Six new metabolites produced by <i>Colletotrichum</i><i>aotearoa</i> 09F0161, an endophytic fungus isolated from <i>Bredia</i><i>oldhamii</i>

<div><p>Six new compounds, colletobredins A–D (<b>1</b>–<b>4</b>) and colletomelleins A and B (<b>5</b> and <b>6</b>), along with 12 previously identified compounds, were isolated from the culture broth of <i>Colletotrichum aotearoa</i> BCRC 09F0161, a fungal endophyte residing in the leaves of an endemic Formosan plant <i>Bredia oldhamii</i> Hook. f. (Melastomataceae). The structures of the new compounds were established by spectroscopic methods, including UV, IR, HR-ESIMS and extensive 1D and 2D NMR techniques. The effects of some isolates on the inhibition of nitric oxide (NO) production in lipopolysaccharide-activated murine macrophage RAW264.7 cells were evaluated. All these compounds inhibited NO production in activated macrophages without any cytotoxicity at a concentration of 100 μM. Of these isolates, <b>1</b> showed weak NO inhibitory activity with IC₅₀ value of 182.2 μM. To the best of our knowledge, this is the first report on isochroman glycoside metabolites (<b>1</b>–<b>4</b>) from the genus <i>Colletotrichum</i>.</p>