STUDY ON IMPROVING LACCASE ACTIVITY OF PANUS CONCHATUS BY MUTAGENESIS AND ITS BIOBLEACHING

摘要

In this paper, the mutant strains with higher laccase activity were obtained by protoplast fusion and ultraviolet mutagenesis. 19 mutant strains with higher laccase activity were obtained and the highest laccase activity is 17290 IU/L, which is 7.5 times of that of primary strain. The laccase from mutant was used for biobleaching in OLQP or LQP sequence (laccase/NHA treatment (L), oxygen treatment (O), chelating agent treatment (Q) and hydrogen peroxide bleaching (P)), which showed that the physical properties of pulp was improved in a certain extent. The pulp bleaching capability was improved comparatively after treated by laccase/NHA system. It is proved that protoplast fusion and ultraviolet mutagenesis are effective methods to improve laccase activity of Panus conchatus. The results in our work are significant for laccase of its potential application.