For the first time, a mixed photosynthetic culture (MPC) consisting of a consortium of bacteria and algae
was investigated for its capacity to accumulate polyhydroxyalkanoates (PHA). The culture was subjected
to a feast and famine regime in an illuminated environment without supplying oxygen or any other electron acceptor. The MPC accumulated PHA during the feast phase and consumed it in the famine phase,
where the PHA consumption was made possible due to oxygen production by algae The internal cycling
of carbohydrates was also observed, which was likely linked to bacterial glycogen being used as an additional source of energy for acetate uptake during the feast phase, and restored in the famine phase via
PHA degradation The MPC reached a PHA content of 20%, with a PHA storage yield per acetate similar
to aerobic systems, opening up the possibility of a new sunlight-driven PHA production process without
the need for aeration.