GNPS-based mass spectrum-molecular networks is an effective strategy for rapidly identifying known natural products and discovering novel structures. The chemical diversity of azaphilones from the fermentation extracts of Talaromyces sp. HK1-18 was studied by molecular network technique. Three linear tricyclic azaphilones, sequoiamonacins A-C (2a, 2b, 1), were isolated by silica gel column chromatography and high performance liquid chromatography from the extracts of the fungal strain of HK1-18, and their structures were identified by nuclear magnetic resonance and high-resolution mass spectrometry. Guided by the mass spectra of sequoiamonacins A-C (2a, 2b, 1), the cluster of sequoiamonacinoid analogues was discovered from the full molecular networking of HK1-18. By analyzing the MS/MS fragments of each parent ion in this cluster, 7 azaphilones (3-9) included 6 new ones (4-9) were predicted successfully. Then the MS/MS cracking regularity of this type of azaphilones was revealed. Compound 1 showed anti-inflammatory activity, which can inhibit the production of interleukin-1α (IL-1α) in lipopolysaccharide (LPS)-induced mouse macrophage RAW264.7, with an inhibitory rate of 29% at the concentration of 12.5 μg·mL-1.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |