Chaga mushroom is a black perennial fungus that usually parasites on adult birch tree trunks. It has been conventionally used as a health-promoting supplement and nutraceutical in different cultures for centuries. The desired clarification of the profile of chaga secondary metabolites responsible for various bioactive properties has been continuously pursued for decades but has only partially been unveiled. Meanwhile, in recent years, attention to food safety, quality stability, authentication, and sustainability of chaga products from the wild has become increasingly popular in the current commercial market and related small/medium-size food industry enterprises. Phenolic, hydroxylated fatty acid, and terpenoid compounds produced by sclerotia of chaga mushrooms are bioactive constituents with antioxidant, anti-microorganism, and anti-tumor activities. Some new secondary metabolites of chaga mushroom have occasionally been reported previously, and effects of environment (e.g., cultivation method, harvesting region) on compositional characteristics noted. However, these have rarely and systematically compared the compositions of their material with a reliable database of known secondary metabolites of chaga. Therefore, this study aimed to achieve a rapid screening and characterization of secondary metabolites of Newfoundland chaga. A total of 111 phenolic, 63 fatty/aromatic acid, and 108 terpenoid constituents was primarily identified using HPLC-ToF-MS (high-performance liquid chromatograph coupled with time-of-flight mass spectra), among which 161 were newly reported. In addition, an update of the compositional database of chaga was provided as supplementary materials to help utilization and development of Newfoundland chaga mushroom as edible-fungi. Conclusively, chaga mushroom is a very promising food supplement abundant in numerous fungal secondary metabolites that were rarely found in other edible materials, even though its safety (e.g., oxalate content) aspects is still in need of additional investigation for being considered as a viable commercial nutraceutical.
Abu-Reidah, I.M., Critch, A.L., Manful, C.F., Rajakaruna, A., Vidal, N.P., Pham, T.H., Cheema, M., and Thomas, R. (2021). Effects of pH and temperature on water under pressurized conditions in the extraction of nutraceuticals from chaga (Inonotus obliquus) mushroom. Antioxidants 10(8): 1322.
Babitskaya, V.G., Scherba, V.V., Ikonnikova, N.V., Bisko, N.A., and Mitropolskaya, N.Y. (2002). Melanin complex from medicinal mushroom Inonotus obliquus (Pers.: Fr.) Pilat (Chaga)(Aphyllophoromycetidae). Int. J. Med. Mushrooms 4: 139–145.
Baek, J., Roh, H.-S., Baek, K.-H., Lee, S., Lee, S., Song, S.-S., and Kim, K.H. (2018). Bioactivity-based analysis and chemical characterization of cytotoxic constituents from Chaga mushroom (Inonotus obliquus) that induce apoptosis in human lung adenocarcinoma cells. J. Ethnopharmacol. 224: 63–75.
Chang, Y., Bai, M., Xue, X.-B., Zou, C.-X., Huang, X.-X., and Song, S.-J. (2022). Isolation of chemical compositions as dietary antioxidant supplements and neuroprotectants from Chaga mushroom (Inonotus obliquus). Food Biosci. 47: 101623.
Géry, A., Dubreule, C., André, V., Rioult, J.-P., Bouchart, V., Heutte, N., Eldin de Pécoulas, P., Krivomaz, T., and Garon, D. (2018). Chaga (Inonotus obliquus), a future potential medicinal fungus in oncology? A chemical study and a comparison of the cytotoxicity against human lung adenocarcinoma cells (A549) and human bronchial epithelial cells (BEAS-2B). Integr. Cancer Ther. 17(3): 832–843.
Glamočlija, J., Ćirić, A., Nikolić, M., Fernandes, Â., Barros, L., Calhelha, R.C., Ferreira, I.C., Soković, M., and Van Griensven, L.J. (2015). Chemical characterization and biological activity of Chaga (Inonotus obliquus), a medicinal “mushroom”. J. Ethnopharmacol. 162: 323–332.
Handa, N., Yamada, T., and Tanaka, R. (2010). An unusual lanostane-type triterpenoid, spiroinonotsuoxodiol, and other triterpenoids from Inonotus obliquus. Phytochemistry 71(14-15): 1774–1779.
He, J., Feng, X.-Z., Lu, Y., and Zhao, B. (2001). Three new triterpenoids from Fuscoporia obliqua. J. Asian Nat. Prod. Res. 3(1): 55–61.
Hwang, B.S., Lee, I.-K., and Yun, B.-S. (2016). Phenolic compounds from the fungus Inonotus obliquus and their antioxidant properties. J. Antibiot. 69(2): 108–110.
Ju, H.K., Chung, H.W., Hong, S.-S., Park, J.H., Lee, J., and Kwon, S.W. (2010). Effect of steam treatment on soluble phenolic content and antioxidant activity of the Chaga mushroom (Inonotus obliquus). Food Chem. 119(2): 619–625.
Ka, K.-H., Jeon, S.-M., Park, H., Lee, B.-H., and Ryu, S.-R. (2017). Growth of Chaga Mushroom (Inonotus obliquus) on Betula platyphylla var. japonica. Korean J. Mycol. 45(3): 241–245.
