Development and Kinetic Validation of Bio-Catalatic Pathway for the Quantification of Catalase Activity Using 3-Methyl-2 Benzothiazolinehydrazone Hydrochloride and Pyrocatechol as a Chromogenic Co-Substrates

A kinetic model describing the assay of catalase (CAT) activity on hydrogen peroxide using pyrocatechol (PC) and 3-methyl-2 benzothiazolinehydrazone hydrochloride (MBTH) is presented. This model is based on the oxidation of PC by H2O2 in presence of catalase to form quinone, which couples with oxidized MBTH resulting in intense red chromogenic product having maximum absorbance at 500 nm. Hence the activity of catalase was directly measured by the formation of the coupled product. The catalase assay was drawn-out by the kinetic response of the MBTH-PC system. The quantification of catalase was linear over 0.14?3.46 EU with a correlation coefficient of 0.996. This assay was adopted for the quantification of H2O2 between 0.60 and 9.62 mM. The catalytic efficiency, catalytic power and catalytic constant (kcat) of the catalase were 1.16 ×106 M-1 min-1, 3.25×10-5 min-1 and 0.1161 min-1respectively. The method was tested with some microbes and also compared with L. Goth system.