Mushrooms are known for their nutritional and medicinal value as well as for the diversity of bioactive compounds they contain. Coriolus versicolor, aka “turkey-tail mushroom”, is a mushroom commonly found throughout North America, Asia, and Europe. The visible form of Coriolus versicolor is a fan-shaped mushroom with wavy margin and colored concentric zones. The colors of the distinctive layers created by these bodies may be light to dark brown or gray and resemble a turkey tail. Coriolus versicolor is an obligate aerobe that is commonly found year-round on dead logs, stumps, tree trunks, and branches. The fungus occurs throughout the wooded temperate zones of Asia, Europe, and North America and may be the most common shelf fungus in the Northern Hemisphere. The mushroom belongs to the family Basidiomycotina. This mushroom has long been treasured in China where it is called Yun Zhi, or “cloud fungus”, and in Japan where it is known as Kawaratake, or “mushroom by the river bank”.
Coriolus versicolor was recorded in the Compendium of Chinese Materia Medica by Li Shi Zhen during the Ming Dynasty in China, as being beneficial to health and able to bring longevity if consumed regularly. More than 120 strains of Coriolus versicolor were recorded in the Compendium of Chinese Materia Medica. According to the theory of traditional Chinese medicine (TCM), Coriolus versicolor has a slightly sweet taste and cold property, exerting its effects in the body via the liver and spleen. As a medicinal substance documented in some TCM classics, Coriolus versicolor is considered useful for dispelling heat, removing toxins, strengthening physique, increasing energy and spirit, and enhancing the host’s immune function. In the clinical practice of TCM, Coriolus versicolor is often indicated for various types of cancers, chronic hepatitis, and infections of the upper respiratory, urinary, and digestive tracts. In Asia, Coriolus versicolor is used as a preventive tonic and therapeutic agent for numerous conditions. And throughout the world, it has also become a popular mushroom for treating a variety of cancers. Overall, both the mycelium and fruiting body of the mushroom exhibit immune-enhancing properties and are shown to have potent anticarcinogenic activity.
Coriolus versicolor is primarily a biological response modifier. DNA-microarray analysis indicates that the mushroom extract inhibits the expression of cell cycle regulatory genes and suppressed metastatic behavior by inhibiting cell adhesion, cell migration, and cell invasion. The inhibition of metastatic behavior is linked to the suppression of urokinase plasminogen activator.1 A variety of other anticarcinogenic mechanisms have been observed in laboratory studies of Coriolus versicolor extract. Its extract can alter the expression of the p53 gene2 and suppress heat shock proteins3 that are overexpressed in a wide range of human cancers and are implicated in tumor cell proliferation.
The protein-bound polysaccharides or polysaccharopeptides produced by Coriolus versicolor are effective immunopotentiators, which are used to supplement chemotherapy and radiotherapy as well as the treatment of various infectious diseases. Actually, an extremely broad range of physiological effects has been associated with the use of Coriolus versicolor polysaccharopeptides. Some of the main effects include:
immunopotentiation by inducing production of interleukin-6, interferons, immunoglobulin-G, macrophages, and T-lymphocytes;
countering of immunosuppressive effects of chemotherapy, radiotherapy, and blood transfusions;
antagonization of immunosuppression induced by tumors;
inhibition of proliferation of various cancers by inducing production of superoxide dismutase (SOD), glutathione peroxidase, and general immune enhancement;
improvement of appetite and liver function; calming of the central nervous system;
enhancement of pain threshold;
and improvement of intestinal disorders.
