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Refer to Q8 and, calculate the bacteria suffer growth inhibition after copper sulphate is accidently added to the fermentation broth. This causes a reduction in oxygen uptake rate to 3 mmol g-1 h-1. What maximum cell concentration can now be supported by the fermenter?

Refer to Q8 and, calculate the bacteria suffer growth inhibition after copper sulphate is accidently added to the fermentation broth. This causes a reduction in oxygen uptake rate to 3 mmol g-1 h-1. What maximum cell concentration can now be supported by the fermenter? Correct Answer 50 gl-1

Assume that addition of copper sulphate does not affect C*AL or kLa. If qo is reduced by a factor of 12.5/3 = 4.167, xmax is increased to: xmax = 4.167 (12 gl-1) = 50 gl-1 To achieve the calculated cell densities all other conditions must be favourable, e.g. sufficient substrate and time must be provided.

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