Importance of bacterial storage polymers in bioprocesses

In waste water treatment processes microorganisms are subjected to a feast and famine regime. For sequencing batch processes this is often even more pronounced. Based on literature reports and own research it is hypothesized that in general microorganisms respond to these feast-famine regimes by accumulating storage polymers (polyhydroxyalkanoates) when substrate is present. The storage polymers are used for growth when the external substrate is depleted. In this manner the organisms are capable to balance their growth. A general hypothesis explaining polymer formation is developed. The advantages and disadvantages of this formation of storage polymers for the operation of SBR processes is discussed.