Pinolide, a new nonenolide produced by Didymella pinodes , the causal agent of ascochyta blight on Pisum sativum

J Agric Food Chem. 2012 May 30;60(21):5273-8. doi: 10.1021/jf300824d. Epub 2012 May 18.

Abstract

An aggressive isolate of Didymella pinodes isolated from pea ( Pisum sativum ) produced four different metabolites in vitro. The metabolites isolated from the culture filtrates were characterized by spectroscopic and optical methods. A new nonenolide, named pinolide, was isolated and characterized as (2S*,7R*,8S*,5E,9R*)-2,7,8-trihydroxy-9-propyl-5-nonen-9-olide. Pinolidoxin, the main toxin produced by D. pinodes, was also isolated together with two other closely related nonenolides, identified as herbarumin II and 2-epi-herbarumin II. Herbarumin II and 2-epi-herbarumin II have been previously isolated from the fungi Phoma herbarum and Paraphaeosphaeria recurvifoliae , respectively, but described here to be isolated for the first time from D. pinodes. When tested on leaves of the host plant and other legumes and weeds, pinolidoxin was phytotoxic in all of the plant species, whereas the other three nonenolides did not produce any symptoms. The importance of the stereochemistry of the hydroxy group at C-7 on phytotoxicity also is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascomycota / chemistry
  • Ascomycota / metabolism*
  • Molecular Structure
  • Mycotoxins / chemistry
  • Mycotoxins / metabolism*
  • Pisum sativum / microbiology*
  • Plant Diseases / microbiology*

Substances

  • Mycotoxins