A microorganism is grown in a fermenter under steady-state conditions. The microorganism growth follows Monod kinetics and the following stoichiometric equation: C3H6O3 +a O2 +b NH3c biomass + d CO2 + e H₂O Given that the biomass yield is 0.415 grams of biomass per gram of substrate, determine the respiratory quotient.

Explain why the P/O ratio for a given substrate is not necessarily an integer.

Outline the steps involved in the two paths of sulfate assimilation.  Be sure to address the sulfur reduction pathway as a photoassimilation process.

Choose one antioxidant mineral and describe its mechanism of action.

Calculate the equilibrium constant (K'eg) for each of the three reactions at pH 7.0 and 25 °C, using the AGʻ° values given. (a) glucose 6-phosphatase glucose 6-phosphate + H,O glucose + P; AG'° = –13.8 kJ/mol K'eq= (b) B-galactosidase lactose + H,O glucose + galactose AG'O = -15.9 kJ/mol K'eq=

Give an example of sulfur disproportionation.

What percentage of max is obtained when the substrate is present at 80% of the Km? Use two digits in your answer.

The yeast S.cerevisae is cultivated for ethanol production in a 10000 L fermenter operated continuously at steady state. The reactor is fed by a 50 g/L of sucrose, with a feed flow of 400 L/h. Assuming that the yeast growth kinetics follow the Monod model and using the following information:Data: μmax= 0.1h-1 ; Ks=0.5g/L; Yx/s=0.15 g/g; Yp/s=0.45g/g. a) What are the concentrations of biomass, sucrose and ethanol at the exit of the fermenter?b) Calculate the productivity in ethanol (Pp) and sketch the curve of variation of Pp vs. dilution rate.c) In terms of ethanol productivity, would it be more or less advantageous if the reactor were operated with a feed rate of 1200L/h? Justify.

Why is hydrogen sulfide production monitored during fermentation? Why is this end product undesirable in wine production?

roblem 1An aerobic biochemical process uses a CSTR w/o recycle. The feed characteristics are asfollows: Influent substrate concentration, So = 200 mg/L; half- velocity coefficient, Ks = 50mg/L; maximum, specific substrate utilization rate, k = 5 g/g- day; yield coefficient, Y = 0.5g Xa/g substrate consumed; microorganism decay coefficient, b = 0.10 day-1.1. The process goal is the production of active biomass. Determine the hydraulicretention time that the reactor should be operated in order to maximize the reactoractive biomass concentration (Xa). How does this retention time compare with theminimum solids retention time that the system can theoretically be operated?Calculate the solids retention time safety factor.2. Based on the solids retention time for maximum Xa calculated above, estimate theactive biomass concentration (Xa) and the substrate removal efficiency (E, %)