Neogrisphenol A, a Potential Ovarian Cancer Inhibitor from a New Record Fungus Neohelicosporium griseum

Novel drimane-type sesquiterpenoids and nucleosides from the Helicoma septoconstrictum suppress the growth of ovarian cancer cells

Four new drimane-type sesquiterpenoids and two new nucleoside derivatives (1-6), were isolated from the fungus Helicoma septoconstrictum. Their structures were determined based on the combination of the analysis of their HR-ESI-MS, NMR, ECD calculations data and acid hydrolysis. All the isolated compounds were detected for their bio-activities against MDA-MB-231, A549/DDP, A2780 and HepG2 cell lines. Helicoside C (4) exhibited superior cytotoxicity against the A2780 cell line with IC50 7.5 ± 1.5 µM. The analysis of reactive oxygen species (ROS) revealed that Helicoside C induced an increase in intracellular ROS. Furthermore, the flow cytometry and mitochondrial membrane potential (MMP) analyses unveiled that Helicoside C mediated mitochondrial-dependent apoptosis in A2780 cells. The western blotting test showed that Helicoside C could suppress the STAT3's phosphorylation. These findings offered crucial support for development of H. septoconstrictum and highlighted the potential application of drimane-type sesquiterpenoids in pharmaceuticals.

A New Brominated Isocoumarin from the Marine Starfish-Associated Fungus Aspergillus sp. WXF1904

Based on the one strain many compounds strategy, a new brominated isocoumarin, 5-bromo-6,8-dihydroxy-3,7-dimethylisocoumarin (1), along with four new natural products, methyl 3-bromo-2,4-dihydroxy-6-methylbenzoate (2), methyl 2-bromo-4,6-dihydroxybenzoate (3), (E)-3-(3-bromo-4-hydroxyphenyl) acrylic acid (4) and 4-hydroxy-3-methyl-6-phenyl-2H-pyran-2-one (5), and four known compounds, methyl orsellinate (6), 4-hydroxy-3-methyl-6-(1-methyl-1-propenyl)-2H-pyran-2-one (7), pilobolusate (8) and cis-ferulic acid (9), were isolated from the ethyl acetate extract of the fungus Aspergillus sp. WXF1904 under the condition of adding bromine salt to the production medium. The structures of the new compounds were established by analysis of NMR and MS data. Compounds (1-9) were evaluated for inhibitory activity of acetylcholinesterase and pancreatic lipase, the new compound 1, known compounds 6 and 7 displayed weak inhibitory activity against acetylcholinesterase, compounds 2, 5, 7 and 8 showed weak inhibitory activity against pancreatic lipase.

Isolation and Structure Elucidation of New Metabolites from the Mariana-Trench-Associated Fungus Aspergillus sp. SY2601

Fungi are important resource for the discovery of novel bioactive natural products. This study investigated the metabolites produced by Mariana-Trench-associated fungus Aspergillus sp. SY2601 in EY liquid and rice solid media, resulting in the isolation and structure determination of 28 metabolites, including five new compounds, asperindopiperazines A-C (1-3), 5-methoxy-8,9-dihydroxy-8,9-deoxyaspyrone (21), and 12S-aspertetranone D (26). Structures of the new compounds were elucidated based on extensive NMR spectral analyses, HRESIMS data, optical rotation, ECD, and 13C NMR calculations. The new compound 12S-aspertetranone D (26) exhibited antibacterial activity against both methicillin-resistant Staphylococcus aureus and Escherichia coli with MIC values of 3.75 and 5 μg/mL, respectively.

Additions to the Genus Helicosporium (Tubeufiaceae, Tubeufiales) from China with an Identification Key for Helicosporium Taxa

Helicosporous hyphomycetes is a group of filamentous fungi that shows promising application prospects in metabolizing bioactive natural compounds. During a study of helicosporous fungi in China, six new helicosporous taxa were collected and isolated from decaying wood in Guangxi Zhuang Autonomous Region, China. Morphological comparisons with multi-gene phylogenetic analyses revealed that these six taxa belong to Helicosporium (Tubeufiaceae, Tubeufiales), and they were recognized as three novel species and were named Helicosporium liuzhouense, H. multidentatum, and H. nanningense. Detailed descriptions and illustrations of the newly discovered taxa and comparisons with similar fungi are provided. In addition, a list and a key to accepted Helicosporium species are provided.