Researchers discovered and labeled two of this mushroom’s active anticancer polysaccharides as PSK, or Polysaccharide-K, and PSP, or Polysaccharide-P. They are chemically similar, but PSK contains fucose, while PSP contains rhamnose and arabinose. Both PSK and PSP extracts exhibit immunomodulating and antitumor activity.4 PSK, also known and marketed as “Krestin”, has been studied most extensively and is in wide clinical use as an adjunctive and adjuvant cancer therapy in Japan and China. PSK has been shown to improve survival rates in patients with gastric5, 6 and colorectal7, 8, 9 cancers. Other research on PSK has been shown to have antioxidant capacity which may allow it to play a role as a normal tissue chemo- and radio-protector when used in combination with adjuvant or definitive chemotherapy and/or radiotherapy in the treatment of cancer, while it may also enable it to defend the host from oxidative stress.10, 11
In the in vitro situation, these polysaccharide extracts were found effective for activating T lymphocytes,12, 13, 14, 15, 16, 17, 18 B lymphocytes,19 monocytes/ macrophages,20, 21, 22 bone marrow cells,23 natural killer cells, and lymphocyte-activated killer cells as well as promoting the proliferation and/or production of antibodies and various cytokines such as interleukin (IL)-2 and IL-6, interferons, and tumor necrotic factor.24, 25 Based on the clinical data accrued to date, Coriolus versicolor extracts appear highly effective for restoring depressed blood levels of lymphocytes and IL-2 and weakened antitumor activity of natural killer cells.26, 27, 28, 29, 30, 31
Most Coriolus versicolor clinical research has focused on its effects on overall survival rates. In 1984, Sugimachi’s group at Kyushu University published a retrospective analysis of breast cancer patients with recurrent disease who were treated with Coriolus versicolor extract as Krestin (PSK).32 Some patients received chemotherapy only, while others received both chemotherapy with Krestin (PSK) immunotherapy. They demonstrated that the survival rate after recurrence was significantly extended by Krestin (PSK) immunotherapy compared to chemotherapy alone. A 1997 study of breast cancer patients with vascular invasion also showed that PSK given with cytotoxic chemotherapy significantly increased survival rates.33 In 1992, a Japanese randomized trial of 914 women evaluated tamoxifen and Krestin (PSK) as an addition to the then-conventional chemotherapy. Analysis revealed that Krestin (PSK) significantly extended survival in ER-negative, stage IIA patients without lymph node involvement.34 A systemic review and meta-analysis conducted in 2012 analyzed the efficacy of Coriolus versicolor on survival in cancer patients from 13 clinical trials using computerized database and manual search. The researchers concluded, “strong evidence is provided that Yun Zhi (Coriolus versicolor) has survival benefit in cancer patients, particularly in breast, gastric, and colorectal carcinoma”.35
After a quarter-century of trials indicating Coriolus versicolor extract can improve cancer survival, the cumulative human findings amount to a recommendation for its inclusion in standard anticancer protocols. PSK as Krestin was approved in 1977 as a cancer therapy by the Japanese National Health Registry and by 2004 represented 25% of the total national costs of cancer care in Japan.36 According to Chinese studies, Coriolus versicolor extract is nontoxic, both in the short and long term.37, 38 With its risks for adverse effects virtually nonexistent, this mushroom’s contribution in cancer treatment can only be positive.
In some in vivo animal studies, Coriolus versicolor extract was observed to display a broad spectrum of antibacterial and antifungal activities against common pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, Klebsiella pneumoniae, Listeria monocytogenes, and Streptococcus pneumoniae. Intraperitoneal administration was more effective than oral administration, which required repeated administration for 2 weeks before significant therapeutic effect could be achieved.39 The observed antimicrobial effects of the extract are possibly due to the activation of polymorphonuclear cells and an increased secretion of antimicrobial cytokines (e.g., tumor necrosis factor, IL-1). Coriolus versicolor extracts have also been reported to show in vitro antiviral activities.40, 41
In summary, Coriolus versicolor has been shown to manifest immunomodulatory and antitumor activity in both experimental animals and cancer patients. Its ability to diminish side effects of radiotherapy and chemotherapy make its inclusion as an adjunct for cancer treatment worthy of consideration. It has a potent antimicrobial effect and may be used to treat both acute and chronic viral infections or to prevent infections.
