(±)-Ganoapplanin, a Pair of Polycyclic Meroterpenoid Enantiomers from Ganoderma applanatum

Total Synthesis of Ganoapplanin Enabled by a Radical Addition/Aldol Reaction Cascade

The total synthesis of the Ganoderma meroterpenoid ganoapplanin, an inhibitor of T-type voltage-gated calcium channels, is reported. Our synthetic approach is based on the convergent coupling of a readily available aromatic polyketide scaffold with a bicyclic terpenoid fragment. The three contiguous stereocenters of the terpenoid fragment, two of which are quaternary, were constructed by a diastereoselective, titanium-mediated iodolactonization. For the fusion of the two fragments and to simultaneously install the crucial biaryl bond, we devised a highly effective two-component coupling strategy. This event involves an intramolecular 6-exo-trig radical addition of a quinone monoacetal followed by an intermolecular aldol reaction. A strategic late-stage oxidation sequence allowed the selective installation of the remaining oxygen functionalities and the introduction of the characteristic spiro bisacetal structure of ganoapplanin.

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.

The Artist's Conk Medicinal Mushroom Ganoderma applanatum (Agaricomycetes): Mycological, Mycochemical, and Pharmacological Properties: A Review

As a commonly used Chinese herbal medicine, Ganoderma applanatum (Pers.) Pat., also known as flat-ling Ganoderma (Chinese name bianlingzhi), old mother fungus (laomujun), and old ox liver (laoniugan), has high medicinal value. It is used as an anti-cancer drug in China and Japan. Besides, it can treat rheumatic tuberculosis and has the effect of relieving pain, clearing away heat, eliminating accumulation, stopping bleeding and eliminating phlegm. The purpose of this review is to analyze the research progress systematically and comprehensively in mycology, mycochemistry and pharmacological activities of G. applanatum, and discuss the prospect of prospective research and implementation of this medicinal material. A comprehensive literature search was performed on G. applanatum using scientific databases including Web of Science, PubMed, Google Scholar, CNKI, Elsevier. Collected data from different sources was comprehensively summarized for mycology, mycochemistry and pharmacology of G. applanatum. A total of 324 compounds were recorded, the main components of which were triterpenoids, meroterpenoids, steroids, and polysaccharides. G. applanatum and its active ingredients have a variety of pharmacological effects, including anti-tumor, liver protection, hypoglycemic, anti-fat, anti-oxidation, antibacterial and other activities. Although G. applanatum is widely used in traditional medicine and has diverse chemical constituents, more studies should be carried out in animals and humans to evaluate the cellular and molecular mechanisms involved in its biological activity.

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.

Ganoaustralins A and B, Unusual Aromatic Triterpenes from the Mushroom Ganoderma australe

Two triterpenes, ganoaustralins A (1) and B (2), featuring unprecedented 6/6/6/5/6 scaffolds were isolated from the fruiting bodies of the mushroom Ganoderma australe. The structures were determined by extensive NMR and HRESIMS spectroscopic analysis. The absolute configuration of the C-25 in ganoaustralin A was assigned by the phenylglycine methyl ester (PGME) method. The relative and absolute configurations of the polycyclic backbones were determined by NMR and ECD calculations, respectively. The plausible biosynthetic pathways of ganoaustralins A and B were proposed. Ganoaustralin B showed weak inhibition against β-secretase 1.

Natural Enantiomers: Occurrence, Biogenesis and Biological Properties

The knowledge that natural products (NPs) are potent and selective modulators of important biomacromolecules (e.g., DNA and proteins) has inspired some of the world's most successful pharmaceuticals and agrochemicals. Notwithstanding these successes and despite a growing number of reports on naturally occurring pairs of enantiomers, this area of NP science still remains largely unexplored, consistent with the adage "If you don't seek, you don't find". Statistically, a rapidly growing number of enantiomeric NPs have been reported in the last several years. The current review provides a comprehensive overview of recent records on natural enantiomers, with the aim of advancing awareness and providing a better understanding of the chemical diversity and biogenetic context, as well as the biological properties and therapeutic (drug discovery) potential, of enantiomeric NPs.

