Effect of Dissolved Oxygen Level on Pristinamycin Fermentation by Streptomyces pristinaespiralis

摘要

The effect of different dissolved oxygen (DO) level on pristinamycin fermentation by Streptomyces pristinaespiralis was investigated in a 5-L bioreactor. The results showed that higher DO level of 70%～80% was favorable for the mycelium growth, and that the lower DO level of of 30%～40% was favable for pristinamycin production. Therefore, a two-stepwise oxygen supply strategy was proposed to maintain the DO level of 70%～80% in the first 36 hours during the fermentation, then to decrease the DO level to be of 30%～40% till the end of fermentation. Under this strategy, the yield and the productivity of pristinamycin and 80% respectively, comparing with those at constant DO level of 30%～40%.