Dosage and Availability
Dosage, as with any product, varies from individual to individual depending on one's condition, tolerance, and what is being treated. Hence, use and dosage should be directed by a qualified heath professional. Coriolus versicolor extracts are widely available as oral proprietary products on the market. The growing popularity of aqueous Coriolus versicolor extracts as an adjunct medical modality to conventional cancer therapies has generated substantial commercial interest in developing these extracts into consistent and efficacious oral proprietary products. These products are normally considered as health supplements and can be purchased without a prescription even though they are extensively used in cancer treatment for the relief of side effects associated with radiation therapy and chemotherapy. However, in China and Japan, certain Coriolus versicolor products are classified as drugs for specific therapeutic indications. While the extract version of Coriolus versicolor used in China and Japan, known as Krestin (PSK), is not available in the U.S., organic extracts and pure freeze-dried mycelial powder is available from several reputable companies. A dosage of 9 to 15g Coriolus versicolor decocted with water is recommended for oral daily dosing. For dried Coriolus versicolor extracts, 3 to 6 g is the daily oral dosage used in most clinical trials. For prevention of cancer recurrence, some physicians recommend 500 mg to 1000 mg (one gram) daily.42
Coriolus versicolor is generally considered safe for human consumption, irrespective of age and gender. However, the use of Coriolus versicolor may be contraindicated in patients suffering from autoimmune diseases or receiving bone marrow transplants. The LD50 of crude Coriolus versicolor extract administered orally in mice was greater than 18 g/kg. No death, toxic symptoms, or obvious hematological and pathohistological changes were observed after a 3-month dosing period. No mutagenic and cytotoxic effects were detected with high doses of CV extract.43, 44, 4
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1. Wan JMF, Sit WH, Yang X, Jiang P, Wong LY. Polysaccharopeptides derived from Coriolus versicolor potentiate the S-phase specific cytotoxicity of Camptothecin (CPT) on human leukemia HL-60 cells. Chinese Medicine. 2010;5:16.
2. Yoshikawa R, Yanagi H, Hashimoto-Tamaoki T, Morinaga T, Nakano Y, Noda M, et al. Gene expression in response to anti-tumour intervention by polysaccharide-K (PSK) in colorectal carcinoma cells. Oncol Rep 2004 Dec;12(6):1287-93.
3. Fisher M, Yang L-X. Anticancer effects and mechanisms of polysaccharide-K (PSK): implications of cancer immunotherapy. Anticancer Research 2002;22:1737-54.
4. Ikuzawa M, Matsunaga K, Nishiyama S, et al. Fate and distribution of an antitumor protein bound polysaccharide PSK (Krestin). Intl J Immunopharmacol 1988;10:415-423.
5. Nakazato H, et al. Efficacy of immunochemotherapy as adjuvant treatment after curative resection of gastric cancer. Study Group of Immunochemotherapy with PSK for Gastric Cancer. Lancet 1994; 343(8906): 1122-6.
6. Niimoto M, et al. Postoperative adjuvant immunochemotherapy with mitomycin C, futraful and PSK for gastric cancer. An analysis of data on 579 patients followed for five years. Jpn J Surg 1988; 18(6): 681-6.
7. Ohwada S, et al. Adjuvant immunochemotherapy with oral Tegafur/Uracil plus PSK in patients with stage II or III colorectal cancer: a randomised controlled study. Br J Cancer 2004; 90(5): 1003-10.
8. Mitomi T, et al. Randomized, controlled study on adjuvant immunochemotherapy with PSK in curatively resected colorectal cancer. The Cooperative Study Group of Surgical Adjuvant Immunochemotherapy for Cancer of Colon and Rectum (Kanagawa). Dis Colon Rectum 1992; 35(2): 123-30.
9. Torisu M, et al. Significant prolongation of disease-free period gained by oral polysaccharide K (PSK) administration after curative surgical operation of colorectal cancer. Cancer Immunol Immunother 1990; 31(5): 261-8.
10. Fisher M, Yang LX. Anticancer effects and mechanisms of polysaccharide-K (PSK): implications of cancer immunotherapy. Anticancer Res. 2002;22:1737–1754.
11. Yang QY. Yun Zhi polysaccharopeptide (PSP) and the general aspects of its research. Fung Sci. 1997;12:1–8.
12. Li XY: Advances in immunological studies in PSP, in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999;39-46.
13. Liu F, Ooi VEC, Fung MC: Analysis of immunomodulating cytokines mRNAs in the mouse induced by mushroom polysaccharides. Life Sci 1999;64(12):1005-1011.
