A strain of Escherichia coli has been genetically engineered to produce human protein. A batch culture is started by inoculating 12 g cells into a 100-1itre bubble-column fermenter
containing 10 g l- 1 glucose. The maximum specific growth rate of the culture is 0.9 h- 1; the biomass yield from glucose is 0.575 g g -1 .
(a) Estimate the time required to reach stationary phase.
(b) What will be the final cell density if the fermentation is stopped after only 70% of the substrate is consumed?