Isolation of C-29 oxygenated oleanane triterpenoids and a (+)-muurolene type sesquiterpenoid from the fruiting bodies of Fuscoporia torulosa and their bioactivities

• Published in: Journal of natural medicines 2024-09, Vol.78 (4), p.919-928
• Main Authors: Yoneyama, Tatsuro, Chen, Chian, Ichimura, Yoshihiro, Nakashima, Katsuyuki, Kenmoku, Hiromichi, Imagawa, Hiroshi, Umeyama, Akemi, Noji, Masaaki
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - isolation & purification; Anti-Bacterial Agents - pharmacology; Antifungal agents; Basidiomycota - chemistry; Biomedical and Life Sciences; Biomedicine; Complementary & Alternative Medicine; Crystallography, X-Ray; Drug resistance; Fruit bodies; Fruiting Bodies, Fungal - chemistry; Fuscoporia torulosa; Medicinal Chemistry; Methicillin; Methicillin-Resistant Staphylococcus aureus - drug effects; Microbial Sensitivity Tests; Molecular Structure; Oleanolic Acid - analogs & derivatives; Oleanolic Acid - chemistry; Oleanolic Acid - isolation & purification; Oleanolic Acid - pharmacology; Original Paper; Pharmacology/Toxicology; Pharmacy; Plant Sciences; Secondary metabolites; Sesquiterpenes - chemistry; Sesquiterpenes - isolation & purification; Sesquiterpenes - pharmacology; Stereochemistry; Triterpenes; Triterpenes - chemistry; Triterpenes - isolation & purification; Triterpenes - pharmacology; Triterpenoids
• ISSN: 1340-3443; 1861-0293; 1861-0293
• DOI: 10.1007/s11418-024-01832-z

Basidiomycetes with a wide variety of skeletons of secondary metabolites can be expected to be the source of new interesting biological compounds. During our research on basidiomycetes, two new C-29 oxygenated oleanane-type triterpenes ( 1 and 2 ) and torulosacid ( 3 ), a muurolene type sesquiterpenoid with a five-membered ether ring along with nine known compounds ( 4 – 12 ), were isolated from the MeOH extract of the fruiting bodies of Fuscoporia torulosa . The structures of 1 – 3 were determined by NMR and HREIMS analysis. Further studies on the stereochemistry of 3 were conducted using X-ray crystallographic analysis and comparison of experimental and calculated ECD spectra. In the antimicrobial assay of isolates, 1 , 7 , and 9 showed growth inhibitory activity against methicillin-resistant Staphylococcus aureus and other gram-positive strains. Isolation of oleanane type triterpenes from fungi including basidiomycetes, is a unique report that could lead to further isolation of new compounds and the discovery of unique biosynthetic enzymes. Graphical abstract