Triterpenoids have consistently proven to be some of the most important constituents of functional, or medicinal, mushrooms, among the most popular species being Ganoderma lucidum (reishi), in addition to shiitake and maitake, all staples of natural medicine.
Considering the overwhelming variety of medicinal mushrooms with mysterious powers, scientists are aiming to zone in on individual triterpenes and learn more about their therapeutic potential.
In a study  that investigated triterpenoids in reishi mushrooms, five triterpenoids were isolated from the ether-soluble fraction of spores of the mushrooms: anopsoreric acid A, ganoderic acid B, ganoderic acid C1, ganoderic acid E, and ganodermanontriol.
Two new pentacyclic triterpenoids were also isolated from the spores—ganosporelactone A and B. Another two new lanostane-type triterpenes were extracted, lucidumol A and ganoderic acid β, along with a new natural one, lucidumol B. And several already known triterpenoids were isolated: ganodermanondiol, ganoderiol F, ganoderic acid A, ganolucidic acid A. 
“Of the compounds isolated, [ganodermanontriol], [lucidumol B], [ganodermanondiol], and [ganolucidic acid A] showed significant anti-human immunodeficiency virus (anti-HIV)-1 protease activity with IC50 values of 20-90 μM.” In other words, these triterpenes inhibited a protease essential for the replication of the HIV-1 virus.
Morever, six new highly oxygenated lanostane-type triterpenes were isolated: anoderic acid γ, ganoderic acid δ, ganoderic acid ε, ganoderic acid ξ, ganoderic acid η, ganoderic acid θ, together with ganolucidic acid D and ganoderic acid C2, again from the Ganoderma spores.
Ganoderic acids seem to be the most isolated triterpenes so far, with ganoderic acid A and B being the most well-known.  They have exhibited hepatoprotection (liver protection), antitumor effects, and 5-alpha reductase inhibition. [2,3]
Reishi’s triterpenes (alongside polysaccharides) inhibit growth and induce and/or fuel death of tumor cells. 
Reishi is a key source of ganoderic acids that have displayed anti-hepatitis B (a liver infection) activity and protective properties (in mice) against liver injury induced by bacteria, which could potentially translate to liver diseases in humans. 
With the development of extraction technologies, scientists will likely uncover more triterpenes and therapeutic benefits.
Image Credit: bluebirdprovisions / pixabay
- Ma B, et al. Triterpenoids from the spores of Ganoderma lucidum. N Am J Med Sci.2011 Nov; 3(11): 495–498, Impact Factor = 1.962; Times Cited = 18 (Semantic Scholar)
- Liu J, et al. Structure-activity relationship for inhibition of 5a-reductase by triterpenoids isolated from Ganoderma lucidum. Bioorganic & Medicinal Chemistry. 2006;14(24):8654-8660. Impact Factor = 3.073; Times Cited = 50 (Semantic Scholar)
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- Kao CHJ, et al. Anti-cancer activities of Ganoderma lucidum: active ingredients and pathways. Functional Foods in Health and Disease.2013;3(2):48-65. Impact Factor = n/a; Times Cited = 59 (Semantic Scholar)
- Li Y-Q, Wang S-F. Anti-hepatitis B activities of ganoderic acid from Ganoderma lucidum. Biotechnol Lett.2006;28:837-841. Impact Factor = 1.977; Times Cited = 55 (Semantic Scholar)