CH3104: Sketch the Eadie–Hofstee plot of the Following data for both Uninhibited and Inhibited Enzymatic Reactions: Biochemical Engineering Assignment, NTU, Singapore

1. Sketch the Eadie–Hofstee plot of the following data for both uninhibited and inhibited enzymatic reactions. Please label the x-axis and y-axis. For each reaction, label the x-intercept, y-intercept, and slope of the line with the numerical values with units. Determine Vmax (5 marks), Vmax, app (this is Vmax under inhibitor treatment, 5 marks), Km (5 marks), and Km, app (this is Km under inhibitor treatment, 5 marks) with their units. What type of inhibitor is this (10 marks, must give a reason)? What is KI for this inhibitor with units?

2. Zymomonas mobilis is a bacterial strain that can be used for ethanol conversion. The equation for ethanol production from glucose is:
𝐶6𝐻12𝑂6 → 2 𝐶2𝐻5𝑂𝐻 + 2 𝐶𝑂2.

In a batch reactor, Z. mobilis cells were inoculated to culture media that contained 20 g/L glucose. After some time, the glucose concentration reduced to 3 g/L, and the ethanol concentration was 6.7 g/L. How does the overall yield of ethanol from glucose compare with the theoretical yield (% of the theoretical value)?

3. Pichia pastoris, a methanol-consuming yeast, is cultured in a 20𝑚3 stirred fermenter for recombinant protein expression. In this fermentation system, the volumetric oxygen transfer coefficient (𝑘𝐿𝑎) was 0.17𝑠 −1. The saturated dissolved oxygen concentration in the culture media was determined to be 8 × 10−3 𝑘𝑔𝑚−3. Considering the specific rate of oxygen consumption is 12 𝑚𝑚𝑜𝑙 𝑔 −1ℎ −1 , please estimate the maximum possible cell concentrations.

4. A chemostat bioreactor (200 𝑚3) is used for culturing fungus Aspergillus oryzae. The glucose concentration in the feed stream is 20 𝑔 𝐿 . 𝐾𝑆 and 𝜇𝑚𝑎𝑥 for A. oryzae are 0.1𝑔𝐿and 0.2 ℎ−1, respectively. (a) Find out the flow rate needed to reach a steady-state concentration of glucose at 0.3 𝑔 𝐿 in the bioreactor, and (b) if the cell concentration and the yield coefficient of the culture at steady-state is 6 𝑔 𝐿 and 0.6 𝑔 𝑔, respectively. Find out the steady-state substrate concentration.