Abstract

The fungus Aspergillus amoenus Roberg strain UP197 was shown to produce antibacterial tetramic acid based alkaloids. Two new compounds, pyranterreone I and J (1 and 2), were isolated and characterized, in addition to the known compounds cordylactam, 7-hydroxycordylactam, pyranterreone C, D, F and G. Neither the pyranterreones nor the cordylacctams had previously been tested for antimicrobial activity. Thus, all isolated compounds were tested against a panel of clinically important bacteria and fungi. Pyranterreone C was active against Gram-positive and Gram-negative bacteria, with minimal inhibitory concentrations (MIC) between 1 and 8 mu g/mL, whereas the MICs for all other compounds were >32 mu g/mL. Pyranoterreone C was cytotoxic towards HepG2 cells, and since pyranterreone C reacted rapidly with the nucleophile cysteine, it is likely that the observed antibacterial activity is due to the chemical reactivity rather than enzymatic affinity, making it unsuitable for development as an antibacterial drug.

Keywords

Aspergillus amoenus; alkaloids; pyranterreone; antibacterial; cytotoxic

Published in

Natural Product Research
2022, Volume: 36, number: 4, pages: 967-973
Publisher: TAYLOR AND FRANCIS LTD

SLU Authors

• Nord, Christina

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

• Levenfors, Jolanta

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

• Bjerketorp, Joakim

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

• Guss, Bengt

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Broberg, Henrik

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Medicinal Chemistry


Publication identifier

DOI: https://doi.org/10.1080/14786419.2020.1855643

Permanent link to this page (URI)

https://res.slu.se/id/publ/110481