Maitake

Maitake (Grifola frondosa referring to a mythical griffin), also known as Sheep’s Head, Ram’s Head and Hen of the Woods (IPA ), is an edible polypore mushroom. It grows in clusters at the foot of trees, especially oak. The Japanese named it "maitake", literally meaning "dancing mushroom." Hen of the woods should not be confused with the similarly named edible bracket fungi, chicken of the woods (Laetiporus sulphureus), also known as "sulphur shelf".

Maitake is indigenous to the northeastern part of Japan and North America, and is prized in traditional Chinese and Japanese herbology as an adaptogen, an aid to balance out altered body systems to a normal level. Most people find its taste and texture enormously appealing, though the mushroom has been alleged to cause allergic reactions in rare cases.

Morphology
Like the sulphur shelf mushroom, hen of the woods is a perennial fungus that often grows in the same place for a number of years in succession. It occurs most prolifically in the northeastern regions of the United States, but has been found as far west as Idaho.

Hen of the woods grows from an underground tuber-like structure, about the size of a potato. The fruiting body, occurring as large as 60 cm, is a cluster consisting of multiple grayish-brown caps which are often curled or spoon-shaped, with wavy margins and 2-7 cm broad. The undersurface of each cap bears approximately one to three pores per millimeter, with the tubes rarely deeper than 3 mm. The milky-white stipe (stalk) has a branchy structure and becomes tough as the mushroom matures.

Maitake, an edible mushroom of the (Polyporaceae) family, can grow up to over 50 pounds (20 kilograms), earning this giant mushroom the title "King of Mushrooms."

Use in traditional Oriental medicine
The underground tubers from which hen of the woods arises has been used in traditional Chinese and Japanese medicine to enhance the immune system. Researchers have also indicated that whole maitake has the ability to regulate blood pressure, glucose, insulin, and both serum and liver lipids, such as cholesterol, triglycerides, and phospholipids, and may also be useful for weight loss.

Maitake is rich in minerals (such as potassium, calcium, and magnesium), various vitamins (B2, D2 and Niacin), fibers and amino acids. The active constituent in maitake for enhancing the immune actively has been identified in the late 1980s to be the protein-bound polysaccharide compound, beta-glucan, an ingredient found especially in the family of polyporaceae.

Maitake D-fraction
Most research on maitake has focused on the use of maitake D-fraction for treating various malignancies. D-fraction consists of a highly standardized and purified active beta-glucan (both -3-branched beta-1,6 glucan AND 6-branched beta-3 1.3 glucan), and approximately 30% of protein, extracted from maitake mushroom's fruiting body. The bioactive D-fraction, extracted from maitake, is prepared by a standardised procedure developed by "Maitake Products, Inc.", East Rutherford, New Jersey.

Active beta-glucans in D-fractions have unique polysaccharide structures, and the degree of branching is greater than any beta-glucan found in any other medicinal mushrooms that demonstrate similar immune stimulatory properties. Researchers theorize that the complexity of branching makes D-fraction most potent for enhancing the immune system via oral administration, leading to a higher tumor reduction in several animal studies.

Most other mushroom extracts fail to show oral activity in pre-clinical studies. The Memorial Sloan-Kettering Cancer Center in New York is conducting a study in collaboration with the New York Presbyterian Hospital-Weill Medical College of Cornell University to determine if D-fraction can stimulate the immune system, without causing any side effects or toxicity. Further laboratory studies and extensive clinical studies are under way in collaboration with leading research institutes, both in the United States and in Japan.


 * Reference: Pahang Pharmacy. Maitake boost to the immune system, New Sunday Times, Malaysia, dated September 18, 2005.