research project details
Project Title: Investigate the pathway of imidazolinone degradation by soil
microorganisms
Investigator(s): Jean-Marc Bollag
Sponsor: American Cyanamid Company
Environmental Problem Addressed:
Degradation of imidazolinone herbicides by soil microorganisms.
Research Project Objectives:
Project objectives are:
- Prepare enrichment cultures from soil that has been exposed to high concentrations of imidazolinone for several years. Isolate a highly active organism from this soil.
- Use 13C- or 14C-labeled imidazolinone to study the metabolic degradation pathway of imidazolinone with axenic cultures (bacteria and fungi).
Summary:
Imidazolinone herbicides are relatively new class of chemical compounds that function by inhibiting the action of a key plant enzyme (acetolactate synthase), which stops plant growth, and eventually kills the plant.
Researchers will study the metabolic degradation pathway of radio-labeled imidazolinone with axenic microbial cultures (bacteria and fungi). Various chromatographic techniques such as TLC, GC, and HPLC will be applied to isolate and separate the formed metabolites; the formed metabolites will be identified by spectrometric analyses.
Experiments with culture filtrate of active strains will be conducted to determine whether extracellular enzymes were produced and show activity. The influence of various environmental parameters (oxygen availability, pH, temperature, soil constituents) on imidazolinone degradation by microorganisms will also be investigated. The extent to which detoxification by binding to humic substances occurs will also be explored.