Asian countries have been the leaders in research on the medicinal value of several edible mushrooms. While animal research has been the dominant method of study in the past, researchers are now more involved in clinical trials using human subjects. Most of the research has been cancer related, but results have also shown a reduction of blood pressure and cholesterol, enhancement of the immune system, antiviral and anti-inflammatory properties, treatment of anaphylactic shock, anti-HIV properties, and an increase of oxygen utilization and antioxidant properties as a result of using mushroom extracts during therapy (Chen and Miles, 1996). Ganoderma lucidum (reishi), Lentinula edodes (shiitake), Hericium erinaceum (lions mane), Pleurotus ostreatus (oyster mushroom), and Grifola frondosa (maitake) are just a few of the cultivated mushroom species that have been analyzed for medicinal value. There are, however, over 270 known mushrooms with medicinal benefits. In the United States, the phytopharmaceutical value of these mushrooms has only recently been recognized and clinical trials have been established to determine the medicinal characteristics of these mushrooms (Kimmons, 2003; Underwood, 2003). The principal medicinal component of most of these mushrooms is high-molecular-weight polysaccharides.
Over the next year each edition of this newsletter will document clinical trials or research recommendations for the use and effectiveness of various mushrooms. While the recommendations given by researchers are assumed to be accurate, you should always check with a physician before using any food supplements. Today's mushroom is Grifola frondosa or more commonly referred to as the maitake mushroom.
Maitake is a fungus that grows most frequently on fallen trees or stumps of beech and oak. Maitake, also known as "hen of the woods" and "dancing mushrooms," forms large fan-shaped mushroom heads that often fuse together in masses at the base or on the roots of broadleaf trees. In traditional Chinese medicine, it has been used for improving spleen and stomach ailments, calming nerves, and treating hemorrhoids (Hobbs, 1995; Jong and Birmingham, 1990). Recent studies have shown that polysaccharides and polysaccharide-protein complexes from this mushroom have significant anti-cancer activity (Hishida et al., 1988; Kurashige et al., 1997; Ohno et al., 1985). Other fractions (D-, GF-1, grifolan-7N) from maitake exhibit immunological enhancement together with properties of anti-HIV, antihypertension, antidiabetic, and antiobesity (Adachi et al., 1988; Borchers et al., 1999; Iino et al., 1985; Jones, 1998; Kabir et al., 1987; Kubo et al, 1994; Kubo and Nanba, 1966; Mizuno and Zhuang, 1995; Nakai et al., 1999; Nanba, 1993). The ß-glucan fractions from this mushroom are now being used by over 3,000 health professionals in the United States for the prevention and treatment of flu and common infection, AIDS (HIV), diabetes mellitus, hypertension, hypercholesterolemia, and urinary tract infections (Choi et al., 2001; Cichoke, 1994; Kabir et al., 1989; Kubo et al.,1997; Kubo et al., 1994; Smith, 2002; Talpur, 2002).
Much research has been conducted on antioxidants to help the human body reduce oxidative damage. Mau (2002) determined that Grifola frondosa and Hericium erinaceus have aided oxidant reduction by 39.6 percent and 69.4 percent, respectively. Several studies have been conducted to measure maitake's effect on obesity. In animal studies, lack of weight gain or weight loss was significant (Ohtsuru, 1992). In an obesity study on humans by Dr. Yokota (1992), 30 patients were given a powdered maitake food supplement for two months with no change in their regular diets. All patients successfully lost 7-13 pounds.
Maitake, as is true of many other mushrooms, is predominately an immune booster. The human body uses these high-molecular-weight polysaccharides to enhance its immune system. Most mushrooms high-molecular-weight polysaccharides are not cell-killers. In fact, much of the research suggests that maitake and other mushrooms, taken along with traditional therapy, provides improved response and recovery as well as protecting healthy cells from cancer.
Maitake is available as an extract or a dried encapsulated product and can be purchased on the Internet or at health food and nutrition outlets. When purchasing maitake extracts and supplements read the label and compare ingredients. Some products guarantee a standardized percentage of polysaccharide while others are supplemented with oats and other ingredients.
Borchers, A. J. Stern, R. Hackman, C. Keen, M. Gershwin. (1999). Mushrooms, tumors and immunity. Proceedings of The Society for Experimental Biology and Medicine, 221 (4), 281-93.
