1. DOWNSTREAM PROCESSING

2. DOWNSTREAM PROCESSING
The separation and purification of desired fermentation product is downstream processing or bioseperation.
Steps involved in downstream processing are –
Removal of insoluble's
Product Isolation
Product Purification

3. Removal of Insoluble’s
It is the first and the crucial step in downstream processing
It includes separation of cells, cell debris or other particulate matter from fermentation broth
Separation by Filtration or Centrifugation

4. FILTRATION
Filtration separates particles by forcing the fluid through a filtering medium on which solids are deposited

5. FILTRATION
The two types of filters –
filter press and rotary drum filters.
A filter press is often employed for the small-scale separation of bacteria and fungi from broths.
For large-scale filtration, rotary drum filters are usually used.

6. CENTRIFUGATION
It uses the centrifugal force for the separation of mixtures
More-dense components migrate away from the axis of the centrifuge while less-dense components migrate towards the axis

7. Two basic types of centrifuges are – tubular and the disk centrifuge
CENTRIFUGATION
Two basic types of centrifuges are –
tubular and the disk centrifuge
Tubular : separation of Two immiscible liquidsClarification of Small Quantities of impurities from liquids
Disk : continuous and

8. CELL RUPTURE
To obtain intracellular products the cells first have to be disrupted to release these into a liquid medium before further separation can be carried out
The cell rupture techniques have to be very powerful, but they must be mild enough so that desired components are not damaged
Physical Methods include mechanical disruption by homogenization, or ultrasonication

9. CELL RUPTURE
Chemical methods include the treatment of cells with detergents, alkalis, organic solvents, or by osmotic shock
Detergents : (SDS), Triton X-IOO,
Alkali : cell walls- saponification of lipids
Organic solvents: Toluene ruptures the cell wall by penetrating the cell wall lipids
Biological methods include Enzymatic digestion of the cell wall

10. PRODUCT ISOLATION
From the obtained Aqueous layer product is isolated or recovered
The different techniques used are –
Extraction
Precipitation
Adsorption

11. Solvent Extraction
It is a method used to separate compounds based on their relative solubilities in two different immiscible liquids
After the extraction, the solvent-rich phase is called the extract and the residual liquid from which solute has been removed is called the raffinate

12. Solvent Extraction
Ideal solvent should show –
mutual insolubility of the two liquid,
easy recoverability, a
nontoxicity

13. Precipitation
Formation of a solid in a solution during a chemical reaction
Solid formed is called the precipitate and the liquid remaining above the solid is called the supernate

14. Adsorption
Adsorption is the binding of molecules or particles to the surface
Conventional adsorption is a reversible
process as the result of intermolecular forces of attraction
Ion exchange resins are polymers that are capable of exchanging particular ions within the polymer with ions in a solution that is passed through them

15. Affinity adsorption is based on the chemical
interaction between a solute and a ligand which is attached to the surface of the carrier particle by covalent or ionic bonds
 ligand is an ion or molecule (see also: functional group) that binds to a central metal atom to form a coordination complex

16. PRODUCT PURIFICATION
After a product is recovered or isolated, it may need to be purified further.
The purification can be accomplished by numerous methods –
precipitation,
chromatography,
electrophoresis,
ultrafiltration

17. Chromatography
In this, separation of compound is based on liquid-liquid partitioning which takes place between static or stationary phase
Column Chromatography and Gel filtration chromatography

18. Electrophoresis
It is the separation of charged species based on their specific migration rates in an electrical field
When a mixture of solutes is placed in an electrical field, the positively charged species are attracted to the anode and the negatively charged ones to the cathode