Chaga (Inonotus obliquus)
Other Names
Kabanoanatake (Japanese), bai hua rong (Chinese), clinker polypore, clinker fungus, cinder conk, black birch toughwood, birch mushroom.
Natural Habitat
North America, Eastern Europe, Russia, Poland, Western Siberia. Chaga grows in boreal forests, especially on birch. Grows on living and dead trees and stumps1.
Key Components
Betulinic acid; polysaccharides; triterpenoids; melanin.
Overview
Chaga is a polypore, or “conk” mushroom, which grows widely in the boreal forests of Eastern Europe and North America. Chaga is commonly found on birch, although it grows on other types of trees as well. In addition to demonstrating superior antioxidant and genoprotective activity2, chaga is unique for its high betulinic acid content, which the mushroom concentrates from the bark of the trees on which it grows3. Betulinic acid has demonstrated exceptional anti-cancer4,5,6,7,8,9,10,11,12,13 and anti-viral action14,15 in numerous studies. Regarded to have many beneficial health properties, chaga has been shown to have anti-inflammatory, anti-allergen, and antibacterial properties16. It has been used traditionally as a tonic, blood purifier, and pain-reliever17.
Chaga has a long history as a folk remedy for cancer in Poland and Russia, where it has legendary status for being able to treat a wide range of cancer types18. Chaga has been approved as an anti-cancer drug in Russia under the name Befungin19.
Betulinic acid is the primary active component in chaga. A potent anti-tumor compound, betulinic acid shows high activity against a variety of cancer strains without toxicity20,21, and numerous studies cite it as a highly promising chemotherapeutic agent22,23.
Certain chemotherapeutic drugs, called topoisomerase inhibitors, work by interfering with cancer cells’ eukaryotic topoisomerases, the enzymes that wind and unwind DNA. Betulinic acid has been found to be a potent inhibitor of eukaryotic topoisomerase, suggesting its potential in the design of anti-cancer drugs24.
Several studies have shown betulinic acid effective against melanoma25,26 where it strongly and consistently suppressed the growth and colony-forming ability of melanoma cell lines, and showed promise in combination with radiotherapy27,28. In neuroblastoma, betulinic acid directly destroyed cancer cells via apoptosis29. Additional studies have been conducted with cervical cancer, carcinoma, and malignant brain tumors, with promising results30,31.
A study with human hepatoma cancer cell lines found that chaga induced anti-proliferative and apoptic effects in a dose-dependant manner, meaning it both prevented the growth of new cancer cells and killed existing ones, with the anti-cancer activity increasing relative to the dose32.
Betulinic acid is a powerful anti-viral. Studies have found that it disrupts viral fusion to cells, including disrupting the assembly of budding HIV virus33. In a study with the influenza virus, chaga exerted 100% inhibition against all three influenza virus strains tested34.
Cited as a candidate for the development of new anti-malarial drugs, betulinic acid has been found to reduce malaria parasitemia in animal studies35.
One study comparing chaga to other mushrooms found it to have the highest anti-oxidant activity, demonstrating superior free radical scavenging36. Chaga extract protected cells against oxidative damage in vitro, reducing damage to human lymphocyte cells by 40% in one study37. Among other antioxidant components, the melanin complex in chaga has demonstrated very high antioxidant and genoprotective properties, making it a promising ingredient in the development of anti-carcinogens38.
1 Stamets, Paul, and C. Dusty Wu Yao. Mycomedicinals: An informational treatise on mushrooms. MycoMedia, 2002.
2 Bisko, Nina A., Nadezda Yu Mitropolskaya, and Natalia V. Ikonnikova. Melanin complex from medicinal mushroom Inonotus obliquus (Pers.: Fr.) Pilat (Chaga) (Aphyllophoromycetideae). International Journal of Medicinal Mushrooms 4.2 (2002).
