Tetramic acid derivatives and polyphenols from sponge-derived fungus and their biological evaluation

Abstract

Fifteen compounds, including two tetramic acid derivatives, penicillenol A₁ (1) and penicillenol A₂ (2), six polyphenols containing both phenolic bisabolane sesquiterpenoid and diphenyl ether units, expansols A–F (3–8), together with six phenolic bisabolane sesquiterpenoids (9–14) and diorcinol (15), were isolated from the fermentation broth of the marine-derived fungus ZSDS1-F11 isolated from the sponge Phakellia fusca Thiele collected in the Yongxing island of Xisha. Their structures were elucidated mainly by using extensive NMR spectroscopic and mass spectrometric analyses. Compounds 3–5, 7 and 8 showed potent COX-1 inhibitory activity with IC₅₀ values of 5.3, 16.2, 30.2, 41.0 and 56.8 μM, respectively. Meanwhile, compounds 3–8 showed potent COX-2 inhibitory activity with IC₅₀ values of 3.1, 5.6, 3.0, 5.1, 3.2 and 3.7 μM, respectively. In addition, compound 1 exhibited antituberculosis activity with 96.1% inhibition at concentration of 10 μM.

Keywords::

• marine fungus
• Phakellia fusca Thiele
• tetramic acid
• polyphenol
• anti-inflammatory activity
• antituberculosis activity

Notes

^1. These authors contributed equally to this work.

Additional information

Funding

This work was supported financially by the National Key Basic Research Program of China (973)’s Project [grant number 2010CB833800], [grant number 2011CB915503], the Open Foundation of the Key Lab of Marine Bioactive Substance and Modern Analytical Technique, SOA [grant number MBSMAT-2013-02], the Open-end Funds of Jiangsu Key Laboratory of Marine Biotechnology, Huaihai Institute of Technology [grant number 2013HS005], the Open Foundation of the Laboratory for Polar Science, Polar Research Institute of China [grant number KP201305], the National High Technology Research and Development Program (863 Program) [grant number 2012AA092104], the National Natural Science Foundation of China [grant number 31270402], [grant number 21172230], [grant number 20902094], [grant number 81202876], [grant number 41176148], [grant number 21002110] and Guangdong Province-CAS Joint Research Program [grant number 2011B090300023], [grant number 2012B091100264].