Planta Med 2011; 77 - SL73
DOI: 10.1055/s-0031-1282196

Structures, absolute configurations and bioogical activities of new unusual metabolites from sponge-associated Aspergillus sp

AH Aly 1, Y Zhou 1, V Wray 2, W Lin 3, B Schulz 4, T Kurtan 5, P Proksch 1
  • 1Institut für Pharmazeutische Biologie und Biotechnologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
  • 2Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
  • 3National Research Laboratories of Natural and Biomimetic Drugs, Peking University, Health Science Center, 38 Xueyuan Road, Haidian District, 100083 Beijing, China
  • 4Institute of Microbiology, Technical University of Braunschweig, Spielmannstrasse 7, 31806 Braunschweig, Germany
  • 5Department of Organic Chemistry, University of Debrecen, PO Box 20, H-4010 Debrecen, Hungary

Over the past years, marine microorganisms have proven to be a prolific source of structurally interesting and biologically active natural products. Marine fungi in particular have attracted considerable interest due to the diversity in chemical structures and biological activities observed for their secondary metabolites.

Chemical investigation of the crude extract obtained from the sponge-associated fungus Aspergillus sp., isolated from a specimen of the Mediterranean sponge Tethya aurantium, yielded new meroterpenoid metabolites of the austalide type, as well as new tryptoquivaline and fumiquinazoline alkaloids, in addition to several known compounds. The structures of the new compounds were unambiguously elucidated on the basis of extensive one- and two-dimensional NMR (1H, 13C, DEPT, COSY, HMQC, HMBC, and ROESY spectra) and mass spectral analysis. The absolute configurations of te new compounds were established by means of TDDFT ECD calculations. All compounds were evaluated for their cytotoxic activity by the MTT method against the murine cancer cell line L5178Y, as well as the human cancer cell lines K562, A2780, and A2780 cisR, where some of the isolated compounds exhibited moderate to pronounced cytotoxicity.

Keywords: Aspergillus, marine fungi, Structure elucidation, absolute configuration, cytotoxicity