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Value questions can also be made with the Fill Blanks question type.

The fungus Aspergillus niger is used to produce from glucose a specific enzyme, which is excreted in the medium. The glucose is used by the fungus for growth, maintenance and production (which is not growth-related).

Kinetic parameters:
μmax 0.2 h-1
Ks 0.05 kg∙m-3
qp 0.004 kg∙kg biomass-1∙h-1
Yps 1.2 kg∙kg-1
Yxs 0.43 kg∙kg-1
ms 0.04 kg∙kg-1∙h-1

The enzyme is produced in a fed-batch fermentation in a well-stirred tank of 50 m3 working volume. The fungus is first grown batch-wise in 20 m3. The inoculum is 5 kg and when 800 kg of fungus is reached in this batch-fermentation, the fed-batch is started and lasts for a period of 25 h.

Calculate how much glucose is consumed for product formation during the batch period.

kg