The Optimum Culture Condition for the Increasement of Biosurfactant Produced by Pseudomonas aeruginosa F722

The hydrogen-producting bacterium was isolated from fresh water and identified as Enterbacter cloacae. The isolated was named Enterobacter cloacae YJ-1. In batch culture, The optimum cultivation temperature and pH of strain YJ-1 was 35$^{\circ}C$ and 7.5, respectively. All of the added glucose was consumed completely during fermentation even though pH was not controlled. Amount of hydrogen produced on each condition of 2% glucose, 4% sucrose and 5% fructose was 950, 1000 and 948 mL/L, respectively and resulted in increasing hydrogen production approximately 2.5-times more than controlled condition. The macimum hydrogen production was obtained when 50mM phosphate was added. was obtained when 50mM phosphate was added. In repeated0batch culture, yeast extract, but the production amount was not changed on the condition of over 0.5%, Most of the organic acides produced during the fermentation were formic and acetic acid, and propionic acid was moiety also generated.

생물계면활성제 생산증가를 위한 Pseudomonas aeruginosa F722의 최적배양조건

P. aeruginosa F722는 탄화수소를 분해하는 과정에 biosurfactant (BS)를 생산한다. 탄화수소 분해에 사용되는 C-배지에서 BS 생산량은 0.78 g/ $\ell$이었으나, 질소원과 탄소원을 각각 0.05% (w/v) NH$_4$Cl + 0.1% (w/v) yeast extract과 3.0% (w/v) glucose로 조정한 경우는 BS 생산량이 1.66 g/ $\ell$로 증가하였다. 최적의 BS 생산조건으로 배양하는 동안 air 1.0 LPM를 공급해 주었을 때는 공기를 공급하지 않을 때의 1.66 g/ $\ell$보다 약 20% 증가한 1.94 g/ $\ell$이었다 뿐만 아니라, glucose 분해속도는 대수증식기와 정지기에서 air를 공급하지 않은 경우 0.25, 0.18 h$^{-1}$ 였으나, 공기를 1.0 LPM으로 공급한 경우 0.33, 0.29 h$^{-l}$ 로 조사되었다.