ABSTRACT
One of the most interesting methods for the detoxification of sulfur mustard is enzyme-catalyzed oxidation. This study examined the oxidative destruction of a sulfur mustard by the enzyme chloroperoxidase (EC 1.11.1.10). Chloroperoxidase (CPO) belongs to a group of enzymes that catalyze the oxidation of various organic compounds by peroxide in the presence of a halide ion. The enzymatic oxidation reaction is affected by several factors: pH, presence or absence of chloride ion, temperature, the concentrations of hydrogen peroxide and enzyme and aqueous solubility of the substrate. The optimum reaction conditions were determined by analyzing the effects of all factors, and the following conditions were selected: solvent, Britton-Robinson buffer (pH=3) with tert-butanol (70:30 v/v); CPO concentration, 16U/mL; hydrogen peroxide concentration, 40mmol/L; sodium chloride concentration, 20mmol/L. Under these reaction conditions, the rate constant for the reaction is 0.006s(-1). The Michaelis constant, a measure of the affinity of an enzyme for a particular substrate, is 1.87×10(-3)M for this system. The Michaelis constant for enzymes with a high affinity for their substrate is in the range of 10(-5) to 10(-4)M, so this value indicates that CPO does not have a very high affinity for sulfur mustard.
Subject(s)
Chloride Peroxidase/metabolism , Mustard Gas/metabolism , Buffers , Catalysis , Chemical Warfare Agents/chemistry , Chemical Warfare Agents/metabolism , Chemical Warfare Agents/toxicity , Hydrogen-Ion Concentration , Kinetics , Metabolic Detoxication, Phase I , Mustard Gas/chemistry , Mustard Gas/toxicity , Oxidation-Reduction , Temperature , tert-Butyl AlcoholABSTRACT
A block of yperite fished up from the Baltic Sea was analysed by gas chromatography coupled with atomic emission spectrometry and mass spectrometry. In the samples of the block about 50 compounds were detected, out of which 30 were identified. The identification of the compounds was performed by using the element chromatograms of the investigated compounds, and the data obtained by mass spectrometric detection. Thiodiglycol was not found among the compounds present in the investigated block. The calculations of the contents of sulphur mustard and some products in the block were performed by an external calibration method using bis(2-chloroethyl) sulphide as the standard. A satisfactory precision of elements determinations was obtained (RSD from 4.4 to 14.3%).
