Diaporphasines E and F: New Polyketides from the Saprotrophic Fungus Lachnum sp. IW157 Growing on the Reed Grass Phragmites communis .

Chemical investigation for the mycelial extract of a saprotrophic fungus Lachnum sp. IW157 growing on the common reed grass Phragmites communis afforded the identification of two polyketide metabolites diaporphasines E ( 1 ) and F ( 2 ). Chemical structures of isolated compounds were unambiguously elucidated based on extensive 1D and 2D NMR spectral analyses in addition to their high-resolution mass spectrometry. The isolated compounds were assessed for their cytotoxicity and antimicrobial and biofilm inhibitory activities. While compound 1 revealed potent cytotoxicity against the tested cell lines L929 and KB3.1 with IC 50 values of 0.9 and 3.7 μM, respectively, compound 2 exhibited moderate effects on the formation of S. aureus biofilms at 31.25 μg/mL.