Effects of different stirrers on laccase production with Cerrena unicolor

Abstract:

[Objective] To study the effects of different stirrers on laccase production with white-rot fungus Cerrena unicolor Y-G07 during fermentation. [Methods] Y-G07 is a non-spore forming filamentous fungus, whose laccase synthesis is coupled with its cell growth. Considering the aerobic nature and shear force sensitivity of the strain, five different stirrers were designed to compare the effects on hyphal morphology, growth rate, dissolved oxygen, glycometabolism and laccase production. [Results] Different stirrers resulted in the difference in hyphal morphology, cell concentration, growth cycle, and thus affected laccase production. The six-hinge-blade DT602 impeller formed reticular mycelia with appropriate density, high concentrations of mycelium cells and less hypha fracture during fermentation. The laccase production was increased up to 690 U/mL, which is 54% higher than that by using usual Six-flat-blade impeller. [Conclusion] Proper design of agitator in fermentor can be favorable for aerobic and shear-force sensitive microorganisms.