Abstract: Bioconversion of lignocellulosic wastes to higher value products through fungal fermentation has economic and ecological benefits. In this study, to develop an effective strategy for production of manganese peroxidase (MnP) fromcassava residue by Phanerochaete chrysosporiumin solid state fermentation, the stimulators of MnP production were screened and their concentrations were optimized by one-at-a-time experiment and Box-Behnken design. The maximum MnP activity of 186.38 nkat·g^-1 dry mass of the sample was achieved after 6 days of fermentation with the supplement of 79.5mmol·L^-1·kg^-1 acetic acid, 3.21 ml·kg^-1 soybean oil, and 28.5 g·kg^-1 alkaline lignin, indicating that cassava residue is a promising substrate for MnP production in solid state fermentation. Meanwhile, in vitro decolorization of indigo carmine by the crude MnP was also carried out, attaining the ratio of 90.18% after 6 h of incubation. An oxidative mechanism of indigo carmine decolorization by MnP was proposed based on the analysis of intermediate metabolites with ultra-high performance liquid chromatography and gas chromatography tandemmass spectrometry. Using the crude MnP produced fromcassava residue for indigo carmine decolorization gives an effective approach to treat dyeing effluents.

Key words: Cassava residue, Manganese peroxidase, Phanerochaete chrysosporium, Solid state fermentation, Indigo carmine

摘要： Bioconversion of lignocellulosic wastes to higher value products through fungal fermentation has economic and ecological benefits. In this study, to develop an effective strategy for production of manganese peroxidase (MnP) fromcassava residue by Phanerochaete chrysosporiumin solid state fermentation, the stimulators of MnP production were screened and their concentrations were optimized by one-at-a-time experiment and Box-Behnken design. The maximum MnP activity of 186.38 nkat·g^-1 dry mass of the sample was achieved after 6 days of fermentation with the supplement of 79.5mmol·L^-1·kg^-1 acetic acid, 3.21 ml·kg^-1 soybean oil, and 28.5 g·kg^-1 alkaline lignin, indicating that cassava residue is a promising substrate for MnP production in solid state fermentation. Meanwhile, in vitro decolorization of indigo carmine by the crude MnP was also carried out, attaining the ratio of 90.18% after 6 h of incubation. An oxidative mechanism of indigo carmine decolorization by MnP was proposed based on the analysis of intermediate metabolites with ultra-high performance liquid chromatography and gas chromatography tandemmass spectrometry. Using the crude MnP produced fromcassava residue for indigo carmine decolorization gives an effective approach to treat dyeing effluents.

关键词: Cassava residue, Manganese peroxidase, Phanerochaete chrysosporium, Solid state fermentation, Indigo carmine