Eleven new ophiobolin-type sesterterpenoids, asperophiobolins A−K (1−11), along with 12 known analogues (12−23) were isolated from the cultures of the mangrove endophytic fungus Aspergillus sp. ZJ-68. The structures of the new compounds were elucidated through spectroscopic analyses, and their absolute configurations were assigned by a combination of Mo 2 (AcO) 4 -induced electronic circular dichroism spectra and quantum chemical calculations. Asperophiobolins A−D (1−4) represent the first examples possessing a five-membered lactam unit between C-5 and C-21 in ophiobolin derivatives. In the bioactivity assays, compounds 8−10 and 14−17 exhibited inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophage cells with IC 50 values ranging from 9.6 to 25 μM, and compound 8 was found to show comparable inhibition of Mycobacterium tuberculosis protein tyrosine phosphatase B with an IC 50 value of 19 μM.

Six new polyketides, including one coumarin (1), two isocoumarins (2 and 3), dihydroradicinin (4), and two benzofuranone derivatives (7 and 8), together with seven known analogues (5–6 and 9–13) were isolated from the culture of the mangrove endophytic fungus Epicoccum nigrum SCNU-F0002. The structures were elucidated on the interpretation of spectroscopic data. The absolute configuration of Compounds 2 and 3 were determined by comparison of their ECD spectra with the data of their analogue dihydroisocoumarins described in the literature. The absolute configuration of 4 was determined by single-crystal X-ray diffraction. All the compounds were screened for their antioxidant, antibacterial, anti-phytopathogenic fungi and cytotoxic activities. Using a DPPH radical-scavenging assay, Compounds 10–13 showed potent antioxidant activity with IC50 values of 13.6, 12.1, 18.1, and 11.7 μg/mL, respectively. In addition, Compounds 6 and 7 showed antibacterial effects against Bacillus subtilis (ATCC 6538), Escherichia coli (ATCC 8739), and Staphylococcus aureus (ATCC 6538), with MIC values in the range of 25–50 μg/mL.

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Two new compounds, an abscisic acid-type sesquiterpene (1), and one asterric acid derivative (2), together with three known compounds (3-5) were isolation from mangrove endophytic fungus Pleosporales sp. SK7. The structures of these metabolites were determined by NMR, X-ray crystal diffraction, CD and HR-ESI-MS. All compounds were tested for their antibacterial, antioxidant and cytotoxic activities, among these compounds, 5 showed cytotoxicity against MDA-MB-435 cell with an IC 50 of 25.96±0.32 μM.

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