Meroterpenoids from the Fungus Ganoderma sinensis and First Absolute Configuration Clarification of Zizhine H

Insights into Ganoderma fungi meroterpenoids opening a new era of racemic natural products in mushrooms

Ganoderma meroterpenoids (GMs) containing 688 structures to date were discovered to have multiple remarkable biological activities. 65.6% of meroterpenoids featuring stereogenic centers from Ganoderma species are racemates. Further, GMs from different Ganoderma species seem to have their own characteristics. In this review, a comprehensive summarization of GMs since 2000 is presented, including GM structures, structure corrections, biological activities, physicochemical properties, total synthesis, and proposed biosynthetic pathways. Additionally, we especially discuss the racemic nature, species-related structural distribution, and structure-activity relationship of GMs, which will provide a likely in-house database and shed light on future studies on GMs.

Structural diversity, hypothetical biosynthesis, chemical synthesis, and biological activity of Ganoderma meroterpenoids

Covering: 2018 to 2022Meroterpenoids found in fungal species of the genus Ganoderma and known as Ganoderma meroterpenoids (GMs) are substances composed of a 1,2,4-trisubstituted benzene and a polyunsaturated side chain. These substances have attracted the attention of chemists and pharmacologists due to their diverse structures and significant bioactivity. In this review, we present the structures and possible biosynthesis of representative GMs newly found from 2018 to 2022, as well as chemical synthesis and biological activity of some interesting GMs. We propose for the first time a plausible biosynthetic pathway for GMs, which will certainly motivate further research on the biosynthetic pathway in Ganoderma species, as well as on chemical synthesis of GMs as important bioactive compounds for the purpose of drug development.

Isolation and Characterization of trans‐p‐ Hydroxycinnamoyl Meroterpenoids from Ganoderma sinensis

Zizhines V, W, Y, Z, (±)-zizhines X, and Z1-Z3, and (±)-ganosinensol L, thirteen new compounds including four pairs of enantiomers and a known compound (-)-ganosinensol L, were isolated from the fruiting bodies of Ganoderma sinensis. Their structures were identified by spectroscopic, computational methods, and CD (circular dichroism spectroscopy) comparisons. Zizhines V-Z and Z1-Z3 are meroterpenoids consisting of the phenolic and the terpenoidal parts. All the compounds except zizhine Z3 bear a common trans-p-hydroxycinnamoyl group. Biological evaluation shows that (-)-zizhine Z1 inhibits cell migration in the MDA-MB-231 cell lines. The present study discloses the chemical profiling of G. sinensis and paves the way for its development as functional products to benefit chronic disorders.

Meroterpenoids containing benzopyran or benzofuran motif from Ganoderma cochlear

Five undescribed benzopyran containing meroterpenoids, ganodercins Q－U, two undescribed benzofuran containing meroterpenoids, ganodercins V and W, and two known meroterpenoids were isolated from Ganoderma cochlear. Their structures were elucidated by using HRESIMS, NMR spectroscopy and computational methods. The results of biochemical studies using a palmitic acid (PA) induced insulin resistance (IR) model show that (-)-ganodercin Q, (+)-ganodercins R and W activate phospho-AKT (p-AKT) at 20 μM and improve glucose uptake in a concentration dependent manner. The results of renoprotection studies show that (+)-ganodercin S, cochlearol F, (+)- and (-)-ganodercins V reduce the expression of collagen I.

The chemistry and biology of fungal meroterpenoids (2009-2019)

Fungal meroterpenoids are secondary metabolites from mixed terpene-biosynthetic origins. Their intriguing chemical structural diversification and complexity, potential bioactivities, and pharmacological significance make them attractive targets in natural product chemistry, organic synthesis, and biosynthesis. This review provides a systematic overview of the isolation, chemical structural features, biological activities, and fungal biodiversity of 1585 novel meroterpenoids from 79 genera terrestrial and marine-derived fungi including macrofungi, Basidiomycetes, in 441 research papers in 2009-2019. Based on the nonterpenoid starting moiety in their biosynthesis pathway, meroterpenoids were classified into four categories (polyketide-terpenoid, indole-, shikimate-, and miscellaneous-) with polyketide-terpenoids (mainly tetraketide-) and shikimate-terpenoids as the primary source. Basidiomycota produced 37.5% of meroterpenoids, mostly shikimate-terpenoids. The genera of Ganoderma, Penicillium, Aspergillus, and Stachybotrys are the four dominant producers. Moreover, about 56% of meroterpenoids display various pronounced bioactivities, including cytotoxicity, enzyme inhibition, antibacterial, anti-inflammatory, antiviral, antifungal activities. It's exciting that several meroterpenoids including antroquinonol and 4-acetyl antroquinonol B were developed into phase II clinically used drugs. We assume that the chemical diversity and therapeutic potential of these fungal meroterpenoids will provide biologists and medicinal chemists with a large promising sustainable treasure-trove for drug discovery.

Lucidumones B-H, racemic meroterpenoids that inhibit tumor cell migration from Ganoderma lucidum

Seven new meroterpenoids, lucidumones B-H (1 and 3-8), along with one known meroterpenoid (2), were isolated from the fruiting bodies of Ganoderma lucidum. The structures of the new compounds were assigned by spectroscopic and computational methods. All the isolated compounds were tested for their inhibition on human cancer cell migration. It was found that compounds (-)-1, (+)-2, (-)-4, (+)-6, and (+)-8 could significantly inhibit cell migration in KYSE30 cell line. Further examination disclosed that cell migration inhibition of (+)-6 and (+)-8 might be related with downregulation of N-cadherin.

Gancochlearols E - I, meroterpenoids from Ganoderma cochlear against COX-2 and triple negative breast cancer cells and the absolute configuration assignment of ganomycin K

Five new meroterpenoids, gancochlearols E - I (1, 3-6), and one compound ganomycin K (2) were isolated from the fruiting bodies of G. cochlear. Their structures were assigned by 1D and 2D NMR, MS, and CD analysis. Rh₂(OCOCF₃)₄-induced ECD method was used to clarify the absolute configuration of secondary alcohol in 1 and 2. Biochemical evaluation showed that all the isolates significantly inhibit COX-2 enzyme in vitro with the IC₅₀ values range from 1.03 μM to 2.71 μM. Further cellular assay revealed that (+)-3 and (-)-6 could suppress metastatic phenotype of triple-negative breast cancer (TNBC) cells via impeding the epithelial-mesenchymal transition (EMT).

Meroterpenoids produced by fungi: Occurrence, structural diversity, biological activities, and their molecular targets

Meroterpenoids are partially derived from the terpenoids, distributing widely in the plants, animals and fungi. The complex structures and diverse bioactivities of meroterpenoids have attracted more attention for chemists and pharmacologists. Since the first review summarized by Geris in 2009, there are absent of systematic reviews reported about meroterpenoids from the higher and lower fungi up to now. In the past decades, myriads of meroterpenoids were discovered, and it is necessary to summarize these meroterpenoids about their unique structures and promising bioactivities. In this review, we use a new classification method based on the non-terpene precursors, and also highlight the structural features, bioactivity of natural meroterpenoids from the higher and lower fungi covering the period of September 2008 to February 2020. A total of 709 compounds were discussed and cited the 182 references. Meanwhile, we also primarily summarize their occurrence, structural diversity, biological activities, and molecular targets.