Anti-inflammatory polyketides from the endophytic fungus Talaromyces aculeatus A884.

Chemical investigation on the EtOAc extract of endophytic fungus Talaromyces aculeatus A884 led to the isolation of one undescribed γ-butyrolactone aculeatone A (1), one rubralactone aculeatone B (2), and one polyester aculeatone C (5) together with 12 known compounds. Their structures were unambiguously elucidated by extensive spectral analyses. The absolute configurations of aculeatones A-B were assigned by the comparison of their experimental and calculated ECD data. In addition, all of the isolates (1-15) were evaluated for their anti-inflammatory activities by measuring the inhibition of LPS-induced NO production in RAW 264.7 macrophages. Compounds 2, 9-11 exhibited significant anti-inflammatory activity with IC50 values ranging from 24.17 to 29.56 μM, comparable with the positive control indomethacin (IC50 = 29.44 μM). Further biological assessment showed that compound 2 displayed acetylcholinesterase (AChE) inhibitory activity with an IC50 of 18.43 μM. Molecular docking simulations provided preliminary insights into the binding interactions between the new compound 2 and target proteins (iNOS and AChE).