Xiaochu Qin

Antiviral Merosesquiterpenoids Produced by the Antarctic Fungus Aspergillus ochraceopetaliformis SCSIO 05702

Five new highly oxygenated α-pyrone merosesquiterpenoids, ochraceopones A-E (1-5), together with one new double bond isomer of asteltoxin, isoasteltoxin (6), and two known asteltoxin derivatives, asteltoxin (7) and asteltoxin B (8), were isolated from an Antarctic soil-derived fungus, Aspergillus ochraceopetaliformis SCSIO 05702. Their structures were determined through extensive spectroscopic analysis, CD spectra, quantum mechanical calculations, and X-ray single-crystal diffraction. Ochraceopones A-D (1-4) are the first examples of α-pyrone merosesquiterpenoids possessing a linear tetracyclic carbon skeleton, which has not been previously described. All the isolated compounds were tested for their antiviral, cytotoxic, antibacterial, and antitubercular activities. Among these compounds, ochraceopone A (1), isoasteltoxin (6), and asteltoxin (7) exhibited antiviral activities against the H1N1 and H3N2 influenza viruses with IC50 values of >20.0/12.2 ± 4.10, 0.23 ± 0.05/0.66 ± 0.09, and 0.54 ± 0.06/0.84 ± 0.02 μM, respectively. A possible biosynthetic pathway for ochraceopones A-E (1-5) was proposed.

Arthpyrones A–C, Pyridone Alkaloids from a Sponge-Derived Fungus Arthrinium arundinis ZSDS1-F3

Three new 4-hydroxy-2-pyridone alkaloids, arthpyrones A-C (1-3), were isolated from the sponge-derived fungus Arthrinium arundinis ZSDS1-F3. Their structures were elucidated on the basis of spectroscopic analysis, CD spectra, quantum chemical calculation, and X-ray single-crystal diffraction analysis. Compounds 1 and 2 possessed a 2-pyridone core featured with a decalin moiety linked via a carboxide bridge bearing a novel oxabicyclo[3.3.1]nonane ring system rarely discovered in nature. A possible biosynthetic pathway for them was proposed.

Sydoxanthone C and acremolin B produced by deep-sea-derived fungus Aspergillus sp. SCSIO Ind09F01

A new xanthone named sydoxanthone C (1) and a new alkaloid named acremolin B (2), together with 10 known compounds (3–12) were isolated from a deep-sea-derived fungus Aspergillus sp. SCSIO Ind09F01. The structures of compounds (1–12) were determined by the extensive 1D, 2D-NMR, High resolution mass spectra (HRESIMS) data. Compounds 7, 8, 11 and 12 showed significant selective cytotoxicities against HeLa, DU145 and U937 cell lines. In addition, compounds 7, 8 and 11 also exhibited COX-2 inhibitory activities with the prominent IC50 values of 2.4, 7.1 and 10.6 μM, respectively.

Three new indolyl diketopiperazine metabolites from the antarctic soil-derived fungus Penicillium sp. SCSIO 05705

Three new indolyl diketopiperazine derivatives, penillines A and B (1 and 3), isopenilline A (2), together with seven known alkaloid compounds (E)-3-(1H-imidazole-4-yimethylene)-6-(1H-indl-3-ylmethyl)-2,5-piperazinediol (4), penilloid A (5), meleagrin (6), neoxaline (7), questiomycin A (8), N-(2-hydroxyphenyl)-acetamide (9), 2-benzoxazolinone (10), were isolated from the Antarctic soil-derived fungus Penicillium sp. SCSIO 05705. The new structures of 1–3 were elucidated on the basis of 1D and 2D NMR, mass spectra, CD spectra, and quantum chemical calculations. All the isolated compounds were tested for their antiviral (H1N1 and H3N2), antituberculosis, antibacterial, and cytotoxic activities. Among them, compounds 6–8 had significant in vitro cytotoxicities against the K562, MCF-7, A549, U937, Hela, DU145, HL60, and HT29 cell lines, with IC50 values ranging from 2.73 to 17.7 μM. In addition, compound 8 showed potent antituberculosis activity with an MIC value of 3.91 μM, and the inhibition effect was close to the positive control INH (isoniazid, MIC 2.04 μM). A possible biogenesis pathway for compounds 1–7 was proposed.

Asteltoxins with Antiviral Activities from the Marine Sponge-Derived Fungus Aspergillus sp. SCSIO XWS02F40

Two new asteltoxins named asteltoxin E (2) and F (3), and a new chromone (4), together with four known compounds were isolated from a marine sponge–derived fungus, Aspergillus sp. SCSIO XWS02F40. The structures of the compounds (1–7) were determined by the extensive 1D- and 2D-NMR spectra, and HRESIMS spectrometry. All the compounds were tested for their antiviral (H1N1 and H3N2) activity. Compounds 2 and 3 showed significant activity against H3N2 with the prominent IC50 values of 6.2 ± 0.08 and 8.9 ± 0.3 μM, respectively. In addition, compound 2 also exhibited inhibitory activity against H1N1 with an IC50 value of 3.5 ± 1.3 μM.