14. Sakagami H, Aoki T, Simpson A, Tanuma SI: Induction of immunopotentiation activity by a protein-bound polysaccharide, PSK [review]. Anticancer Res 1991;11:993-1000.
15. Tsukagoshi S, Hashimoto Y, Fugii G, Kobayashi H, Nomoto K, Orita K: Krestin (PSK). Cancer Treat Rev 1984;11:131-155.
16. Ueno S, Yoshikumi C, Omura Y, Fugii T, Wada T, Takahashi E, Hirose F: US patent 4,699,787: nitrogen-containing polysaccharide, October 13, 1987.
17. Ueno S, Yoshikumi C, Omura Y, Fugii T, Wada T, Takahashi E, Hirose F: US patent 4,851,395: nitrogen-containing polysaccharide, July 25, 1989.
18. Wang HX, Ng TB, Liu WK, Ooi VEC, Chang ST: Polysaccharidepeptide complexes from the cultured mycelia of the mushroom Coriolus versicolor and their culture medium activate mouse lymphocytes and macrophages. Int J Biochem Cell Biol 1996;28(5): 601-607.
19. Li XY: Advances in immunological studies in PSP, in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999; 39-46.
20. Sakagami H, Aoki T, Simpson A, Tanuma SI: Induction of immunopotentiation activity by a protein-bound polysaccharide, PSK [review]. Anticancer Res 1991;11:993-1000.
21. Tsukagoshi S, Hashimoto Y, Fugii G, Kobayashi H, Nomoto K, Orita K: Krestin (PSK). Cancer Treat Rev 1984;11:131-155.
22. Wang HX, Ng TB, Liu WK, Ooi VEC, Chang ST: Polysaccharidepeptide complexes from the cultured mycelia of the mushroom Coriolus versicolor and their culture medium activate mouse lymphocytes and macrophages. Int J Biochem Cell Biol 1996;28(5): 601-607.
23. Sakagami H, Aoki T, Simpson A, Tanuma SI: Induction of immunopotentiation activity by a protein-bound polysaccharide, PSK [review]. Anticancer Res 1991; 11: 993-1000.
24. Sakagami H, Aoki T, Simpson A, Tanuma SI: Induction of immunopotentiation activity by a protein-bound polysaccharide, PSK [review]. Anticancer Res 1991;11:993-1000.
25. Tsukagoshi S, Hashimoto Y, Fugii G, Kobayashi H, Nomoto K, Orita K: Krestin (PSK). Cancer Treat Rev 1984;11:131-155.
26. Xie SQ: The effect of PSP on red cell immunity: a clinical study on gastric cancer patients, in: Yang QY, Kwok CY (eds.), Proceedings of PSP International Symposium. Shanghai, China: Fudan University Press, 1993;241-242.
27. Liao ML, Zhao JM: The II stage clinical tests of PSP in the treatment of lung cancer, in: Yang QY, Kwok CY (eds.), Proceedings of PSP International Symposium. Shanghai, China: Fudan University Press, 1993;243-256.
28. Wu CP, Wu J, Sun WH: The curative effect of Yun Zhi polysaccharopeptide (PSP) on stomach cancer, in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999; 322-326.
29. Yao WQ: Prospective randomized trial for radiotherapy plus PSP in the treatment of esophageal carcinoma, in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999;310-313.
30. Liu TF: PSP in clinical cancer therapy, in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999;68-75.
31. Shi JH, Chen T, Lian ZR: The clinical research of the effect of PSP on the immunological function of stomach cancer patients during operation and chemotherapy, in: Yang QY, Kwok CY (eds.), Proceedings of PSP International Symposium. Shanghai, China: Fudan University Press, 1993;232-240.
32. Sugimachi K, Inokuchi K, Matsuura H. et al. Hormone conditioned cancer chemotherapy for recurrent breast cancer prolongs survival. Jpn J Surg. 1984;14:217–221.
33. Yokoe T, Iino Y, Takei H, Horiguchi J, Koibuchi Y, Maemura M, et al. HLA antigen as predictive index for the outcome of breast cancer patients with adjuvant immunochemotherapy with PSK. Anticancer Research. 1997 Jul-Aug;17(4A):2815-8.
