Optimization Technology of β-Mannanase Fermented by Pichia pastoris

The fermentation conditions of genetically engineered Pichia pastoris for β-Mannanase were studied. Basic conditions of the carbon source, immunization rates, temperature, p H were optimized in shake-flask. The tests in 30 L fermenter was applied to study the effects of DCW,methanol concentration and DO on enzyme production. Through the orthogonal design to optimize the fermentation conditions. The results indicated that the optimum conditions were as follows :10% inoculum size,30 g / L initial glucose concentration, 10%~20% DO,p H 5.0 at 28 ℃. The dry cell weight was 135 g / L,the target protein concentration could reach to 5.04 g / L. And the β-Mannanase activity got to be 29 600 U / m L,which was 24 times of that the results in the shake flask under these conditions.