BIO204 Final Term Mega File by Biotech Brainy Bunch

SHORT QUESTIONS

Q1. Differentiate between quasi steady state and steady state of chemo stat. Also write the effect on the value of Y, U, max, Ks?

The major difference between steady state of chemo stat and quasi steady state of fed-batch culture is that 𝜇 is constant in the chemostate but decrease in fed batch Fed batch quasi steady state change over the time of the fermentation. Product concentration in a fed batch system over the time of fermentation will be dependent on the relationship between qp and 𝜇 (Hence D).

Quasi Steady State:

Steady State:

However, if an overflow device were fitted to the fermenter such as that the added medium displaced an equal volume of culture from the vessel then continuous production of cells could be achieved. If medium id fed continuously to such a culture at a suitable rate, steady state is achieved eventually, that is formation new biomass by the culture is balanced by the loss cells from the vessels.

Effects on Values of Y, U, max, Ks:

The characteristics of an organisms and (therefore its behavior in a chemo stat) are described by the numerical values of the constant Y, 𝜇max and Ks. The value of Y affects the steady

be employed and the values affects the residual substrate concentration (and hence, the biomass concentration) and also the maximum dilution rate that may be used.

2. Differentiate between axial and radial flow / basic

classification?

Axial Flow: · BIO204 FINAL TERM SUBJECTIVE MEGA FILE · GROUP: BIOTECH BRAINY BUNCH · ALL DATA FROM PAST PAPERS (2018-2022) · ADMINS: MEHWISH MUGHAL & BELLA

Axial flow impellers have low shear properties. The angle pitch of the agitators coupled with the thin trailing edges of the impeller blades reduce formation of the eddies in the wake of the moving blades. Axial flow impellers are pitched in an angle and thus direct the liquid flow towards the base of the bank. Example of axial flow mixing is considerably more energy efficient than radial flow mixing. They are more effective at lifting solids from the base of the tank.

Radial Flow:

As the high shear region exists only at the tip, the overall shear condition in the reactor is lower than would be generated by the radial flow impeller such as Rushton Turbine. Intermig impellers are used widely for agitation and aeration in fungal fermentation. High shear is effective at breaking up bubbles. For this reason, radial flow impellers are used for the culture of the aerobic bacteria.

3. Write down four accessories of fermentation

process?

Accessories for a Fermenter

1. Baffle
2. Sterile compressed air (at 1,5 to 3.0 atmospheres)
3. Chilled water (12 to 15°C)
4. Cold water (4°𝐶)
5. Hot water
6. Steam (High Pressure)
7. Steam Condensate
8. Electricity
9. Stand- by generator
10. Drainage of effluents
11. Motors
12. Storage facilities for media component

Q4. Convert Monod equation into linear equation?

The Monod equation is 𝑆

This tells us that specific growth rate is generally found to be function of the three parameters

1. The concentration of growth limiting substrate (S)
2. The maximum specific growth rate (𝜇max)
3. A substrate-specific constant Ks 𝑆

Taking the reciprocal values in the Monod equation and rearranging it

𝜇

1 = 𝑆

𝜇

1 =

𝜇

1 =

𝜇

This equation is fit in linear form as Y = a + bx Now by considering a =

Hence, the linear equation is , b = and 1 is the yield which is represented as Y. 𝜇

1 =

𝜇 𝜇