Evaluation of esterases from livers of beef, pig, sheep, monkey and chicken for detection of some pesticides by thin-layer chromatographic-enzyme inhibition technique

[Enzymatic detection of carbamate pesticides on impregnated cellulose plates]

The detection of carbamate pesticides by an enzyme-inhibition method on impregnated (ethylene glycol, triethylene glycol, beta,beta'-oxydipropionitrile) cellulose thin layer plates is described. The enzyme-substrate combination: pig liver esterase-indophenylacetate (chromogenic substrate) was the most sensitive. The following parameters concerning the sensitivity of the method were investigated: enzyme source, substrate, pH, inhibition time, inhibition temperature, thickness of the cellulose layer, stationary phase.

Starch-gel electrophoresis of liver esterases selectively inhibited by pesticides

The studies presented here indicate that selective inhibition of liver esterases or bands by pesticides can be evaluated rapidly by starch-gel electrophoresis. The liver esterase inhibition - starch-gel electrophoretic procedure described may be useful in screening pesticides with selective or specific toxicity to a particular species. A similar method has already been used to demonstrate the relation of esterase inhibition with acute organophosphorus poisoning in pheasants (14). The ability of Dyrene heated in methanol to strongly inhibit liver esterases is noteworthy and will be reported elsewhere.