Antimicrobial compounds from Athyrium sinense damage the cell membrane of Clavibacter michiganensis subsp. sepedonicus

  • Jin Cai Institute of Applied Chemistry, Shanxi University, Taiyuan, China
  • Beibei Du School of Life Science, Shanxi University, Taiyuan, China
  • Le Kang Shanxi Academy of Analytical Sciences, Taiyuan, China
  • Junjun Guo Shanxi Academy of Analytical Sciences, Taiyuan, China


Clavibacter michiganensis subsp. sepedonicus is a widely distributed pathogen that causes ring rot of potato. Antimicrobial activity assays demonstrated that petroleum ether extracts from Athyrium sinense was a fraction with strong activity against C. michiganensis subsp. sepedonicus. The aim of this study was to determine the chemical compounds in this fraction, and to investigate the antimicrobial mechanism. The dominant components were palmitic acid (25.78%), neophytadiene (13.66%), linoleic acid (8.95%), oleic acid (8.20%), phloretic acid (7.48%), methyl sinapate (6.92%), e-11-hexadecen-1-ol (6.10%), 1-hexadecanol (5.41%), and stearic acid (2.87%). Electron micrographs showed that application of the petroleum ether extracts seriously altered the morphology of C. michiganensis subsp. sepedonicus. Release of alkaline phosphatase and leakage of intracellular soluble protein confirmed that the integrity of the cell membrane was destroyed. Furthermore, ATPase activity, intracellular DNA content, and cell membrane potential were all demonstrated to be inhibited. In addition, the petroleum ether extract penetrated through the damaged cell membrane, and subsequently disrupted the cell cycle of the bacteria. We concluded that the petroleum ether fraction of ethanolic Athyrium sinense extracts was effective to inhibit C. michiganensis subsp. sepedonicus by damaging the cell membrane, and could be used as a natural alternative for C. michiganensis subsp. sepedonicus control.

Plant microbiology and phytopathology