Bioactive secondary metabolites from Talaromyces rugulosus GIZ45-A37 and their anti-inflammatory activity

As part of our plan to discover new bioactive ingredients from entomophagous fungi, a new macrolide compound, talarolide (1), and a new bioactive natural product, talarenal (2), with two known compounds, WF-3681 methy ester (3) and aspergillumarin A (4) were isolated from an insect derived strain Talaromyces rugulosus GIZ45-A37. The structures were determined based on extensive comprehensive spectroscopic (NMR and HR-ESI-MS) analyses and compared with literature values. The relative configuration of 1 was defined by DFT-NMR chemical shift calculations and subsequent DP4/DP4+ probability methods. Compounds 1 and 2 showed inhibitory effect on IL-6 production at 10 and 20 μM in LPS-stimulated beas-2b cells, indicating their potential anti-inflammatory activity.