Chen, A., P. Miles. (1996). Biomedial research and the application of mushroom nutriceuticals from Ganoderma lucidum mushroom biology and mushroom production: Proceedings of the 2nd international conference, June 9-12, 1996, University Park, Pennsylvania. Pennsylvania State University: World Society for Mushroom Biology and Mushroom Products, 161-175.
Choi, H. S., H. Y. Cho, H. C. Yang, K. S. Ra and H. J. Suh. (2001). Angiotensin i-converting enzyme inhibitor from Grifola frondosa. Food Research International 3, 177-182.
Cichoke, A. (1994). Maitake: The king of mushrooms. Townsend Letter for Doctors, 432-434.
Hishada, I, H. Nanba and H. Kuroda. (1988). Antimour activity exhibited by orally administered extracts from fruit-body of Grifola frondoa (maitake). Chemical and Pharmaceutical Bulletin 35(5), 1819-1827.
Hobbs C. (1995). Medicinal mushrooms: An exploration of tradition, healing and culture. Santa Cruz, CA: Botanica Press, 125-8.
Iino, K., N. Ohno, I. Suzuki, T. Miyazaki and T. Yadomae. (1985). Structural characterization of a neutral antitumour ß-D-glucan extracted with hot sodium hydroxide from cultured fruit bodies of Grifola frondosa. Carbohydrate Research, 141,111-119.
Jones, K. (1998). Maitake: A potent medicinal food. Alternative & Complementary Therapies 4, 420-429.
Jong, S. C. and J. M. Birmingham. (1990). The medicinal value of the mushroom Grifola. World Journal of Microbiology and Biotechnology 6, 227-235.
Kabir, Y., M. Yamaguchi and S. Kimura. (1987). Effect of shiitake and maitake mushrooms on blood pressure and plasma lipids of spontaneously hypertensive rats. Journal of Nutritional Science & Vitaminology, 33 (5), 341-346.
Kabir, Y. and S. Kimura. (1989). Dietary mushrooms reduce blood pressure in spontaneously hypertensive rats. Journal of Nutritional Science & Vitaminology 35 (1), 91-94.
Kimmons, T. (2003). Effects of management on the yield and high-molecular-weight polysaccharide content of shiitake (Lentinula edodes) mushrooms. Personal Communication.
Kubo, K., and H. Nanba. (1997). Anti-byperliposis effect of Maitake fruit body (Grifiola frondosa). Biological and Pharmaceutical Bulletin, 17(8), 1106-1110.
Kubo, K., H. Aoki and H. Nanba. (1994). Anti-diabetic activity present in the fruit body of Grifola fondosa (maitake). Biology Pharmaceutical Bulletin, 17 (8), 1106-10.
Kubo, K., and Nanba, H. (1966). The effect of Maitake mushrooms on liver and serum lipids. Alternative Therapeutic Health Medicine, 2, 62-66.
Kurashiga, S., Y. Akuzawa, and F. Eudo. (1997). Effects of Lentinus edodes, Grifiola frondosa and Pleurotus ostreatus administration on cancer outbreaks and activities of macrophages and lymphocytes in mice treated with a carcinogen N-butyl-N1-butamolinitreso-amine. Immunopharmacology and Immunotoxicology 19:175-183.
Mau, J., H. Lin and S. Song. (2002). Antioxidant properties of several specialty mushrooms. Food Research International 3, 519-526.
Ohno, N., K. Iino, I. Suzuki, S. Oikawa, K. Sato, T. Miyazaki and T. Yadomae. (1985). Neutral and acidic antitumor polysaccharides extracted from cultured fruit bodies of Grifola frondosa. Chemical and Pharmaceutical Bulletin, 33 (3), 1181-1186.
Ohtsuru, M. (July 1992). Anti-obesity activity exhibited by orally administered powder of maitake mushroom (Grifola frondosa). Anshin,198.
Smith, J., N. Rowan and R. Sullivan. (2002). Medicinal Mushrooms: Their therapeutic properties and current medical usage with special emphasis on cancer treatments. University of Strathclyde, Glasgow, UK, 256.
Talpur, N, B. Echard, A. Fan, O. Jaffari, D. Bagchi and H. Preuss. (2002). Antihypertensive and metabolic effects of whole maitake mushroom powder and its fractions in two rat strains. Molecular and Cellular Biochemistry 237, 129-136.
Underwood, A. (2003). The magic of mushrooms. Newsweek 142 (18), 61.
Yokota, M. (July 1992). Observatory trial at anti-obesity activity of maitake mushroom (Grifola frondosa). Anshin, 202.