Ganoderma applanatum mushroom provides new insights into the management of diabetes mellitus, hyperlipidemia, and hepatic degeneration: A comprehensive analysis

This study was undertaken to evaluate the antidiabetic, hypolipidemic, and hepatoprotective effects of methanol and aqueous extracts of Ganoderma applanatum (MEGA, AEGA) in alloxan-induced diabetic rats. The antidiabetic study was implemented by the induction of alloxan to the rats. The analysis of the hypolipidemic and liver-protective effects of fungus extracts was studied by estimating the lipid profile and the liver marker enzymes. Besides, in silico screening of the compounds of Ganoderma applanatum has been incorporated thus to check the binding affinity of compounds and enzymes affinity. The Discovery Studio 2020, UCSF Chimera, and PyRx AutoDock Vina have been used to implement the docking analysis. Nine days of oral feeding of MEGA and AEGA of Ganoderma applanatum resulted in a significant (p < .001) reduction in blood glucose, lipid profile, and liver marker enzymes. Besides, Myrocin C scored the highest score in the docking study. The biological and computational approaches suggested the MEGA and AEGA could be a potential source for antidiabetic, hypolipidemic, and hepatoprotective effects.

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.

CNS anti-depressant, anxiolytic and analgesic effects of Ganoderma applanatum (mushroom) along with ligand-receptor binding screening provide new insights: Multi-disciplinary approaches

This research was designed to evaluate the CNS depressant, anxiolytic, and analgesic action of aqueous and ethanol extract of Ganoderma applanatum, a valuable medicinal fungus used in multiple disorders belongs to Ganodermataceae family. Two extracts of G. applanatum were prepared using distilled water and ethanol as solvents and named AEGA and EEGA. Open field method, rotarod method, tail suspension method, and hole cross method were utilized for the CNS depressant action. In contrast, elevated plus-maze test and hole board method were utilized for the anxiolytic action. For determining the analgesic potential, acetic acid-induced writhing test, hot plate method, and tail immersion test were used. Besides, molecular docking has been implemented by using Discovery studio 2020, UCSF Chimera and PyRx autodock vina. At both doses (200 and 400 mg/kg) of AEGA and EEGA showed significant CNS depressant effect (p < 0.05 to 0.001) against all four tests used for CNS depressant activity. Both doses of AEGA and EEGA exhibited important anxiolytic activity effect (p < 0.05 to 0.001)against the EPM and hole board test. Both doses of AEGA and EEGA also exhibited a potential analgesic effect (p < 0.05 to 0.001) against all three tests used for analgesic action. In addition, in the molecular docking the compounds obtained the scores of −5.2 to −12.8 kcal/mol. Ganoapplanin, sphaeropsidin D and cytosporone C showed the best binding affinity to the selected recptors. It can be concluded that AEGA and EEGA have potential CNS depressant, anxiolytic, and analgesic action, which can be used as a natural antidepressant, anxiolytic, and analgesic source.

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The mushroom extracts were found to possess dose-dependent potentiality in antidepressant and anxiolytic test on mice model.

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The mushroom extracts revealed significant inhibition in pain.

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The mushroom extract is non-toxic evident from acute toxicity study.

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Ganoderma applanatum can be a prominent source of CNS depressant, anxiety and pain management.

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Ganoderma applanatum is a bracket fungus with a cosmopolitan distribution.

Applanmerotic acids A and B, two meroterpenoid dimers with an unprecedented polycyclic skeleton from Ganoderma applanatum that inhibit formyl peptide receptor 2

Applanmerotic acids A and B (1 and 2) with a polycyclic skeleton isolated from Ganoderma applantum showed anti-inflammatory activity via inhibiting the activation of FPR2.

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.

Applanaic acids A-C, three new highly oxygenated lanostane triterpenoids from the fruiting bodies of Ganoderma applanatum

Three new highly oxygenated lanostane triterpenoids, applanaic acids A-C (1-3), were isolated from the fruiting bodies of the basidiomycete Ganoderma applanatum. Among them, applanaic acid B (2) possessed the Δ¹⁷⁽²⁰⁾-double bond connection between the side chain and the tetracyclic skeleton, which was not common in the natural lanostane triterpenoids. Their structures were determined by 1D, 2D NMR and HRESIMS spectroscopic analysis. Compound 3 showed a weak acetylcholinesterase (AchE) inhibitory activity with 33.5% inhibition rate at 50 μM.[Figure: see text].

