A new steroid with 7β,8β-epoxidation from the deep sea-derived fungus Aspergillus penicillioides SD-311

Abstract

7β,8β-epoxy-(22E,24R)-24-methylcholesta-4,22-diene-3,6-dione (1), a new steroid, along with five known analogues (2–6), was isolated from the deep sea-derived fungus, Aspergillus penicillioides SD-311. Strikingly, 1 possessed a rare 7,8-epoxidation moiety. Meanwhile, this is the first time to report natural products from this fungus species. The structures were established by extensive spectroscopic analysis. The absolute configuration was determined by X-ray diffraction experiments. Compound 1 showed antibacterial activity against Vibrio anguillarum with MIC value of 32.0 µg/mL, while 2 displayed inhibitions against Edwardsiella tarda and Micrococcus luteus with MIC values both of 16 µg/mL.

Graphical abstract

Keywords:

• Aspergillus penicillioides
• deep sea-derived fungus
• 7β,8β-epoxy steroid
• marine natural products

Acknowledgments

B.-G. Wang acknowledges the support of the Research Vessel KEXUE of the National Major Science and Technology Infrastructure from the Chinese Academy of Sciences (KEXUE2018G28) and the Taishan Scholar Project from Shandong Province.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research work was financially supported by the Strategic Priority Research Program of Chinese Academy of Sciences, Grant No. XDA22050401, the Aoshan Scientific and Technological Innovation Project of Qingdao National Laboratory for Marine Science and Technology (No. 2016ASKJ14), and the National Natural Science Foundation of China (31700043).