3 Powell, M., 2010. Medicinal Mushrooms: A Clinical Guide, Mycology Press, East Sussex U.K.
4 Chowdhury, Arnab Roy, et al. Betulinic acid, a potent inhibitor of eukaryotic topoisomerase I: identification of the inhibitory step, the major functional group responsible and development of more potent derivatives. Medical Science Monitor 8.7 (2002): BR254-BR265.
5 Pisha, Emily, et al. Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis. Nature medicine 1.10 (1995): 1046-1051.
6 Bisko, Nina A., Nadezda Yu Mitropolskaya, and Natalia V. Ikonnikova. Melanin complex from medicinal mushroom Inonotus obliquus (Pers.: Fr.) Pilat (Chaga) (Aphyllophoromycetideae). International Journal of Medicinal Mushrooms 4.2 (2002).
7 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
8 Chowdhury, Arnab Roy, et al. Betulinic acid, a potent inhibitor of eukaryotic topoisomerase I: identification of the inhibitory step, the major functional group responsible and development of more potent derivatives. Medical Science Monitor 8.7 (2002): BR254-BR265.
9 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
10 Pisha, Emily, et al. Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis. Nature medicine 1.10 (1995): 1046-1051.
11 Schmidt, M. L., et al. Betulinic acid induces apoptosis in human neuroblastoma cell lines. European Journal of Cancer 33.12 (1997): 2007-2010.
12 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
13 Burczyk, J., et al. Antimitotic activity of aqueous extracts of Inonotus obliquus. Bollettino chimico farmaceutico 135.5 (1996): 306-309.
14 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
15 Kahlos, K., et al. Preliminary tests of antiviral activity of two Inonotus obliquus strains. Fitoterapia 67.4 (1996): 344-347.
16 Park, Yoo Kyoung, et al. Chaga mushroom extract inhibits oxidative DNA damage in human lymphocytes as assessed by comet assay. Biofactors 21.1 (2004)
17 Hobbs, Christopher. Medicinal mushrooms: an exploration of tradition, healing & culture. No. Ed. 2. Botanica Press, 1995.
18 Hobbs, Christopher. Medicinal mushrooms: an exploration of tradition, healing & culture. No. Ed. 2. Botanica Press, 1995.
19 Stamets, Paul, and C. Dusty Wu Yao. Mycomedicinals: An informational treatise on mushrooms. MycoMedia, 2002.p 33
20 Chowdhury, Arnab Roy, et al. Betulinic acid, a potent inhibitor of eukaryotic topoisomerase I: identification of the inhibitory step, the major functional group responsible and development of more potent derivatives. Medical Science Monitor 8.7 (2002): BR254-BR265.
21 Pisha, Emily, et al. Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis. Nature medicine 1.10 (1995): 1046-1051.
22 Bisko, Nina A., Nadezda Yu Mitropolskaya, and Natalia V. Ikonnikova. Melanin complex from medicinal mushroom Inonotus obliquus (Pers.: Fr.) Pilat (Chaga) (Aphyllophoromycetideae). International Journal of Medicinal Mushrooms 4.2 (2002).
23 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
24 Chowdhury, Arnab Roy, et al. Betulinic acid, a potent inhibitor of eukaryotic topoisomerase I: identification of the inhibitory step, the major functional group responsible and development of more potent derivatives. Medical Science Monitor 8.7 (2002): BR254-BR265.
25 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
26 Pisha, Emily, et al. Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis. Nature medicine 1.10 (1995): 1046-1051.
27 Selzer, Edgar, et al. Effects of betulinic acid alone and in combination with irradiation in human melanoma cells. Journal of investigative dermatology 114.5 (2000): 935-940.
28 Eder-Czembirek, Christina, et al. Betulinic acid a radiosensitizer in head and neck squamous cell carcinoma cell lines. Strahlentherapie und Onkologie 186.3 (2010): 143-148.
29 Schmidt, M. L., et al. Betulinic acid induces apoptosis in human neuroblastoma cell lines. European Journal of Cancer 33.12 (1997): 2007-2010.
30 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
31 Burczyk, J., et al. Antimitotic activity of aqueous extracts of Inonotus obliquus. Bollettino chimico farmaceutico 135.5 (1996): 306-309..
32 Youn, Myung-Ja, et al. Chaga mushroom (Inonotus obliquus) induces G0/G1 arrest and apoptosis in human hepatoma HepG2 cells. World Journal of Gastroenterology: WJG 14.4 (2008): 511.
33 Cichewicz, Robert H., and Samir A. Kouzi. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection. Medicinal research reviews 24.1 (2004): 90-114.
34 Kahlos, K., et al. Preliminary tests of antiviral activity of two Inonotus obliquus strains. Fitoterapia 67.4 (1996): 344-347.
35 de Sá, Matheus Santos, et al. Antimalarial activity of betulinic acid and derivatives in vitro against Plasmodium falciparum and in vivo in P. berghei-infected mice. Parasitology research 105.1 (2009): 275-279.
36 Nakajima, Yuki, Yuzo Sato, and Tetsuya Konishi. Antioxidant small phenolic ingredients in Inonotus obliquus (persoon) Pilat (Chaga). Chemical and Pharmaceutical Bulletin 55.8 (2007): 1222-1226.
37 Park, Yoo Kyoung, et al. Chaga mushroom extract inhibits oxidative DNA damage in human lymphocytes as assessed by comet assay. Biofactors 21.1 (2004): 109-112.
38 Bisko, Nina A., Nadezda Yu Mitropolskaya, and Natalia V. Ikonnikova. Melanin complex from medicinal mushroom Inonotus obliquus (Pers.: Fr.) Pilat (Chaga) (Aphyllophoromycetideae). International Journal of Medicinal Mushrooms 4.2 (2002).
Research
1. Melanin complex from medicinal mushroom Inonotus obliquus (Pers.: Fr.) Pilat (Chaga) (Aphyllophoromycetideae)
Bisko, N., et al. International Journal of Medicinal Mushrooms.
DOI: 10.1615/IntJMedMushr.v4.i2.70
In this study, researchers looked at the production of melanin complex in the mushroom Inonotus obliquus. They learned that it is induced by exposure to copper ions, pyrocatechol (a natural organic compound), and the amino acid tyrosine. Researchers learned that the melanin in this mushroom is comprised of carbon, hydrogen, and a small amount of nitrogen. Further investigation revealed that it has antioxidant and genoprotective activity in vitro. Researchers conclude that the melanin in Inonotus obliquus may have potential in the fight against cancer.
2. Chaga mushroom (Inonotus obliquus) induces G0/G1 arrest and apoptosis in human hepatoma HepG2 cells
Youn, M.J., et al. World Journal of Gastroenterology. 2008. 14 (4), 511-517.
In this in vitro study, researchers examined the effects of an extract of the chaga mushroom on two different lines of human liver cancer cells. Various tests revealed that the HepG2 cell line was more responsive than the Hep3B cell line, showing a greater reduction in cell survival. The greater the dose, the greater the response. The extract caused cells to become inactive and stimulated apoptosis. Researchers conclude that the chaga mushroom has potential benefit in the treatment of liver cancer.
3. Antioxidant small phenolic ingredients in Inonotus obliquus (persoon) Pilat (Chaga)
Nakajima, Y., et al. Chemical and Pharmaceutical Bulletin. 2007. 55 (8), 1222-1226.
Researchers prepared a hot water extract of Inonotus obliquus (chaga) and compared its antioxidant activity to that of three other mushrooms. Chaga demonstrated superior superoxide and hydroxyl radical scavenging activity. Researchers discovered that an extract of one part of the mushroom (the brown “fruiting body”) had greater antioxidant activity than the sclerotium, another part of the mushroom. Researchers also identified and isolated seven phenolic compounds present in chaga.