Isolation of benzolactones, Ganodumones A-F from Ganoderma lucidum and their antibacterial activities

Six previously undescribed benzolactone constituents, ganodumones A-F (1-6), a new type of Ganoderma meroterpenoids (GMs) fused with 1,2,3,4,5-pentasubstituted phenyl and 1',2'-dioxy-3'-methyl-pentyl chain were isolated from the fruiting bodies of Ganoderma lucidum. Their structures were determined by spectroscopic analysis, X-ray crystal diffraction, and ECD computational methods. Meanwhile, bioactive evaluation showed that compounds 3 and 5 have antibacterial activities against Microsporum gypseum with MIC₉₀ 56.86 ± 3.98 and 18.48 ± 0.47 μg/mL, respectively.

Fungi: outstanding source of novel chemical scaffolds

A large number of remarkable studies on the secondary metabolites of fungi have been conducted in recent years. This review gives an overview of one hundred and sixty-seven molecules with novel skeletons and their bioactivities that have been reported in seventy-nine articles published from 2013 to 2017. Our statistical data showed that endophytic fungi and marine-derived fungi are the major sources of novel bioactive secondary metabolites.

C28 steroids from the fruiting bodies of Ganoderma resinaceum with potential anti-inflammatory activity

Eight undescribed ergostane-type steroids, (22E,24R)-ergosta-7,22-dien-3β,5α-diol- 6,5-olide, (22E,24R)-ergosta-7,9(11),22-trien-3β,5β,6β-triol, (22E,24R)-6β-methoxy ergosta-7,9(11),22-trien-3β,5α,14β-triol, (22E,24R)-9α,15α-dihydroxyergosta-4,6,8 (14),22-tetraen-3-one, (22E,24R)-ergosta-5,8,22-trien-3β,11α-dihydroxyl-7-one, (22E,24R)-ergosta-4,7,22-trien-3β,9α,14β-trihydroxyl-6-one, (22E,24R)-ergosta-7,22- dien-3β,9α,14β-trihydroxyl-6-one, and (22E,24R)-6β-methoxyergosta-7,22-dien-3β, 5α,9α,14β-tetraol, and twenty-one known analogues were isolated from the fruiting bodies of Ganoderma resinaceum Boud. Their chemical structures were determined on the basis of comprehensive spectroscopic analysis and X-ray crystal diffraction, as well as empirical pyridine-induced deshielding effects. Furthermore, selected compounds were evaluated for their inhibitory effects on macrophage activation using an inhibition of nitric oxide production assay. Finally, (22E,24R)-ergosta-5,8,22- trien-3β,11α-dihydroxyl-7-one, (22E,24R)-ergosta-4,7,22-trien-3β,9α,14β-tri hydroxyl-6-one, (22E,24R)-6β-methoxyergosta-7,22-dien-3β,5α,9α,14β-tetraol, (22E,24R)-ergosta-6,9,22-trien-3β,5α,8α-triol,ergost-6,22-dien-3β,5α,8α-triol, 5α,6α-epoxy-(22E,24R)-ergosta-8,22-diene-3β,7α-diol, 5α,6α-epoxy-(22E,24R)- ergosta-8(14),22-diene-3β,7α-diol, 5α,6α-epoxy-(22E,24R)-ergosta-8(14),22-diene-3β, 7β-diol, and 22E-7α-methoxy-5α,6α-epoxyergosta-8(14),22-dien-3β-ol showed inhibitory effects on NO production with IC₅₀ values ranging from 3.24 ± 0.02 to 35.19 ± 0.41 μM compared with L-NMMA (IC₅₀ 49.86 ± 2.13 μM), indicating that they have potential anti-inflammatory activity.

Aromatic constituents from Ganoderma lucidum and their neuroprotective and anti-inflammatory activities

Five new aromatic compounds, designed as lucidumins A-D (1-4) and lucidimine E (9), along with seven known aromatic compounds (5-8, 10-12) were isolated from Ganoderma lucidum. Their structures were determined by spectroscopic method. Bioactive evaluation showed that compounds 2-4 and 6-10 displayed remarkable neuroprotective activities against corticosterone-induced PC12 cell damage, with the cell viability ranging from 69.99% to 126.00%; and compounds 1-4, 9 and 10 exhibited significant anti-inflammatory activities against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages, with IC₅₀ values ranging from 4.68 to 15.49 μM. In particular, compound 10 showed remarkable neuroprotection with EC₅₀ value of 2.49 ± 0.12 μM, and potent anti-inflammation with IC₅₀ value of 4.68 ± 0.09 μM.

