Enhanced production of cellobiase by marine bacterium Cellulophaga lytica LBH-14 from rice bran under optimized conditions involved in dissolved oxygen

The optimal conditions for production of cellobiase by C. lytica LBH-14 at flask scale had been previously reported. In this study, parameters involved in dissolved oxygen in 7 and 100 L bioreactors were optimized for pilot-scale production of cellobiase. The optimal agitation speed and aeration rate for cell growth of C. lytica LBH-14 were 400 rpm and 1.11 vvm in a 7 L bioreactor, whereas those for production of cellobiase were 330 rpm and 0.70 vvm. The analysis of variance (ANOVA) implied that significant factor for cell growth was the aeration rate, whereas those for production of cellobiase were the aeration rate as well as the agitation speed. The optimal inner pressures for cell growth and production of cellobiase by C. lytica LBH-14 in a 100 L bioreactor were 0.00 and 0.06 MPa, respectively. The maximal production of cellobiase in a 100 L bioreactor under optimized conditions using rice bran was 140.1 U/mL, which was 1.52 times higher than that in a flask scale.