ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Fast method for estimation of the effect of compounds modulating the radical oxidation of sulfhydryl-groups on 4-mercapto-2-nitrobenzoic acid applied as a model substance

A. Breier, T. Stankovičová, V. Ďurišová, and A. Ziegelhőffer

Laboratory of Biotechnology, Centre of Physiological Sciences, Slovak Academy of Sciences, CS-84233 Bratislava

Abstract: Kinetics of radical oxidation of 4-mercapto-2-nitrobenzoic acid was investigated in the presence of hydrogen peroxide and iron(II) sulfate, i.e. SL hydroxyl radicals generating system. Initial velocities of radical reaction were established by numerization of the course of kinetic dependences. The value of initial reaction velocity was used as a criterion for evaluation of efficacy of ethylenediaminetetraacetic acid (EDTA) and ascorbic acid as model compounds slowing down the course of radical oxidations. Acting probably via chelation of the iron(II) ion, EDTA in lower concentrations stimulated but in higher concentrations inhibited the course of radical oxidation of 4-mercapto-2-nitrobenzoic acid. Ascorbic acid representing a typical scavenger substance was found to inhibit the above radical oxidation reaction in the whole range of concentrations tested.

Full paper in Portable Document Format: 434a553.pdf

Chemical Papers 43 (4) 553–559 (1989)