Anti-inflammatory prenylbenzaldehyde derivatives isolated from Eurotium cristatum

Two undescribed prenylbenzaldehyde derivatives, cristaldehydes A and B, and an undescribed quinone derivative, cristaquinone A, along with seven known compounds were isolated from the fungus Eurotium cristatum. The structures of undescribed compounds were determined by spectroscopic analysis including NMR, HR-ESIMS, and single-crystal X-ray diffraction. This is the first report of identification of a dibenzannulated 6,6-spiroketal derivative, cristaldehyde B, in a natural product. Cytotoxic and anti-inflammatory activities of all compounds were evaluated. Cristaldehyde A and cristaquinone A along with five known compounds showed significant anti-inflammatory activities with IC₅₀ values in the range from 0.37 to 14.50 μM.

Benzannulated spiroketal natural products: isolation, biological activity, biosynthesis, and total synthesis

A review discussing the isolation, biological activity, biosynthesis, and total synthesis of naturally occurring benzannulated spiroketals.

Lanostane triterpenoids from Ganoderma luteomarginatum and their cytotoxicity against four human cancer cell lines

Lanostane triterpenoids are major metabolites of macrofungi from the genus Ganoderma and possess enormous substitution diversity and remarkable biological activities, especially anticancer, antioxidant, and anti-inflammatory effects. The present phytochemical investigation resulted in the isolation of nine undescribed lanostane triterpenoids and five known analogues from the fruiting bodies of Ganoderma luteomarginatum, which was first phytochemically studied by our group. Chemical structures were elucidated based on spectroscopic evidence. (5α,23E)-27-nor-lanosta-8,23-dien-3,7,25-trione and (5α,23E)-27-nor-3β-hydroxylanosta-8,23-dien-7,25-dione are undescribed triterpenoids with an unusual 27-nor-lanostane carbon skeleton. All isolates were assayed for their cytotoxic activities using four human cancer cell lines (HGC-27, HeLa, A549, and SMMC-7721) and one human normal cell line (LO2), and the structure-cytotoxicity relationships were preliminarily explored. (5α,24E)-3β-acetoxyl-26-hydroxylanosta-8,24-dien-7-one exhibited the highest cytotoxicity against HeLa and A549 cell lines, with IC₅₀ values of 1.29 and 1.50 μM, respectively.

One new Lignan derivative from the fruiting bodies of Ganoderma lipsiense

One new lignan derivative 2,3-dimethyl-4-(4'-hydroxy-3',5'-dimethoxyphenyl)-6-hydroxy-7-methoxy-naphthalene (1), together with four known analogues (2-5), were isolated from acetone extract of the fruiting bodies of Ganoderma lipsiense collected in the Hainan Province, China. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. Compound 1 showed insecticidal activity against newly hatched karvae of Helicoverpa armigera Hubner. Compounds 1-5 showed moderate antibacterial activity against Staphylococcus aureus with the same MIC value of 1.25 μg/mL.

Meroterpenoids from Ganoderma Species: A Review of Last Five Years

Meroterpenoids are hybrid natural products that partially originate from the terpenoid pathway. Ganoderma meroterpenoids (GMs) are a type of meroterpenoids containing a 1,2,4-trisubstituted phenyl and a polyunsaturated terpenoid part. Over last 5 years, great efforts have been made to conduct phytochemistry research on the genus Ganoderma, which have led to the isolation and identification of a number of GMs. These newly reported GMs showed diverse structures and a wide range of biological activities. This review gives an overview of new GMs from genus Ganoderma and their biological activities and biosynthetic pathway, focusing on the period from 2013 until 2018.

Natural Products Research in China From 2015 to 2016

This review covers the literature published by chemists from China during the 2015-2016 on natural products (NPs), with 1,985 citations referring to 6,944 new compounds isolated from marine or terrestrial microorganisms, plants, and animals. The emphasis is on 730 new compounds with a novel skeleton or/and significant bioactivity, together with their source organism and country of origin.

Recent progress in the isolation, bioactivity, biosynthesis, and total synthesis of natural spiroketals

The isolation, bioactivity, biosynthesis, and total synthesis of natural spiroketals from 2011 to July 2017 have been summarized in this review.

Survey of natural products reported by Asian research groups in 2016

The new natural products reported in peer-reviewed articles in 2016 in journals with good reputations were reviewed and analyzed. The advances that Asian research groups made in the field of natural products chemistry in 2016 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on structural classification.