Kahlos, K., Hintsanen, E., Seppänen-Laakso, T., and Hiltunen, R. (1989). Lipid compounds of three species of cultivated Inonotus. Planta Med. 55(07): 621–622.
Kim, M.-Y., Seguin, P., Ahn, J.-K., Kim, J.-J., Chun, S.-C., Kim, E.-H., Seo, S.-H., Kang, E.-Y., Kim, S.-L., and Park, Y.-J. (2008). Phenolic compound concentration and antioxidant activities of edible and medicinal mushrooms from Korea. J. Agric. Food Chem. 56(16): 7265–7270.
Kim, Y.J., Park, J., Min, B.S., and Shim, S.H. (2011). Chemical constituents from the sclerotia of Inonotus obliquus. J. Korean Soc. Appl. Biol. Chem. 54(2): 287–294.
Kou, R.-W., Han, R., Gao, Y.-Q., Li, D., Yin, X., and Gao, J.-M. (2021). Anti-neuroinflammatory polyoxygenated lanostanoids from Chaga mushroom Inonotus obliquus. Phytochemistry 184: 112647.
Koyama, T., Gu, Y., and Taka, A. (2008). Fungal medicine, Fuscoporia obliqua, as a traditional herbal medicine: its bioactivities, in vivo testing and medicinal effects. Asian Biomed. 2(6): 459–469.
Kwon, O., Kim, Y., Paek, J.H., Park, W.Y., Han, S., Sin, H., and Jin, K. (2022). Chaga mushroom-induced oxalate nephropathy that clinically manifested as nephrotic syndrome: A case report. Medicine 101(10): e28997.
Lee, I.-K., Kim, Y.-S., Jang, Y.-W., Jung, J.-Y., and Yun, B.-S. (2007). New antioxidant polyphenols from the medicinal mushroom Inonotus obliquus. Bioorganic Med. Chem. Lett. 17(24): 6678–6681.
Lee, I.-K., and Yun, B.-S. (2011). Styrylpyrone-class compounds from medicinal fungi Phellinus and Inonotus spp., and their medicinal importance. J. Antibiot. 64(5): 349–359.
Lee, S., Lee, H.Y., Park, Y., Ko, E.J., Ban, T.H., Chung, B.H., Lee, H.S., and Yang, C.W. (2020). Development of End Stage Renal Disease after Long-Term Ingestion of Chaga Mushroom: Case Report and Review of Literatures. J. Korean Med. Sci. 35(19): e122.
Lemieszek, M.K., Langner, E., Kaczor, J., Kandefer-Szerszen, M., Sanecka, B., Mazurkiewicz, W., and Rzeski, W. (2011). Anticancer effects of fraction isolated from fruiting bodies of Chaga medicinal mushroom, Inonotus obliquus (Pers.: Fr.) Pilát (Aphyllophoromycetideae): in vitro studies. Int. J. Med. Mushrooms 13(2): 131–43.
Liu, C., Zhao, C., Pan, H.-H., Kang, J., Yu, X.-T., Wang, H.-Q., Li, B.-M., Xie, Y.-Z., and Chen, R.-Y. (2014). Chemical constituents from Inonotus obliquus and their biological activities. J. Nat. Prod. 77(1): 35–41.
Mazurkiewicz, W. (2006). Analysis of aqueous extract of Inonotus obliquus. Drug Res. 4(8): 9.
Nakajima, Y., Sato, Y., and Konishi, T. (2007). Antioxidant small phenolic ingredients in Inonotus obliquus (persoon) Pilat (Chaga). Chem. Pharm. Bull. 55(8): 1222–1226.
Peng, H., and Shahidi, F. (2020). Bioactive compounds and bioactive properties of Chaga (Inonotus obliquus) mushroom: A review. J. Food Bioact. 12: 9–75.
Reid, D. (1976). Inonotus obliquus (pers. Ex Fr.) pilat in Britain. Trans. Brit. Mycol. Soc. 67(2): 329–332.
Saar, M. (1991). Fungi in Khanty folk medicine. J. Ethnopharmacol. 31(2): 175–179.
Shashkina, M.Y., Shashkin, P., and Sergeev, A. (2006). Chemical and medicobiological properties of chaga. Pharm. Chem. J. 40(10): 560–568.
Shcherbakov, D., Kukina, T., Elshin, I., Panteleeva, N., Teplyakova, T., and Salnikova, O. (2022). GC-MS analysis of lipophilic Chaga mushroom constituents. AIP Conf. Proc. 2390: 030083.
Shikov, A.N., Pozharitskaya, O.N., Makarov, V.G., Wagner, H., Verpoorte, R., and Heinrich, M. (2014). Medicinal Plants of the Russian Pharmacopoeia; their history and applications. J. Ethnopharmacol. 154: 520.
Shin, Y., Tamai, Y., and Terazawa, M. (2000). Chemical Constituents of Inonotus obliquus Ⅰ.: A new triterpene, 3β-hydroxy-8, 24-dien-lanosta-21, 23-lactone from sclerotium. Eurasian J. Forest Res. 1: 43–50.
