title: Bioactive metabolites from the endophytic fungus Ampelomyces sp. isolated from the medicinal plant Urospermum picroides.
abstract: Extracts of cultures grown in liquid or on solid rice media of the fungal endophyte Ampelomyces sp. isolated from the medicinal plant Urospermum picroides exhibited considerable cytotoxic activity when tested in vitro against L5178Y cells. Chromatographic separation yielded 14 natural products that were unequivocally identified based on their 1H and 13C NMR as well as mass spectra and comparison with previously published data. Six compounds (2, 4, 5, 7, 9 and 11) were natural products. Both fungal extracts differed considerably in their secondary metabolites. The extract obtained from liquid cultures afforded a pyrone (2) and sulfated anthraquinones (7 and 9) along with the known compounds 1, 3, 6 and 8. When grown on solid rice medium the fungus yielded three compounds 4, 5 and 11 in addition to several known metabolites including 6, 8, 10, 12, 13 and 14. Compounds 4, 8 and 10 showed the strongest cytotoxic activity against L5178Y cells with EC50 values ranging from 0.2-7.3microg/ml. Furthermore, 8 and 10 displayed antimicrobial activity against the Gram-positive pathogens, Staphylococcus aureus, S. epidermidis and Enterococcus faecalis at minimal inhibitory concentrations (MIC) of 12.5microg/ml and 12.5-25microg/ml, respectively. Interestingly, 6 and 8 were also identified as constituents of an extract derived from a healthy plant sample of the host plant U. picroides thereby indicating that the production of bioactive natural products by the endophyte proceeds also under in situ conditions within the host plant.
authors.affiliation: Institut für Pharmazeutische Biologie und Biotechnologie, Heinrich-Heine-Universität, Universitätsstrasse 1, Geb. 26.23, D-40225 Düsseldorf, Germany.
authors.forename: Amal H
authors.initials: AH
authors.lastname: Aly
authors.forename: Ruangelie
authors.initials: R
authors.lastname: Edrada-Ebel
authors.forename: Victor
authors.initials: V
authors.lastname: Wray
authors.forename: Werner E G
authors.initials: WE
authors.lastname: Müller
authors.forename: Svitlana
authors.initials: S
authors.lastname: Kozytska
authors.forename: Ute
authors.initials: U
authors.lastname: Hentschel
authors.forename: Peter
authors.initials: P
authors.lastname: Proksch
authors.forename: Rainer
authors.initials: R
authors.lastname: Ebel
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001203:Ascomycota / Q000737:chemistry* / Q000254:growth & development / Q000378:metabolism; D019659:Asteraceae / Q000382:microbiology*; D001419:Bacteria / Q000187:drug effects; D045744:Cell Line, Tumor; D003603:Cytotoxins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D008401:Gas Chromatography-Mass Spectrometry; D007940:Leukemia L5178 / Q000188:drug therapy*; D051379:Mice; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000382:microbiology*
chemical_list: D000890:Anti-Infective Agents; D003603:Cytotoxins