University:
Virtual High School
Course:
SBI4U | Biology
Academic year:

2019
Views:

388

Pages:

4
Author:

Mikki L

CHE 2126: Biochemical Engineering Problem Set 4 Names: Larracas, Mikki P. Ninobla, Karla Marie SJ. Tanpoco, Sebastian Riley T. Section: 4ChE-A Stoichiometry of Cell Growth and Product Formation 1. Acetic acid is produced from ethanol during growth of Acetobacter aceti, which has the composition CH1.8O0.5N0.2. The biomass yield from substrate is 0.14 g/g; the product yield from substrate is 0.92 g/g. Ammonia is used as the nitrogen source. Write the complete balanced reaction. Also, determine the Respiratory Quotient RQ. How does growth in this culture affect the oxygen demand for acetic acid production? 2. Both Saccharomyces cerevisiae yeast and Zymomonas mobilis bacteria produce ethanol from glucose under anaerobic conditions without external electron acceptors. The biomass yield from glucose is 0.11 g/g for yeast and 0.05 g/g for Z. mobilis. In both cases the nitrogen source is NH3. Both cell compositions are represented by the formula CH1.8O0.5N0.2. (a) What is the yield of ethanol from glucose in both cases? (b) How do the yields calculated in (a) compare with the thermodynamic maximum?