Effect of Dissolved Oxygen on the Growth of Azotobacter vinelandii UWD and Production of PHBV in the Mixture of Organic Acids and Glucose

유기산 및 포도당 혼합배지에서 Azotobacter vinelandii UWD의 생장 및 PHBV 생산에 대한 용존산소의 영향

In both 7L and 20L fermentor experiments the level of dissolved oxygen (D.O) strongly affected growth and PHBV production of Azotobacter vinelandii UWD. A higher D.O. increased carbon substrate consumption rate and cell growth rate with a similar residual biomass production. However, a lower D.O. was a much better condition for PHBV production. In a 20L fermentor experiments controlled at 5% D.O. cell growth rate was about twice faster(0.555 hr-1 and 0.260 hr-1 at the acid and the glucose phase, respectively) with an equal amount(4.5 g/L) of residual biomass production. However, PHBV content in the cell(62.3 wt%) increased 17.3 times at 1% D.O.