Pengaturan Laju Oksigenasi untuk Meningkatkan Ketahanan Sel Rekombinan Escherichia coli pada Kultivasi Etanol Tinggi

Abstract

The cell tenacity improvement of Escherichia coli recombinant under high ethanol culture conditions by arrangement oxygenation rate was investigated in this study. Dry cell weight, glucose, and acetate production were analysed to show the effect of this treatment. E. coli cells were grown in 25 and 50 ml of medium with 250 rpm agitation which shown the high and low oxygenatian rate. Cultivation taken a place during 24 hours aerobically with ethanol addition into the culture time of t = 6 h. Improvement of oxygenation rate under high ethanol culture condition could increase the cell growth until 56%. Improvement of oxygenation rate also decreased the acetate production from 6.27 g/l to 4.45 g/l. This acetate production was ralated with overflow metabolism phenomenon. Improvement of oxygenation rate intent on improvement TCA cycle activity for increasing cell growth and repairing cell structure by producing glutamate. The glutamate (2 g/l) was added to confirm the effect of improvement oxygenation rate on cell tenacity. Improvement of oxygenation rate and glutamate addition resulted in carbon flux in TCA cycle was over capacity. It caused the carbon was accumulated and was used for acetate production