The overall yield of a product on a substrate in some bioreactions is the absolute value o...

The overall yield of a product on a substrate in some bioreactions is the absolute value of the production rate divided by the rate of consumption of the feed in the substrate (the liquid containing the cells, nutrients, etc.). The overall chemical reaction for the oxidation of ethylene (C2H4) to epoxide (C2H4O)is

2C2H4 + O2 → 2C2H4O  (a)

Calculate the theoretical yield (100% conversion C2H4) of C2H4O in moles per mole for Reaction (a).

The biochemical pathway for the production of epoxide is quite complex. Cofactor regeneration is required, which is assumed to originate by partial further oxidation of the formed epoxide. Thus, the amount of ethylene consumed to produce 1 mole of epoxide is larger than that required by Reaction (a). The following two reactions, (b1) and (b2), when summed approximate the overall pathway:

C2H4 + O2 + NADH + H+ → C2H4O + H2O + NAD+  (b1)

0.33C2H4 + 0.33O2 + NAD+ + 0.67H2O + 0.33FAD+ → 0.67CO2 + NADH+ +.33H+ + 0.33FADH  (b2)

1.33C2H4+ +.33O2 + 0.33FAD+ → C2H4O + 0.33H2O + 0.67CO2 + 0.33H+ + 0.33FADH  (b3)