BIOREACTOR ► A stirred-tank reactor is usually cylindrical or with a curved base. ► The stirrer facilitates even mixing and oxygen availability throughout the bioreactor. ► Alternatively air can be bubbled through the reactor. ► Bioreactor also has an agitator system, an oxygen delivery system, a foam control system, a temperature control system, pH control system and sampling ports so that small ► volumes of the culture can be withdrawn periodically. ► Sparged stirred tank bioreactor through which sterile air bubbles are sparged. ► Small volume cultures cannot yield appreciable quantities of products. To produce in large quantities, the development of bioreactors, where large volumes (100-1000 litres) of culture can be processed, was required. ► A bioreactor provides the optimal conditions for achieving the desired product by providing optimum growth conditions.