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Four new sesterterpenes, arthproliferins A–D (1–4), together with four known derivatives, were isolated and characterized from the mangrove-sediment-derived fungus Arthrinium sp. SCSIO41221. Their structures were determined using detailed nuclear magnetic resonance (NMR) and mass spectroscopic (MS) analyses. Some of the isolated compounds were evaluated for their cytotoxicity in vitro. The results revealed that terpestacin (6) exhibited significant activity with an IC50 value of 20.3 μM, and compounds 2 and 5 were found to show weak inhibitory effects against U87MG-derived GSCs.

Two undescribed cytochalasins, emeriglobosins A (1) and B (2), together with nine previously reported analogues (3–11) and two known tetramic acid derivatives (12, 13) were isolated from the solid culture of Emericellopsis sp. SCSIO41202. Their structures, including the absolute configurations of their stereogenic carbons, were fully elucidated based on spectroscopic analysis and the calculated ECD. Some of the isolated compounds were evaluated for their cytotoxicity and enzyme inhibitory activity against acetylcholinesterase (AChE) in vitro. Among them, 8 showed potent AChE inhibitory activity, with an IC50 value of 1.31 μM, and 5 showed significant cytotoxicity against PC-3 cells, with an IC50 value of 2.32 μM.

Ten polyketide derivatives (1–10), including a new natural product named (E)-2,4-dihydroxy-3-methyl-6-(2-oxopent-3-en-1-yl) benzaldehyde (1), and five known diketopiperazines (11–15), were isolated from the mangrove-sediment-derived fungus Aspergillus sp. SCSIO41407. The structures of 1–15 were determined via NMR and MS spectroscopic analysis. In a variety of bioactivity screening, 3 showed weak cytotoxicity against the A549 cell line, and 2 exhibited weak antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Compounds 3, 5, and 6 showed inhibition against acetylcholinesterase (AChE) with IC50 values of 23.9, 39.9, and 18.6 μM. Compounds 11, 12, and 14 exhibited obvious inhibitory activities of lipopolysaccharide (LPS)-induced nuclear factor-κB (NF-κB) with IC50 values of 19.2, 20.9, and 8.7 μM, and they also suppressed RANKL-induced osteoclast differentiation in bone marrow macrophages cells (BMMCs), with the concentration of 5 μM. In silico molecular docking with AChE and NF-κB p65 protein were also performed to understand the inhibitory activities, and 1, 11–14 showed obvious protein/ligand-binding effects to the NF-κB p65 protein.

Four new compounds, including two new polyketides, heterocornols M and N (1, 2), and a pair of epimers, heterocornols O and P (3, 4), were isolated from the fermentation broth of the marine sponge-derived fungus Pestalotiopsis heterocornis XWS03F09, together with three known compounds (5−7). The new chemical structures were established on the basis of a spectroscopic analysis, optical rotation, experimental and calculated electronic circular dichroism (ECD). All of the compounds (1−7) were evaluated for their cytotoxic activities, and heterocornols M-P (1−4) exhibited cytotoxicities against four human cancer cell lines with IC50 values of 20.4−94.2 μM.

A new macrodiolide, mangrovlide A (1) and two new polycyclic chromones, penixanthones C (2) and D (3), as well as four other known compounds (4−7), have been isolated from the mangrove sediment derived fungus Penicillium sp. SCSIO041218, cultured in the 0.25% NaCl rice substrate. The structures of the new compounds were determined by analysis of the NMR and MS spectroscopic data. Compound 1 possesses a 10-membered macrodiolide unit, while 2 and 3 are chromones with an unprecedented 6/6/6/5 polycyclic skeleton. Compounds 1−7 were evaluated for their cytotoxicities, while all the compounds displayed weak or no activity.

Two new alkaloids, fumigatosides E (1) and F (2), and a new natural product, 3, 7-diketo-cephalosporin P1 (6) along with five known compounds (3–5, 7, 8) were isolated from deep-sea derived fungal Aspergillus fumigatus SCSIO 41012. Their structures were determined by extensive spectroscopic data analysis, including 1D, 2D nuclear magnetic resonance (NMR) and mass spectrometry (MS), and comparison between the calculated and experimental electronic circular dichroism (ECD) spectra. In addition, all compounds were tested for antibacterial and antifungal inhibitory activities. Compound 1 showed significant antifungal activity against Fusarium oxysporum f. sp. momordicae with MIC at 1.56 µg/mL. Compound 4 exhibited significant higher activity against S. aureus (16,339 and 29,213) with MIC values of 1.56 and 0.78 µg/mL, respectively, and compound 2 exhibited significant activity against A. baumanii ATCC 19606 with a MIC value of 6.25 µg/mL.

Chemical investigation of the fungus Penicillium sp. SCSIO Ind16F01 derived from deep-sea sediment sample afforded a new xanthone, 3,8-dihydroxy-2-methyl-9-oxoxanthene-4-carboxylic acid methyl ester (1) and a new chromone, coniochaetone J (2), together with three known xanthones, 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ester (3), 7,8-dihydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ester (4), 1,6,8-trihydroxy-3-(hydroxymethyl)anthraquinone (5), three known chromones, coniochaetone B (6), citrinolactones B (7), epiremisporine B (8), and four reported rare class of N-methyl quinolone lactams: quinolactacins B (9), C1 (10), and C2 (11), and quinolonimide (12). The structures of new compounds were determined by analysis of the NMR and MS spectroscopic data. Those isolated compounds were evaluated for their antiviral (EV71 and H3N2) and cytotoxic activities.

Bis-naphtho-γ-pyrones (BNPs) are an important group of aromatic polyketides derived from fungi, and asperpyrone-type BNPs are produced primarily by Aspergillus species. The fungal strain Aspergillus niger SCSIO Jcsw6F30, isolated from a marine alga, Sargassum sp., and identified according to its morphological traits and the internal transcribed spacer (ITS) region sequence, was studied for BNPs secondary metabolisms. After HPLC/MS analysis of crude extract of the fermentation broth, 11 asperpyrone-type BNPs were obtained directly and quickly by chromatographic separation in the extract, and those isolated asperpyrone-type BNPs were structurally identified by NMR and MS analyses. All of the BNPs showed weak cytotoxicities against 10 human tumor cells (IC50 > 30 μM). However, three of them, aurasperone F (3), aurasperone C (6) and asperpyrone A (8), exhibited obvious COX-2–inhibitory activities, with the IC50 values being 11.1, 4.2, and 6.4 μM, respectively. This is the first time the COX-2–inhibitory activities of BNPs have been reported.

Two new alkaloids, fumigatosides E (1) and F (2), and a new natural product, 3, 7-diketo-cephalosporin P1 (6) along with five known compounds (3-5, 7, 8) were isolated from deep-sea derived fungal Aspergillus fumigatus SCSIO 41012. Their structures were determined by extensive spectroscopic data analysis, including 1D, 2D nuclear magnetic resonance (NMR) and mass spectrometry (MS), and comparison between the calculated and experimental electronic circular dichroism (ECD) spectra. In addition, all compounds were tested for antibacterial and antifungal inhibitory activities. Compound 1 showed significant antifungal activity against Fusarium oxysporum f. sp. momordicae with MIC at 1.56 µg/mL. Compound 4 exhibited significant higher activity against S. aureus (16,339 and 29,213) with MIC values of 1.56 and 0.78 µg/mL, respectively, and compound 2 exhibited significant activity against A. baumanii ATCC 19606 with a MIC value of 6.25 µg/mL. [ABSTRACT FROM AUTHOR]