Stirred-tank bioreactors have been designed for
(a) addition of preservatives of the product
(b) purification of the product
(c) ensuring anaerobic conditions in the culture vessel
(d) availability of oxygen throughout the process
(d) The most common type of aerobic bioreactor in use today is the stirred-tank reactor, which may feature a specific internal configuration designed to provide a specific circulation pattern. The stirred tank bioreactor have been designed for the availability of oxygen throughout the processes.