New diphenyl ethers from a fungus Epicoccum sorghinum L28 and their antifungal activity against phytopathogens

Bioorg Chem. 2021 Oct:115:105232. doi: 10.1016/j.bioorg.2021.105232. Epub 2021 Aug 2.

Abstract

The strategy "IEMAHC" (Induction of Endophyte Metabolism by Adding Host Components) was applied to the fermentation of the endophytic fungus Epicoccum sorghinum L28 from Myoporum bontioides by introducing guaiol, an ingredient of M. bontioides, into the cultivation medium, which resulted in the purification of nine new diphenyl ethers, epicoccethers A-I (1-9). Their structures were determined by overall spectroscopic analysis. HPLC-MS analysis revealed that compounds 5-7 were products generated by induction of guaiol. Compounds 6 and 7 are the first members containing an ester moiety formed by the natural long-chain fatty acid and the hydroxyl group in the phenylmethanol unit of the diphenyl ether class. The antifungal activities of compounds 1, 2, and 4-7 against Fusarium oxysporum were 1, 1, 2, 1, 2 and 4 times as high as those of the positive control triadimefon, respectively. Compounds 4 and 5 showed 1.6 times the antifungal activities of triadimefon towards Colletotrichum musae.

Keywords: Antifungal activity; Diphenyl ether; Epicoccum sorghinum; Induction fermentation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antifungal Agents / chemistry
  • Antifungal Agents / isolation & purification
  • Antifungal Agents / pharmacology*
  • Ascomycota / chemistry*
  • Colletotrichum / drug effects*
  • Dose-Response Relationship, Drug
  • Fusarium / drug effects*
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Phenyl Ethers / chemistry
  • Phenyl Ethers / isolation & purification
  • Phenyl Ethers / pharmacology*
  • Structure-Activity Relationship

Substances

  • Antifungal Agents
  • Phenyl Ethers
  • phenyl ether

Supplementary concepts

  • Colletotrichum musae
  • Epicoccum sorghinum
  • Fusarium oxysporum