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Consider the growth of a microorganism in batch culture. When the substrate concentration is high, the cell density doubles every 0.75 h, the observed substrate yield coefficient is 0.3 g DCW/g, and substrate consumption is allocated towards biosynthesis (60%), maintenance (10%), as well as product formation (30%). The product formation is strictly growth-associated. The batch reactor is inoculated with 0.01 g DCW/L and 10 g/L substrate. Estimate the maximum cell density (after lag phase).

Consider the growth of a microorganism in batch culture. When the substrate concentration is high, the cell density doubles every 0.75 h, the observed substrate yield coefficient is 0.3 g DCW/g, and substrate consumption is allocated towards biosynthesis (60%), maintenance (10%), as well as product formation (30%). The product formation is strictly growth-associated. The batch reactor is inoculated with 0.01 g DCW/L and 10 g/L substrate. Estimate the maximum cell density (after lag phase). Correct Answer 1.81 g DCW / l

Xfromsubstrate = (10 g substrate/L).(0.6).0.3 g DCW/g Substrate = 1.8 g DCW/l Xmax = Xo + Xfromsubstrate = 0.01 g DCW/l + 1.8 g DCW/l = 1.81 g DCW/l.

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