Antituberculosis compounds from a deep-sea-derived fungus Aspergillus sp. SCSIO Ind09F01

Abstract Eleven diketopiperazine and fumiquinazoline alkaloids (1–11) together with a tetracyclic triterpenoid helvolic acid (12) were obtained from the cultures of a deep-sea derived fungus Aspergillus sp. SCSIO Ind09F01. The structures of these compounds (1–12) were determined mainly by the extensive NMR, ESIMS spectra data and by comparison with previously described compounds. Besides, anti-tuberculosis, cytotoxic, antibacterial, COX-2 inhibitory and antiviral activities of these compounds were evaluated. Gliotoxin (3), 12,13-dihydroxy-fumitremorgin C (11) and helvolic acid (12) exhibited very strong anti-tuberculosis activity towards Mycobacterium tuberculosis with the prominent MIC50 values of <0.03, 2.41 and 0.894 μM, respectively, which was here reported for the first time. Meanwhile gliotoxin also displayed significant selective cytotoxicities against K562, A549 and Huh-7 cell lines with the IC50 values of 0.191, 0.015 and 95.4 μM, respectively.

Tetramic acid derivatives and polyphenols from sponge-derived fungus and their biological evaluation

Fifteen compounds, including two tetramic acid derivatives, penicillenol A1 (1) and penicillenol A2 (2), six polyphenols containing both phenolic bisabolane sesquiterpenoid and diphenyl ether units, expansols A–F (3–8), together with six phenolic bisabolane sesquiterpenoids (9–14) and diorcinol (15), were isolated from the fermentation broth of the marine-derived fungus ZSDS1-F11 isolated from the sponge Phakellia fusca Thiele collected in the Yongxing island of Xisha. Their structures were elucidated mainly by using extensive NMR spectroscopic and mass spectrometric analyses. Compounds 3–5, 7 and 8 showed potent COX-1 inhibitory activity with IC50 values of 5.3, 16.2, 30.2, 41.0 and 56.8 μM, respectively. Meanwhile, compounds 3–8 showed potent COX-2 inhibitory activity with IC50 values of 3.1, 5.6, 3.0, 5.1, 3.2 and 3.7 μM, respectively. In addition, compound 1 exhibited antituberculosis activity with 96.1% inhibition at concentration of 10 μM.

Quinone/hydroquinone meroterpenoids with antitubercular and cytotoxic activities produced by the sponge-derived fungus Gliomastix sp. ZSDS1-F7

Abstract Fifteen compounds, including six quinone/hydroquinone meroterpenoids, purpurogemutantin (1), macrophorin A (2), 4′-oxomacrophorin (3), 7-deacetoxyyanuthone A (4), 2,3-hydro-deacetoxyyanuthone A (5), 22-deacetylyanuthone A (6), anicequol (7), three roquefortine derivatives, roquefortine C (8), (16S)-hydroxyroquefortine C (9), (16R)-hydroxyroquefortine C (10), dihydroresorcylide (11), nectriapyrone (12), together with three fatty acid derivatives, methyl linoleate (13), phospholipase A2 (14), methyl elaidate (15), were isolated from the sponge-derived fungus Gliomastix sp. ZSDS1-F7 isolated from the sponge Phakellia fusca Thiele collected in the Yongxing island of Xisha. Their structures were elucidated mainly by extensive NMR spectroscopic and mass spectrometric analyses. Among these compounds, compounds 1–3 and 5–7 showed significant in vitro cytotoxicities against the K562, MCF-7, Hela, DU145, U937, H1975, SGC-7901, A549, MOLT-4 and HL60 cell lines, with IC50 values ranging from 0.19 to 35.4 μM. And compounds 2–4 exhibited antitubercular activity with IC50 values of 22.1, 2.44 and 17.5 μM, respectively. Furthermore, compound 7 had anti-enterovirus 71 activity with MIC value of 17.8 μM. To the best of our knowledge, this is the first report to product two quinone/hydroquinone meroterpenoids skeletons (linear skeleton and drimane skeleton) from the same fungal strain.

New phenyl derivatives from endophytic fungus Botryosphaeria sp. SCSIO KcF6 derived of mangrove plant Kandelia candel

Two new phenyl derivatives (1 and 3), along with two new natural products (4 and 5), and three known compounds (2, 6 and 7), were isolated from an endophytic fungus Botryosphaeria sp. SCSIO KcF6. The structures of these compounds 1–7 were elucidated by the extensive 1D and 2D-NMR and HRESIMS Data analysis, and compared with those of reported data. The absolute configuration of the compounds 1 and 3 were assigned by optical rotation and CD data. The isolated compounds were evaluated for their cytotoxic, anti-inflammatory (COX-2) and antimicrobial activities. Compound 3 exhibited a specific COX-2 inhibitory activity with the IC50 value of 1.12 μM.

Aspergone, a new chromanone derivative from fungus Aspergillus sp. SCSIO41002 derived of mangrove soil sample

Aspergone, a new chromanone derivative from fungus Aspergillus sp. SCSIO41002 derived of mangrove soil sample