Isolation, structural elucidation, and biological activity of a novel isocoumarin from the dark septate endophytic fungus Phialocephala fortinii .

A novel isocoumarin was isolated from the mycelia of the dark septate endophytic fungus Phialocephala fortinii . The chemical structure was determined to be 8-hydroxy-6-methoxy-3,7-dimethyl-1 H -2-benzopyran-1-one based on mass spectrometry, 1 H-nuclear magnetic resonance (NMR), and 13 C-NMR spectroscopic analyses, including 2D-NMR experiments. The isolated compound inhibited root growth of Arabidopsis thaliana , suggesting its potential as a plant growth regulator.