Screening of lignin degrading enzyme high-producing strain from white rot fungi

To decompose the fiber structure of wheat bran effectively, 9 strains of white rot fungi producing lignin degrading enzyme were screened. Firstly, the guaiacol plate method was used for preliminary screening to obtain 5 strains with high laccase activity. Secondly, the enzyme activities of lignin peroxidase, manganese peroxidase and laccase secreted by the 5 strains were compared. Finally, two strains with relatively high enzyme activity were used to ferment wheat bran, and one strain AP3 with relatively high enzyme activity and high wheat bran fiber degradation rate was obtained. After 15-day liquid culture, the activities of lignin peroxidase, manganese peroxidase and laccase were up to 119.42 U/mL, 124.35 U/mL and 173.45 U/mL, respectively, and the lignin degradation rate of wheat bran reached 36.24% after 15-day liquid fermentation. The study lays a foundation for further study on the degradation mechanism of wheat bran fiber by white rot fungi.