4. Chaga mushroom extract inhibits oxidative DNA damage in human lymphocytes as assessed by comet assay
Park, Y.K., et al. BioFactors. 2004. 21 (1-4), 109-112.
Researchers theorized that the beneficial effects of the chaga mushroom may be associated with protection against free radical damage. In this in vitro experiment, human white blood cells were treated with chaga mushroom extracts of varying strengths. The cells were then exposed to oxidative stress, and the results were examined. The cells that were treated with the extract had significantly less damage compared to controls.
5. Betulinic acid, a potent inhibitor of eukaryotic topoisomerase I: identification of the inhibitory step, the major functional group responsible and development of more potent derivatives
Chowdhury, A.R., et al. Medical Science Monitor. 2002. 8 (7), 254-265.
Researchers looked at the effects of betulinic acid, a compound found in chaga mushrooms, on eukaryotic topoisomerase I, an enzyme that regulates the structure of DNA. Using various testing methods, they discovered the mechanisms by which betulinic acid inhibits this enzyme. The findings are significant and have applications in the development of anti-tumor treatments.
6. Antimalarial activity of betulinic acid and derivatives in vitro against Plasmodium falciparum and in vivo in P. berghei-infected mice
Santos de Sa, M., et al. Parasitology Research. 2009. 105 (1), 275-279.
In this series of experiments, researchers looked at the effects of betulinic acid on malaria in mice. Betulinic acid is a naturally occurring compound in chaga mushrooms and other plant life; researchers looked at it and four of its derivative compounds. All the substances were effective in vitro against Plasmodium parasites (which cause malaria). Mice were infected with Plasmodium and given the derivative betulinic acid acetate. In a dose dependent manner, the betulic acid acetate reduced blood levels of Plasmodium. Researchers conclude that betulinic acid and its derivatives show potential as possible anti-malarial treatment.
7. Betulinic acid induces apoptosis in human neuroblastoma cell lines
Schmidt, M.L., et al. European Journal of Cancer. 1997. 33 (12), 2007-2010.
Researchers looked at the effects of betulinic acid, a compound found in chaga mushrooms and other plant life, on human neuroblastoma cells. (Neuroblastomas are tumors comprised of neuroblasts, and are most commonly found in the adrenal glands.) Nine cell lines were treated with betulinic acid in varying strengths for durations of up to six days. Within three days, changes in the cell structure were evident. The observed structural changes were consistent with cell death. Researchers conclude that further study is warranted.
8. Chemistry, biological activity, and chemotherapeutic potential of betulinic acid for the prevention and treatment of cancer and HIV infection
Cichewicz, R.H. and Kouzi, S.A. Medicinal Research Reviews. 2004. 24 (1), 90-114.
In this review article, the authors discuss the many beneficial effects of betulinic acid, a naturally occurring plant compound. It is a recognized anti-inflammatory, anti-tumoric, and has demonstrated anti-malarial effect in vitro. Of particular interest is its anti-HIV-1 activity. Studies have shown that not only betulinic acid, but also its derivatives, has therapeutic benefit for HIV patients. The derivatives work in several different ways to fight the HIV virus. Betulinic acid also shows potential as an anti-cancer agent, with proven effectiveness in vitro against several types of cancer cells. Betulinic acid is considered safe in high doses.
9. Betulinic acid: a new cytotoxic agent against malignant brain-tumor cells
Fulda, S., et al. International Journal of Cancer. 1999. 82 (3), 435-441.
In this in vitro study, researchers looked at the effectiveness of betulinic acid (a naturally occurring compound found in plants and fungi such as the chaga mushroom) against brain cancer cells. Two types of brain cancer cell lines were evaluated: medullablastoma and glioblastoma. Betulinic acid was effective against both. Although the samples were small, betulinic acid was effective against 100% of primary medulloblastomoa tumor samples (from 4 patients), and 83% of primary glioblastoma tumor samples (from 24 patients). The mechanism of action is believed to be apoptosis via disruption of cell mitochondria. Researchers conclude that further study is warranted for the potential of betulinic acid in the treatment of brain cancers.
