Enantioselective separation and degradation of the herbicide dichlorprop methyl in sediment

Chirality. 2009 Apr;21(4):480-3. doi: 10.1002/chir.20624.

Abstract

Chiral pesticides currently constitute about 50% of all pesticides dosage used in China, and this ratio is increasing as more complex structures are introduced. Dichlorprop methyl (DCPPM) is a chiral herbicide consisting of a pair of enantiomers. In this study, the enantiomeric separation of DCPPM was investigated by gas chromatography (GC) and high-performance liquid chromatography (HPLC) using chiral stationary phases (CSPs), and its enantiomeric degradation was characterized using a DCPPM-degrading bacterial strain isolated from an activated sludge from a textile-printing wastewater treatment plant. Baseline separation by both GC and HPLC was achieved. Incubation with DCPPM-degrading bacteria in different pH solutions showed that the R enantiomer was preferentially degraded over the S enantiomer of DCPPM. The degradation rate constant decreased with increasing pH in the order of k(pH5) approximately k(pH7) >k(pH9). In comparison, the enantioselectivity as indicated by EF followed the order of pH 7 > pH 9-pH 5.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2,4-Dichlorophenoxyacetic Acid / analogs & derivatives*
  • 2,4-Dichlorophenoxyacetic Acid / chemistry
  • Biodegradation, Environmental
  • Buffers
  • Chromatography, Gas / methods
  • Chromatography, High Pressure Liquid
  • Environmental Pollutants / analysis
  • Herbicides / chemistry*
  • Hydrogen-Ion Concentration
  • Pesticides / chemistry
  • Soil Pollutants / analysis
  • Spectrophotometry, Ultraviolet / methods
  • Stereoisomerism
  • Time Factors
  • Water Pollutants, Chemical / analysis
  • Water Purification

Substances

  • Buffers
  • Environmental Pollutants
  • Herbicides
  • Pesticides
  • Soil Pollutants
  • Water Pollutants, Chemical
  • 2,4-Dichlorophenoxyacetic Acid
  • dichlorprop methyl ester