|
A. Beneficial Activities of Saprobic Fungi 5. Medicinal Uses of Fleshy Fungi
|
|
|
5. Medicinal Uses of Fleshy Fungi Quite
a number of mushrooms and bracket fungi are collected and grown for
medicinal purposes. Only a few of them will be covered here. a. The Varnish-skinned Fungus (Fig. 6-36):
Fig. 6-36. The common varnish-skinned fungus, Ganoderma lucidum. In Chinese folklore the basidiocarps of Ganoderma (Ling-chih) were a panacea for all types of diseases. They used it to treat hepatopathy, chronic hepatitis, nephritis, hypertension, hyperlipemia, arthritis, insomnia, anorexia, diabetes, asthma, ulcers, etc. (Lui et al. 1979. Chinese Med. J. 92:496-500). Because of its scarcity and resulting high price, only the rich could afford it. Today, Ganoderma is being produced on a large-scale basis for pharmacological and clinical studies (Fig. 6-37).
Fig. 6-37. Cultivation of Gandoderma for medicinal purposes. A number of species are used for fermentation purposes (Zhang, 1980. U.S. China Phar. Symp., Washington, DC. pp. 15-54). Jong & Birmingham (1992, Adv. Appl. Micro. 37: 101-134) provide a long list of compounds contained in species of Ganoderma. Species of Ganoderma are also cultivated and sold as “shelf ornaments” (Fig. 6-38).
Although Chinese medicines have long been used clinically, in most cases the chemical basis for their therapeutic action has not been understood. Antitumor action has been attributed to high-molecular weight polysaccharides. A ß-D-glucan from basidiocarps of G. applanatum, for example, showed significant tumor inhibition. An alcohol-ether soluble fraction of mycelium has been shown to protect the liver and enhance its detoxifying function. Intravenous injection of total alkaloids isolated from culture extracts increased coronary flow and lowered coronary resistance and myocardial oxygen consumption in dogs and cats. To evaluate the effect of Ganoderma on chlolesterol metabolism, Kabir et al. (1988. Nutr. Sci. Vitamin. 34:433-438) determined that the plasma total cholesterol level in rats fed Ganoderma was significantly lower than that of the controls. Alcohol and water extracts in human cell cultures exhibited both antiatherogenic and antiatherosclerotic action, indicating it may be useful in preventing and treating of arteriosclerosis. A glycoprotein derived from G. lucidum mycelia acts as an immunosuppressive agent in the treatment of allergic diseases and cell-mediated immune diseases. Japanese Patent 87:67,234.025 is for a fermentation product that is found to have significant therapeutic effect on patients with Alzheimer’s disease. And last but not least, hair-growing materials from Ganoderma mixed with Japanese horseradish effectively accelerates the growth of hair by providing a nutritive substance to the hair roots (Anan Koryo Sangyo, 1984, Japanese Pat. 87:270,595). Ganoderma seems to contain many compounds, especially polysaccharides and triterpenoids (Willard, T. 1990. Reishi Mushroom: Herb of Spiritual Potency and Medical Wonder. Sylvan. Issaquah). In oriental history and folklore, ling chih is a supremely good omen, a symbol of happiness, good fortune, good health, longevity, even life with the immortals. Species of Reishi or Ling chih have a long and fascinating history. Ssu-ma Ch’ien, a Ch’in Dynasty historian (ca. 215 BC), tells of an obsessive ongoing search for a wondrous “chih” or fungus directed by the King, Shi-Huang. A mariner named Hsu Fu was dispatched out to sea to search remote islands for chih. He came back with fantastic tales of palaces made of chih. The palaces were so bright that they lit up the heavens and the fungus was said to have the ability to revive the dead (Shih chou chi, Notes on Ten Continents). In 109 BC, a fungus believed to be Ganoderma appeared on site at the construction of the new Kan-chuan Imperial Palace. It was called “ling chih”, the same name that was printed on silk cloth with a Ganoderma specimen going back to the Han Dynasty (100 BC to 100 AD). CLICK HERE TO GO TO TOP OF RIGHT SIDE COLUMN
|
b. Shiitake (Lentinus edodes) (Fig. 6-39):
Fig. 6-39. Lentinus edodes, the widely cultivated shiitake mushroom. According to ancient Chinese tradition, consumption of shiitake was recommended for long life and good health. According to Mori (1974, Mushrooms as health foods, Tokyo), Wu Juei, a Chinese physician of the Ming dynasty (1368-1644) claimed that it preserved health, improved stamina and circulation, cured colds, and in modern times lowered blood cholesterol. Jong and Birmingham (1993. Adv. Appl. Micro. 38: 18-35) listed 8 different areas in which medicinal benefit of the shiitake mushroom had been determined. These included: Anti-Hypertension and Anti-Cholesteremic. A germanium-rich beverage of L. edodes (shiitake) is both anti-hypertensive and anti-cholesteremic. Manufacture of cholesterol-lowering and immunoactivating eritadene has been produced by Nippon-Food since 1987. The chief compound, lentinan, is a B-glucan found predominantly in the cuticle of L. edodes. Soluble protein extracted from shiitake basidiocarps proved to be a useful viricide. A mixture of polysaccharides and cytokinin substances, mainly zeatin and zeatin riboside, proved effective against viral hepatitis. A viricide composition to prevent multiplication of HIV virus, herpes virus, and hepatitis B-virus was obtained by fermentation of vegetable biomass with L. edodes (Noda-Food, 1990). Lentinan has been shown to exert prominent anti-tumor effects in marine allogeneic, syngeneic and autochthonous hosts, to prevent chemical and viral carcinogenesis, to increase host resistance to bacterial, viral, and parasitic infections, and is effective against HIV and aids infections. In 1987 it was the eight top-selling anti-cancer drug in Japan (Fukushima, 1989. Nature 342:850-851). c. Maitake (Grifola):
Fig. 6-40. The Maitake mushroom Grifolia frondosa. (provided by Tim Baroni) The bracket fungus (Polyporaceae) Grifola (Fig. 6-40), known in Japan as maitake, is a member of an economically important group that causes serious diseases of trees and the decay of timber such as soft rots, white rots, and brown rots. Three common species, G. frondosa, G. umbellata, and G. gigantea, are edible when young. They are grown indoors in sterilized plastic bags of compost, much like indoor grown shiitakes. The underground portions of these bracket fungi have been found to be of medicinal value. Jong and Birmingham (1990. World J. Microbiol Biotech. 6:227-235) summarized the various medicinal qualities of this mushroom. These include: antibiotic activities in which a compound, grifolin, was found to be bactericidal. Antitumor substances called D-fractions have been obtained from extracts of the basidiocarp, the liquid culture, and the extracellular polysaccharides of Grifola. This substance also reduces the side effects of chemotherapy. Researchers at the National Cancer Institute have indicated that maitake may be an effective defense against HIV. A serious skin cancer that is one manifestation of AIDS may be treated with maitake extracts (Turner, L., Lets Live, April 1997). d. Turkey-Tail: Trametes versicolor
Fig. 6-41. The common turkey-tail bracket fungus, Trametes versicolor. This fungus is a common bracket fungus that causes wood decay on a wide variety of both broadleaf and conifer hosts. A protein-bound polysaccharide preparation of Trametes versicolor (Fig. 6-41) is a non-specific immunostimulator produced in Japan for clinical treatment of stomach, esophagus, colon, rectum, lung, and mammary gland cancers. By 1984 it ranked 19th on the list of the world’s most commercially successful drugs with annual sales of 255 million dollars (Yang et al. 1992. J. Immun. Immunophar. 12: 29-34). |
