Enhanced degradation in soil of the herbicide EPTC and determination of its degradative pathway by an isolated soil microorganism

Thesis/Dissertation · Fri Jan 01 00:00:00 EST 1988

OSTI ID:7164544

Ankumah, R O

A series of experiments was conducted to examine the ability of Ohio soils to develop enhanced degradation of the herbicide EPTC (s-ethyl N,N-dipropyl carbamothiaote) and to determine its metabolism by an isolated soil microorganism. Three soils selected to obtain an range in pH, texture, and organic carbon were treated with EPTC for 4 consecutive applications (6 weeks between applications). EPTC concentrations as measured by gas chromatography, decreased 80% or more one week after the second application in all three soils. Metabolism of unlabelled and labelled EPTC by an isolated soil microbe was followed by GC/MS and TLC/LSC analysis, respectively. Rapid decrease in 14-C activity in the organic fraction corresponded with rapid {sup 14}CO{sub 2} evolution and transient increase in 14-C activity in the aqueous fraction. Four metabolites were observed in the TLC analysis. Two were identified as EPTC-sulfoxide and N-depropyl EPTC with N-depropyl EPTC being confirmed by GC/MS analysis. The availability of different pathways for EPTC metabolism by soil microbes after repeated applications to the soil results in its very rapid degradation and loss of efficacy.

• Research Organization: Ohio State Univ., Columbus, OH (USA)
• OSTI ID: 7164544
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
HERBICIDES
METABOLISM
BIOLOGICAL AVAILABILITY
BIOLOGICAL PATHWAYS
CARBON 14 COMPOUNDS
CARBON DIOXIDE
GAS CHROMATOGRAPHY
MASS SPECTROSCOPY
SOILS
TRACER TECHNIQUES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHROMATOGRAPHY
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PESTICIDES
SEPARATION PROCESSES
SPECTROSCOPY
560300* - Chemicals Metabolism & Toxicology
550501 - Metabolism- Tracer Techniques