Dissipation of pirimiphos-methyl during wheat fermentation by Lactobacillus plantarum

Lett Appl Microbiol. 2013 Nov;57(5):412-9. doi: 10.1111/lam.12128. Epub 2013 Jul 23.


In this study, the dissipation of pirimiphos-methyl during wheat fermentation by Lactobacillus plantarum was investigated. Sample preparation for GC/MS detection of pirimiphos-methyl residues from fermented wheat substrate was carried out by two steps: extraction with 25 mL of methanol : acetone = 1 : 1 solvent mix for 30 min, followed by clean-up procedure through a glass column with florisil coupled with elution by 25 mL of ethyl acetate : acetone = 4 : 1. To obtain the highest pesticide degradation level, the fermentation conditions were optimized according to response surface methodology. Our results showed that L. plantarum was able to reduce the level of pirimiphos-methyl in wheat. Although pirimiphos-methyl was partially labile during sterilization prior inoculation (~37-50%), and there was also spontaneous chemical degradation of pesticide (~6-11%), overall L. plantarum enhanced degradation from 15 to 34%, that is, to nearly 81%. Additionally, the effect of pirimiphos-methyl on the lactobacilli growth, and efficiency of fermentation, was studied where pirimiphos-methyl inhibit the growth of bacteria in concentrations higher than 5 mg kg(-1), while the presence of pirimiphos-methyl did not overall affect the lactic acid fermentation.

Keywords: degradation; fermentation; lactobacilli; pesticide; wheat.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Fermentation
  • Lactic Acid / metabolism
  • Lactobacillus plantarum / growth & development*
  • Lactobacillus plantarum / metabolism
  • Organothiophosphorus Compounds / analysis*
  • Pesticides / analysis*
  • Triticum / metabolism
  • Triticum / microbiology*


  • Organothiophosphorus Compounds
  • Pesticides
  • pirimiphos methyl
  • Lactic Acid