Two new metabolites, diorcinolic acid (1) and β-d-glucopyranosyl aspergillusene A (8), together with six diphenylethers (2-7), a diketopiperazine (9), a chromone (10) and a xanthone (11) were isolated from the fungus Aspergillus sydowii derived from the marine sponge Stelletta sp. The planar structures and their relative configurations were elucidated by analysing 1D, 2D NMR and HRESIMS data. Compound 8 is the first glycoside of phenolic bisabolane sesquiterpenes. Compounds 1 and 8 exhibited mild cytotoxicity against KB (human nasopharyngeal carcinoma cells), HepG2 (human liver cancer cells) and HCT 116 (human colon cancer cells). All compounds were evaluated for antibacterial activity and their abilities to suppress LPS-induced nitric oxide (NO) production. Compounds 2 and 4-7 showed mild antibacterial activity against human pathogen Staphylococcus aureus and fish pathogens Streptococcus iniae and Vibrio ichthyoenteri, and compounds 4 and 7 weakly suppressed NO production.

Two new cyclic peptides, pentaminomycins A (1) and B (2), were isolated from cultures of Streptomyces sp. RK88-1441. Based on the interpretation of the NMR, UV, IR, and MS data, the planar structures of 1 and 2 were elucidated as cyclic pentapeptides with a modified amino acid residue, N-hydroxyarginine (N5-OH-Arg). The absolute configurations of the constituent amino acid residues were determined by the advanced Marfey's method. Localization of l- and d-amino acids in the sequence was ascertained by chiral analysis of the fragment peptide obtained from a partial hydrolysate; amino acids were identified by LC-MS. Pentaminomycin A (1) reduced α-MSH-stimulated melanin synthesis by suppressing the expression of melanogenic enzymes including tyrosinase, tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2).

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Four new compounds, phomalichenones A-D (1-4), and seven known compounds (5-11) were isolated from the cultures of an endolichenic fungus Phoma sp. EL002650. Their structures were determined by the analysis of their spectroscopic data (NMR and MS). Compounds 1 and 6 inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. In addition, compound 1 diminished the protein expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and decreased the mRNA expression levels of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin(IL)-1β, and IL-6.