Effect of glucose oxidase on decolorization efficiency of crystal violet by Phanerochaete chrysosporium cultures

Abstract

An enzymatic reaction using glucose oxidase (GOx) was applied for continues production of hydrogen peroxide and organic acid in Phanerochaete chrysosporium cultures for use simultaneously in catalytic cycle of peroxidases. Decolorization efficiency of crystal violet (CV) as a model pollutant was investigated in 16 d old cultures which overproduced manganese peroxidase (MnP) in response to daily GOx addition and control cultures (i.e. no GOx was added). However, the ability of overproduced cultures in decolorization of CV was not increased significantly, through addition of GOx (300 U/L) + glucose (10 Mm) to the culture medium at the start of decolorization, the time needed to obtain 87 ± 0.5% removal of CV was reduced 10.7-fold in compared with the control culture. The best GOx concentration in culture medium for more efficient decolorization was obtained to be 300 U/L. These findings indicated that GOx in the presence of glucose could increase the degradation of CV not only by inducing ligninolytic activity in cultures but also as a subsidiary source for in situ H2O2 and organic acid production for catalytic activity of peroxidases in P. chrysosporium cultures.