## 3 Conclusions  
This review concludes that _Ganoderma_ contains various pharmacologically active triterpenoids and that GTs are one of the main described metabolic constituents with different structural types, which are related to the diverse range of biological activities. According to the GTs reported from 1984 to 2022, we found that 8,9-ene ganoderma acid and 7,9(11)-diene ganoderma alcohol showed significant anti-HIV-1, anti-HIV-1 protease and cytotoxic activities, laying a foundation for further investigations of bioactive analyses. The main ganoderma acid and ganoderma alcohol can be isolated from _Ganoderma_, which suggested that GTs can be used for the control of various diseases. In addition, different species of _Ganoderma_ possessed some specific lanostane triterpenoid, and some novel skeletons only appeared in specific species. Meanwhile, the diversity of _Ganoderma_ species mainly reveals morphological differences, which were related to the geographic position and biotic environment. However, these conditions led to the production of different types of GTs. In other words, the types of GTs may influence the morphology of _Ganoderma_. Furthermore, the biosynthetic pathway of GTs has been proven at the gene level. Thus, the relationship of the types of GTs and morphology could be verified through further gene analyses [142; 317; 318; 319; 320].  
_Ganoderma_ triterpenoids are structurally and stereochemically complex small molecules. In addition, each of these compounds possesses sites of diversification, allowing for the facile and rapid creation of dozens of complex compounds for drug screening. In recent years, researchers have focused on GTs and their broad spectrum of bioactivities. Natural products are typically complex molecules that have enjoyed notable success in drug discovery [321; 322; 323; 324]. Here, the crucial tasks include the completion of clinical trials and the elaboration of high-quality _Ganoderma_ spp. derived products with sustainable production via standard procedures.  
Currently, the _Ganoderma_ industry earns billions of dollars via cultivation or wild collections, consumption as tea or alcoholic beverages and the use of nutraceuticals, with the industry offering thousands of products to the markets [325; 326; 327]. With great potential for the _Ganoderma_ market and industry, it is becoming increasingly essential that the active ingredients such as GTs are identified. This will help enhance existing market trends and future _Ganoderma_ industry growth in terms of both value and volume. Although _Ganoderma_ triterpenoids are found to be one of the main bioactive constituents, more attention should be paid in future studies in order to detect other bioactive compounds.  
**Author Contributions:** Supervision, S.R. and S.C.K.; Writing--original draft preparation, M.C.A.G., N.M.P. and S.C.K.; writing--review and editing, M.C.A.G., N.M.P, B.M.P, K.K.H., N.S., D.-Q.D., S.T., S.R. and S.C.K. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by the National Natural Science Foundation of China, grant number NSFC 31760013, 31950410558 and 32260004, and High-Level Talent Recruitment Plan of Yunnan Province (\"Young Talents\" Program). The authors extend their appreciation to Chiang Mai University for financial support.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Not applicable.  
**Acknowledgments:** The authors are grateful to Qujing Normal University and Chiang Mai University. Kalani K. Hapuarachchi thanks Tingchi-Wen, Guizhou University, Guiyang, China, for his support and guidance.  
**Conflicts of Interest:** The authors declare no conflict of interest.