123457890

1. Fermentation

2. Fermentation
• Submerged fermentation (Smf)/ Liquid
fermentation (Lf)
• Solid state fermentation (SSF)

3. Submerged fermentation
• Media concentration is very much lower as
compared to water content.
• Required processed ingredients are
expensive
• Higher water activity becomes the major
cause of contamination in SLF
• Large-scale bioreactors are required
because media is very much diluted.

4. • High air pressure consumes more power
and there is poor transfer of gas in SLF
• Vigorous mixing makes diffusion easy.
• Online sensors are available and sampling
is easy for biomass measurement.
• Water makes downstream process difficult
and very expensive.
• High quantity of liquid waste is produced,
causes difficulties in dumping

5. Solid state fermentation (SSF)
• Organisms requiring less water for growth
are preferred such as filamentous fungi.
• Inert support (natural or artificial),
containing all components for growth in
the form of solution
• Less chances of contamination because of
low availability of water
• Small size bioreactors can be used.

6. • Less consumption of energy for aeration
and gas transfer.
• Limiting factor for growth is diffusion of
nutrients
• Lots of difficulties in measuring the
quantity of biomass present and other
online processes
• Downstream processing is easy, cheaper
and less time consuming.
• Liquid waste is not produced

7. Fermentation Process
• Batch
• Fed batch
• Continuous

8. Batch Fermentation
• Fermentation Kinetics
• μ (h-1): Specific growth rate dx/dt
• Yx/s: g of cell biomass formed/g of substrate
consumed
• Yp/x: Product produced/g of cells formed
• Yp/s: Product produced/g of substrate consumed

9. Continuous Fermentation
• Homogeneously mixed Bioreactor
• Chemostat or turbidostat
• Chemostat- growth controlled by adjusting conc.
Of substrate
• Turbidostat- cell growth kept constant, by using
turbidity to monitor biomass conc.
• Plug flow Reactor- solution flows through tubular
reactor

11. Fermentation classification
• Type 1- product directly derived from primary
metabolism. E.g. SCP, Ethanol
• Type II- product also derived from substrate,
but production takes place in secondary
pathway e.g. citric acid
• Type III- primary metabolism function first,
accompanied by substrate consumption, growth,
product is formed by intermediary metabolism
e.g. Antibiotics

13. Flask Fermentation
• Lab Scale

14. Fermenter
• Height and width
2:1-6:1
• 4-12 baffles
1:10-1:12
• 4-8 radial blades
• SS jacket 316, 317

15. Impeller

16. Sterilization
• In situ
• Ex situ

18. Air Lift fermenter