Differences between continuous and fed-batch

CONTINUOUS:

1. Nutrient addition - Continuously or intermediary with corresponding withdrawal of same volume of media.
2. Type of system - Open system
3. Growth state - Steady state is maintained
4.  specific growth rate = dilution rate 
5. Cell maintenance - It is in log phase.
6. Application - primary metabolites cannot be used for secondary metabolites.
7. catabolite repression - cannot overcome.
8. Types - chemostat, turbidostatic.

FED-BATCH:

1. Nutrient addition - No withdrawal but nutrients or precursors are added without harvesting the medium 
2. Type of system - Partially closed
3. Growth state - A Quasi (pseudo) state is maintained
4.  specific growth rate may not be equal to dilution rate 
5. Cell maintenance - Not necessarily in log phase.
6. Application - Can be used for both primary metabolites and secondary metabolites.
7. catabolite repression - can be overcome.
8. Types - Fixed, variable cyclic