Shin, Y., Tamai, Y., and Terazawa, M. (2001). Chemical Constituents of Inonotus obliquus Ⅳ.: Triterpene and Steroids from Cultured Mycelia. Eurasian J. Forest Res. 2: 27–30.
Sun, Y., Yin, T., Chen, X.-H., Zhang, G., Curtis, R.B., Lu, Z.-H., and Jiang, J.-H. (2011). In vitro antitumor activity and structure characterization of ethanol extracts from wild and cultivated Chaga medicinal mushroom, Inonotus obliquus (Pers.: Fr.) Pilát (Aphyllophoromycetideae). Int. J. Med. Mushrooms 13(2): 121–130.
Taji, S., Yamada, T., and Tanaka, R. (2008a). Three new lanostane triterpenoids, inonotsutriols A, B, and C, from Inonotus obliquus. Helv. Chim. Acta 91(8): 1513–1524.
Taji, S., Yamada, T., In, Y., Wada, S.i., Usami, Y., Sakuma, K., and Tanaka, R. (2007). Three new lanostane triterpenoids from Inonotus obliquus. Helv. Chim. Acta 90(11): 2047–2057.
Taji, S., Yamada, T., Wada, S.-I., Tokuda, H., Sakuma, K., and Tanaka, R. (2008b). Lanostane-type triterpenoids from the sclerotia of Inonotus obliquus possessing anti-tumor promoting activity. Eur. J. Med. Chem. 43(11): 2373–2379.
Wang, Q., Mu, H., Zhang, L., Dong, D., Zhang, W., and Duan, J. (2015). Characterization of two water-soluble lignin metabolites with antiproliferative activities from Inonotus obliquus. Int. J. Biol. Macromol. 74: 507–514.
Wold, C.W., Gerwick, W.H., Wangensteen, H., and Inngjerdingen, K.T. (2020). Bioactive triterpenoids and water-soluble melanin from Inonotus obliquus (Chaga) with immunomodulatory activity. J. Funct. Foods 71: 104025.
Wold, C.W., Kjeldsen, C., Corthay, A., Rise, F., Christensen, B.E., Duus, J.Ø., and Inngjerdingen, K.T. (2018). Structural characterization of bioactive heteropolysaccharides from the medicinal fungus Inonotus obliquus (Chaga). Carbohydr. Polym. 185: 27–40.
Ying, Y.-M., Zhang, L.-Y., Zhang, X., Bai, H.-B., Liang, D.-E., Ma, L.-F., Shan, W.-G., and Zhan, Z.-J. (2014). Terpenoids with alpha-glucosidase inhibitory activity from the submerged culture of Inonotus obliquus. Phytochemistry 108: 171–176.
Zhao, F., Mai, Q., Ma, J., Xu, M., Wang, X., Cui, T., Qiu, F., and Han, G. (2015a). Triterpenoids from Inonotus obliquus and their antitumor activities. Fitoterapia 101: 34–40.
Zhao, F., Xia, G., Chen, L., Zhao, J., Xie, Z., Qiu, F., and Han, G. (2016). Chemical constituents from Inonotus obliquus and their antitumor activities. J. Nat. Med. 70(4): 721–730.
Zhao, Y., Xi, Q., Xu, Q., He, M., Ding, J., Dai, Y., Keller, N.P., and Zheng, W. (2015b). Correlation of nitric oxide produced by an inducible nitric oxide synthase-like protein with enhanced expression of the phenylpropanoid pathway in Inonotus obliquus cocultured with Phellinus morii. Appl. Microbiol. Biotechnol. 99(10): 4361–4372.
Zheng, W., Miao, K., Liu, Y., Zhao, Y., Zhang, M., Pan, S., and Dai, Y. (2010). Chemical diversity of biologically active metabolites in the sclerotia of Inonotus obliquus and submerged culture strategies for up-regulating their production. Appl. Microbiol. Biotechnol. 87(4): 1237–1254.
Zheng, W., Zhang, M., Zhao, Y., Miao, K., Pan, S., Cao, F., and Dai, Y. (2011). Analysis of antioxidant metabolites by solvent extraction from sclerotia of Inonotus obliquus (Chaga). Phytochem. Anal. 22(2): 95–102.
Zheng, W., Zhang, M., Zhao, Y., Wang, Y., Miao, K., and Wei, Z. (2009). Accumulation of antioxidant phenolic constituents in submerged cultures of Inonotus obliquus. Bioresour. Technol. 100(3): 1327–1335.
Zheng, W., Zhao, Y.-X., Zhang, M., Yin, Z., Chen, C., and Wei, Z. (2008). Phenolic compounds from Inonotus obliquus and their immune stimulating effects. Mycosystema 27(4): 574–581.
Zheng, W.-F., Liu, T., Xiang, X., and Gu, Q. (2007). Sterol composition in field-grown and cultured mycelia of Inonotus obliquus. Acta Pharm. Sin. 42(7): 750–756.
Zhong, X.-H., Ren, K., Lu, S.-J., Yang, S.-Y., and Sun, D.-Z. (2009). Progress of research on Inonotus obliquus. Chin. J. Integr. Med. 15(2): 156–160.