In this study patients were divided into two groups:
1. PSK plus 5-fluorouracil, cyclophosphamide, mitomycin, predonisolone (FEMP)
2. Cytotoxic chemotherapy only (FEMP)
Patients received two 28-day courses of this treatment a year for five years. This study stratified each of these groups by serotype HLA type B40 positive or negative. The survival results of the PSK group were significant. The disease-free survival rates at five and 10 years for the FEMP plus PSK group with B40 positive was 100%. For those with B40 negative, the five- and ten-year survival was 76% for the FEMP plus PSK and only 55% for the FEMP group.
34. Toi M, Hattori T, Akagi M, et al. Randomized adjuvant trial to evaluate the addition of tamoxifen and Krestin (PSK)™ to chemotherapy in patients with primary breast cancer. 5-Year results from the Nishi-Nippon Group of the Adjuvant Chemoendocrine Therapy for Breast Cancer Organization. Cancer. 1992;70:2475–2483.
35. Eliza WL, Fai CK, Chung LP. Efficacy of Yun Zhi (Coriolus versicolor) on survival in cancer patients: systematic review and meta-analysis. Recent Pat Inflamm Allergy Drug Discov. 2012 Jan;6(1):78-87.
36. Hobbs C. Medicinal value of turkey tail fungus Trametes versicolor (L.:Fr.) Pilat (aphyllophoromycetideae) Int J Med Mushrooms. 2004;6:195–218.
37. Jian X, Huang L, Zhou Y, et al. Subchronic toxicity test of polysaccharopeptide of Yun Zhi (PSP). In: Yang QY (ed), International Symposium on Traditional Chinese Medicine and Cancer: Development and Clinical Validation—Advances Research in PSP. Hong Kong Association for Health Care Ltd; 1999:272–284.
38. Jin TY. Toxicological research on Yun Zhi polysaccharopeptide (PSP). In: Yan QY (ed), International Symposium on Traditional Chinese Medicine and Cancer: Development and Clinical Validation—Advances Research in PSP. Hong Kong Association for Health Care Ltd; 1999:76–79.
39. Sakagami H, Takeda M: Diverse biological activity of PSK (Krestin), a protein-bound polysaccharide from Coriolus versicolor (Fr.) Quel., in: Chang ST, Buswell JA, Chiu SW (eds.), Mushroom Biology and Mushroom Products. Hong Kong: Chinese University Press, 1993;237-245.
40. Zhu P, Yang MP, Chen ZN: Studyon the inhibitory effect of purified PSP (PCV) on the respiratory syncytial virus, in: Yang QY, Kwok CY (eds.), Proceedings of PSP International Symposium. Shanghai, China: Fudan UniversityPress, 1993;153-154.
41. Collins RA, Ng TB: Polysaccharopeptide from Coriolus versicolor has potential for use against human immunodeficiency virus type 1 infection, in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999;181-186.
42. Several excellent mushroom extracts are available from Fungi Perfecti, Inc., Olympia, WA. (www.fungi.com). Fungi Perfecti sells Coriolus versicolor as “Host Defense® Turkey Tail”. Host Defense® Turkey Tail uses activated, freeze-dried, certified organic mushroom mycelium, with a full spectrum of constituents: polysaccharides (beta glucans, arabinoxylane, glucose, xylose, galactose and mannose), glycoproteins, ergosterols, triterpenoids and other myco-nutrients. Two capsules of Host Defense® Turkey Tail are approximately 1000 mg. To obtain a dosage of 6 grams daily of this product it is necessary to consume 4 capsules three times per day. Capsules may be opened and dissolved into warm water.
43. Jin TY: Toxicological research on Yun Zhi polysaccharopeptide (PSP), in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999;76-79.
44. Jiang XZ, Huang LM, Zhou YF, Wang MM: Subchronic toxicity test of polysaccharopeptide of Yun Zhi (PSP), in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999;272-284.
45. Zhong BZ, Zhou YG, Zhou LF, Qian ZB: Genetic toxicity test of Yun Zhi polysaccharopeptide (PSP), in: Yang QY (ed.), Advanced Research in PSP. Hong Kong: Hong Kong Association for Health Care, 1999; 285-294.