Bioactive polyketides from a marine green alga-derived fungus Aspergillus sp. NTU967

In the preliminary screening, the bioactivities of 343 fungal strains isolated from marinemacroalgae collected from northeast coast of Taiwan were evaluated intensively. Of these, the ethyl acetate extract of the fermented broth of Aspergillus sp. NTU967 was found to exhibit significant antimicrobial activity against Staphylococcus aureus ATCC29213.

To disclose the active principles from the ethyl acetate extract of the fermented broth of Aspergillus sp. NTU967.

Eleven compounds including seven new compounds, namely aspergilsmins A–G (1–7), were identified by spectroscopic analysis. Among these, aspergilsmins E (5) and F (6) exhibited significant growth inhibition against S. aureus ATCC29213 with MIC values of 32 μg/mL. Aspergilsmin C (3) showed potent cytotoxicity against PC-3 prostate cancer cells and SK-Hep-1 hepatocellular carcinoma cells with IC₅₀ values of 7.3 ± 0.2 and 2.7 ± 0.2 μM, respectively. Additionally, 3 also exhibited potent antiangiogenic activity by suppressing the tube formation of human endothelial progenitor cells with an IC₅₀ of 4.6 ± 0.3 μM.

leven chemical entities including seven new compounds were isolated from an alga-derived fungus Aspergillus sp. NTU967. Of these, compounds 3, 5, and 6 were the new compounds with bioactivities.

Fig. 1

• References

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