Secondary Metabolites with Nitric Oxide Inhibition from Marine-Derived Fungus Alternaria sp. 5102.

Two new benzofurans, alternabenzofurans A and B (1 and 2) and two new sesquiterpenoids, alternaterpenoids A and B (3 and 4), along with 18 known polyketides (5-22), were isolated from the marine-derived fungus Alternaria sp. 5102. Their structures were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-ESIMS, and ECD) and X-ray crystallography, as well as the modified Mosher's method. Compounds 2, 3, 5, 7, 9-18, and 20-22 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide with IC50 values in the range from 1.3 to 41.1 µM. Structure-activity relationships of the secondary metabolites were discussed.

Anti-inflammatory Mono- and Dimeric Sorbicillinoids from the Marine-Derived Fungus Trichoderma reesei 4670.

Eight new dimeric sorbicillinoids (1-3, 5-9) and 12 new monomeric sorbicillinoids (10-20, 25), along with five known analogues (4 and 21-24), were isolated from the marine-derived fungus Trichoderma reesei 4670. Their structures were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-ESIMS, and ECD) and X-ray crystallography. Compound 1, containing a pyrrolidin-2-one moiety, is reported for the first time in the sorbicillinoid family. Compounds 8 and 9 are the first examples of bisorbicillinoids possessing a benzofuro[2,3- h]chromene scaffold from a natural source. Compounds 3-11, 13-16, 18, 21, 22, 24, and 25 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide with IC50 values in the range from 0.94 to 38 µM. Structure-activity relationships of the sorbicillinoids were discussed.

Roussoelins A and B: two phenols with antioxidant capacity from ascidian-derived fungus Roussoella siamensis SYSU-MS4723.

Ascidian-derived microorganisms are a significant source of pharmacologically active metabolites with interesting structural properties. When discovering bioactive molecules from ascidian-derived fungi, two new phenols, roussoelins A (1) and B (2), and ten known polyketides (3-12) were isolated from the ascidian-derived fungus Roussoella siamensis SYSU-MS4723. The planar structure of compounds 1 and 2 was established by analysis of HR-ESIMS and NMR data. The conformational analysis of the new compounds was assigned according to coupling constants and selective gradient NOESY experiments, and absolute configurations were completed by the modified Mosher's method. Among the isolated compounds, 1, 2, and 9 showed moderate antioxidant capacity.

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.

Bioactive terpenoids from Santalum album derived endophytic fungus Fusarium sp. YD-2.

Two new spiromeroterpenoids, namely fusariumin A (1) and B (2), along with four known terpenoids, asperterpenoid A (3), agathic acid (4), guignardone N (5), and trametenolic acid (6), were obtained from the endophytic fungus Fusarium sp. YD-2, derived from the twigs of Santalum album. Their structures were elucidated by a combination of spectroscopic analyses. The absolute configuration of 1 was determined by single-crystal X-ray diffraction using Cu Kα radiation, and that of 2 was elucidated on the basis of experimental and calculated electronic circular dichroism spectra. Compound 2 exhibited moderate anti-inflammatory activity in vitro by inhibiting nitric oxide (NO) production in lipopolysaccharide activated RAW264.7 cells with an IC50 value of 50 µM, and compound 3 showed strong anti-inflammatory activity with an IC50 value of 1.6 µM. In the antibacterial assay, compound 1 displayed significant activities against Staphylococcus aureus and Pseudomonas aeruginosa with an MIC value of 6.3 µg mL-1, and compound 3 showed moderate activities against Salmonella enteritidis and Micrococcus luteus with MIC values of 6.3 and 25.2 µg mL-1, respectively.