Scale up of Vitamin B_(12) Production by Pseudomonas denitrificans

摘要

A study was performed to scale up vitamin B_(12) fermentation process. It was found that there was an optimum value of OTR(oxygen transfer rate) (20-25mmolO_2/lh) for vitamin B_(12) synthesis by P. Denitrificans 16-6. In experiments, the tip speed of the agitator(V_(tip)) is controlled not more than 2.2m/s so as to minimize the damage of the bacteria. The optimal OTR value was got by adjust the volumetric flow of the air which could be expressed as: Q_(g.l)(V(l,l/V_(l,s))~(-0.12)(Q_(g.s)). At the end of fermentation, the concentration of vitamin B_(12) was 135.93mg/l the 5000-liter fermenter.