Determination of catalase activity using chromogenic probe involving iso-nicotinicacidhydrazide and pyrocatechol

A biocatalatic pathway involving chromogenic probe has been proposed for the determination of catalase activity by means of iso-nicotinicacidhydrazide (INH) and pyrocatechol (PC). The assay is based on the enzymatic consumption of hydrogen peroxide using INH-PC system. The response of the catalase activity was ascertained by the rate of the reaction involving 14.10mM H(2)O(2). On addition of H(2)O(2), INH-PC indicator system formed a chromogenic product with absorbance maxima at 490 nm. Hence the activity of catalase was directly measured by the chromogenic response in the formation of the coupled product. The catalase assay was elaborated by the kinetic response of the INH-PC system. The linearity of the catalase activity and H(2)O(2) was in the range 0.2-7.0 units and 1.76-7.0mM, respectively in 3 ml solution. The catalytic efficiency and catalytic power were calculated. The Michaelis-Menten constant of INH, PC and H(2)O(2) were found to be 0.344, 0.176 and 8.82 mM, respectively. The indicator reaction was applied in the determination of catalase activity in mycelia mats and culture media.