ABSTRACT
Major differences exist between the variable parameters available for control in batch and continuous culture. When microorganisms are grown in batch culture their environment is in continual flux. In batch culture, in the absence of an inhibitor, growth ceases through lack of one or more essential nutrients. Bacterial growth occurs at a constant rate in a fixed physico-chemical environment and can be controlled by the input of medium. Nutrient concentration, pH, metabolic products, and oxygen tension, all of which change during batch culture, can be maintained at a steady state in continuous culture, while controlling the growth rate, up to the maximum, for the chosen medium. Nutrient limitation of growth rate in batch cultures is only short lived, since substrate concentrations are constantly changed by consumption of nutrient. The biomass in the culture will decrease, as for magnesium and iron as substrates, as an inverse function of dilution rate.
