中国生物工程杂志

To improve the laccase fermentation productivity of Coriolus vericolor, a novel method for laccase fermentation production was proposed in a three-phase bubble column bioreactor with the mycelial pellets under repeated batch process. Under the optimum laccase production conditions, the effects of the added ascorbic acid concentration on laccase activity were investigated and laccase was cultured by adding ascorbic acid in culture medium under repeated batch process. When 1.50mmol/L ascorbic acid was added to the medium, the laccase activity of fermentation broth reached 1557.9 U/mL, which was 1.6 times higher than that of the control (no ascorbic acidwas added). Under the certain condition, laccase was produced repeatedly in 10 batches for 25 days in the repeated batch culture in the bubble column. The maximum laccase activity was 1919.6 U/ml in the fifth batch. In each batch ,the maximum laccase activity were all more than 1000 U/ml. Laccase produced by the method decolorizes indigo blue markedly. The decolorization rate reached 96.7% with 1-hydroxybenzotriazole（HBT） as mediator for 40 min, HBT concentration 0.10% and laccase dosage 100 U/l. The performance of the three-phase bubble column bioreactor is stable, and the mycelial pellets can be used repeatedly to effectively yield laccase by the method in large scale.