10. Effects of betulinic acid alone and in combination with irradiation in human melanoma cells
Selzer, E., et al. The Journal of Investigative Dermatology. 2000. 114, 935-940.
Researchers looked at the effects of betulinic acid (a compound found in plants, including chaga mushrooms) on cancer cells. Betulinic acid was used alone and in combination with radiation treatment. The betulinic acid significantly inhibited human melanoma cell growth and colonization, and was shown to induce apoptosis (cell death). When cells were irradiated, the betulinic acid had an additive effect; researchers believe the two types of treatment function in different ways. Researchers conclude that betulinic acid (either alone or combined with radiation therapy) has potential as a treatment for cancer.
11. Betulinic acid a radiosensitizer in head and neck squamous cell carcinoma cell lines
Eder-Czembirek, C., et al. Strahlentherapie und Onkologie. 2010. 186 (3), 143-148.
Researchers set out to examine the effects of betulinic acid with radiation therapy on two cancer cell lines. The cell lines were derived from human head and neck squamous cell carcinomas. The cell lines were treated with betulinic acid in varying doses and then subjected to radiation treatment. The cells were then evaluated for survival rates and their ability to form colonies. Researchers made three observations: betulinic acid inhibited cell survival by itself; it inhibited colony-forming ability of cancer cells by itself; and it had an additive effect when used in conjunction with radiation. Researchers believe that in head and neck cancers that do not respond well to radiation, betulinic acid offers an effective alternative. Combination therapy also shows potential.
12. Antitumor and hypoglycemic activities of polysaccharides from the sclerotia and mycelia of Inonotus obliquus (Pers.: Fr.) Pil. (Aphyllophoromycetideae)
Takashi, M., et al. International Journal of Medicinal Mushrooms.
DOI: 10.1615/IntJMedMushr.v1.i4.20
Researchers examined the effects of polysaccharides from chaga mushrooms on certain enzymes related to the cell cycle and cancer formation, and on blood sugar levels. Researchers determined that the polysaccharides did help inhibit the enzymes, thus suggesting a potential role in cancer prevention. The polysaccharides also had hypoglycemic effects lasting up to 48 hours. The active compounds were identified as beta glucan and heteroglucan.
13. Antimitotic activity of aqueous extracts of Inonotus obliquus
Burczyk, J., et al. Bollettino Chimico Farmaceutico. 1996. 135 (5), 306-309.
In this in vitro study, researchers evaluated the effects of two extracts of chaga mushroom on human cervical cancer cells. Cells were treated with concentrations of the extract ranging from 10 to 2000 micrograms/ml. Regardless of the strength of the extract, cancer cell growth was suppressed. Researchers noted that the extract interfered with mitosis and interrupted normal cell cycles.
14. Preliminary tests of antiviral activity of two Inonotus obliquus strains
Kahlos, K., et al. Fitoterapia. 1996. 67 (4), 344-347.
Researchers looked at the antiviral effects of Inonotus obliquus (chaga mushroom) grown on alder and birch trees. The mushroom was tested on human influenza A and B and four different strains of horse influenza. Researchers learned that one part of the mushroom (the black surface area) that was grown on birch (as opposed to alder) was the most effective; it completely suppressed all the viruses tested. Researchers believe the active compounds are betulin, lupeol, and mycosterols.
15. Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis
Pisha, E., et al. Nature Medicine. 1995. 1 (10), 1046-1051.
Researchers used bioassay-guided fractionation to identify betulinic acid, found in chaga mushrooms and other plant life, as an anti-tumoric compound. Experiments involving mice demonstrated that betulinic acid suppresses melanoma tumors without damaging healthy cells. Further study revealed that the mechanism of action was apoptosis. Researchers conclude that betulinic acid shows promise in the treatment of melanoma.
