Purification, characteri̇zation and inhibition properties of peroxidase from haricot bean (Phaseolus vulgaris L.)

Since peroxidases have effects on various industrial and biochemical fields, purification and characterization studies are continuing. In this study, peroxsidase enzyme (POD) was purified from bean (Phaseolus vulgaris L.) using different techniques, Kinetic characteristics were determined and inhibition study was performed. POD from haricot bean was purified using (NH4)2SO4 precipitation, dialysis, CM-Sephadex and anion exchange chromatography. SDS-PAGE was performed to check the purity of the purified POD enzyme and to determine the molecular mass. The molecular mass was found to be 45 kDa. The optimum pH, optimum ionic strength, optimum temperature and stabil pH for POD were determined as 5.0, 0.3 M, 30 ºC, 5.0 in crude extract, respectively. Km and Vmax values were calculated by plotting Lineweaver-Burk graph. The Km values of the enzyme for the guaiacol and H2O2 substrates were determined as 0.0154 and 0.065, respectively. The inhibitory effects of CTAB (cetyl trimethylammonium bromide), EDTA (ethylenediaminetetraacetic acid), citric acid and sodium azide on POD enzyme were examined and the highest inhibitory effect was observed for sodium azide (99% inhibition).