microbial toxicity assessment and biodegradation of triclopyr using arthrobacter globiformis and pseudomonas pictorum
abstract
triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) was investigated for
biodegradation using arthrobacter and pseudomonas sp. bacteria. no
evidence of the proposed major metabolite, 3,5,6-trichloro-2-pyridinol was
found in sole carbon source or enriched growth medium experiments.
triclopyr, and various salts of triclopyr were also tested for toxicity using a
modified int reduction method which relied upon the enzymes from dead,
lysed cells in the mature culture. the ec50 values for arthrobacter and
pseudomonas sp. bacteria were found to be 46 and 470 ppm respectively
for triclopyr. the proposed major metabolite 3,5,6-trichloro-2-pyridinol was
found to be considerably more toxic to both bacteria than triclopyr. the ec50
results were compared to those for 2,4-d and picloram using the same
method. analysis of triclopyr by gas chromatography and
nuclear magnetic resonance was investigated in order to
simultaneously quantitate the herbicide and its proposed major
metabolite. synthesis of triclopyr using various starting
materials was also investigated to achieve an efficient
laboratory scale synthesis. different synthetic routes will be
useful for further studies which may make use of radiolabeled
triclopyr since selective inclusion of the radiolabeled depends on
the synthesis used.
collections
- retrospective theses [1604]