushrooms even after cooking and may experience symptoms like nausea, cramps and stomach pain.
If you experience any side effects after consuming honey mushrooms, discontinue use immediately.
It’s also not advisable to consume alcohol with the mushrooms, and certain species should not be eaten within 12–24 hours of drinking alcohol to prevent negative symptoms.
Armillaria ostoyae Extract
Honey Mushroom (Armillaria ostoyae) produces a number of unique compounds, including several antibiotics and indole compounds, with high levels secreted into the culture medium during liquid fermentation.
In order to benefit from the full spectrum of this mushrooms' activity Mushroom capsules usually combines Armillaria ostoyae mycelial extract with A. mellea culture-medium extract. Standardized to 30% polysaccharides.
MycoNutri products are manufactured in the U.K. to EC food standards and are suitable for vegetarians and vegans (capsules are of plant origin). No additives are used and the products are dairy, gluten, maize, and soya-free.
Armillaria ostoyae Medicinal Properties
Armillaria ostoyae has many unique and intriguing biological properties, some of which may harbor great benefits to mankind. Bioluminescence, bioremediation, medicinal properties, and mycorrhizal associations comprise some of the more interesting attributes of Armillaria ostoyae.
Bioluminescence of A. ostoyae has apparently drawn the attention of man since ancient times when the man reportedly used chunks of bark laden with mycelial fans to mark paths during the night. It is not understood why different individuals and species of Armillaria exhibit variable levels of light emission. Armillaria spp. are also members of the so-called "white rot fungi", these fungi are known to decompose various environmental contaminants.
Like other "white rot fungi", Armillaria spp. can produce powerful enzymes that have the potential to decompose various toxic compounds; other "white rot fungi" have been shown to degrade harmful substances such as chlorophenols, polycyclic aromatic hydrocarbons (PAHs), and 2,4,6-trinitrotokuene (TNT). Also, an Armillaria sp. is a mycorrhizal symbiont of orchids in Asia.
Recently, supplements of Armillaria sp. have been found as an effective alternative to G. eleta because medicinal components of G. eleta consist primarily of metabolites that are produced by Armillaria sp.
Armillaria ostoyae Classification
This species was described in 1970 by Henri Charles Louis Romagnesi (1912 - 1999), who named it Armillariella ostoyae. Dark Honey Fungus was moved into its present genus and renamed Armillaria ostoyae in 1973 by Czech mycologist Josef Herink (1915 - 1999). Some authorities, particularly in the USA, now favor the name Armillaria solidipes Peck, based on a honey-coloured mushroom which they believe was the Dark Honey Fungus and had been described in a 1900 publication by American mycologist Charles Horton Peck (1833- 1917).
Synonyms of Armillaria ostoyae include Armillaria obscura (Schaeff.) Horak and Armillaria polymyces (Gray) Singer & Clémençon.
Armillaria ostoyae Cultivation
This parasitic mushrooms attack a living host plant, usually a tree, and eventually kill it.
Armillaria ostoyae also can be found growing on dead trees, but they probably started growing while the tree was alive and contributed to its demise.
It grows in a dense cluster at the base of trunks or stumps. Typically, the caps are honey-colored when young, darkening to yellowish brown as it ages. Sometimes, it has a few dark hairy scales towards the center of the cap. It has whitish to yellow stems.
Armillaria ostoyae Mycelium
One of the most distinguishing characteristics of the genus Armillaria is the formation of rhizomorphs. Rhizomorphs are cord-like structures composed of an aggregate of mycelium covered by a protective sheath. The sheaths act as a sort of armor for protection, which allows individuals of Armillaria to form expansive networks covering large areas.
The overall structure of rhizomorphs, as reviewed by Garraway et al. and Fox is highly complex. This complex structure allows for the translocation of oxygen, water, and other nutrients that aid in growth. While the sheath around the mycelium usually forms an impenetrable barrier, rhizomorphs at the soil surface can form pores that facilitate gas exchange; mechanisms also exist for water/nutrient absorption and exudate secretion.
Translocation of nutrients and metabolites can occur over substantial distances. Recently, it has been shown that rhizomorph growth forms can vary by species and that pathogenicity can be predicted by these growth forms. Rhizomorph production has also been linked to the ability of A. ostoyae to cause disease; genets that produce an abundance of rhizomorphs are thought to be more pathogenic.
Armillaria ostoyae Taste
They are called Honey Mushrooms not for their taste, but the color of their caps. The flesh is firm with a rich flavor. Some people think it tastes somewhat sweet, but they could be reading that in from the name. Other people taste a mildly-bitter aftertaste.
Recipe: Armillaria ostoyae Paprikas
3 c. packed honey mushroom caps, sliced
2 tablespoons oil
1 medium onion, diced
2 large cloves of garlic, minced
1 tablespoons paprika
1 teaspoon salt
1/4 teaspoon pepper
1-11.5 oz can V8
cooked egg noodles or dumplings
Blanch the sliced honey mushroom caps in a pot of water for a minute and drain.
Sautée the diced onion in the oil until soft, and add the minced garlic. Sautée for 2 minutes longer.
Add the paprika and the blanched mushrooms to the onions and garlic and cook over medium heat for 10 minutes.
Add the can of V8, and cook for 10 minutes longer, until the liquid has reduced by half. Add the salt and pepper to taste, and serve over hot noodles or dumplings. Robert also likes this on bread.
Recipe: Sauteed Armillaria ostoyae
Remember to always cook honey thoroughly, make darn sure they are done. If they are not cooked through they could give you an upset stomach.
Long clusters of honey mushrooms and their attached stems
Kosher salt and pepper
Fat for sauteing, like lard, grapeseed or canola
1 teaspoon unsalted butter
Trim the caps from the honey mushrooms and peel the stems.
Heat a pan with oil until lightly smoking and add the mushroom caps, cook the caps for 3 minutes on high heat until lightly colored, then add the stems and saute for another 3 minutes.
Continue cooking the mushrooms until they are well colored and thoroughly cooked.
When the mushrooms are golden and caramelized, add the butter, and season with salt and pepper to taste. Remove the mushrooms to paper towels to drain excess oil, serve immediately.
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