Influence of Different Culture Selection Methods on Polyhydroxyalkanoate Production at Shortterm Biomass Enrichment

In this study, the potential of four different culture selection methods under shortterm enrichment time (STE) to accumulate PHAproducing bacteria in mixed activated sludge was compared and the most efficient culture selection method was introduced. This means, PHAproducing microbial community was firstly enriched in a sequencing batch bioreactor (SBR) with four different selection methods including an anaerobicaerobic process (SBR1), a fully aerobic batch process (SBR2), an uncoupled carbon and nitrogen feeding regime (SBR3) and aerobic/anoxic process (SBR4). In the next step, cellular PHA content was maximized in a fedbatch accumulator. From the obtained results, PHA could be accumulated up to 13.2, 10.8, 22.36, and 6 % (mgPHA/mgTSS) in SBR1, SBR2, SBR3, and SBR4, respectively. Uncoupled carbon and nitrogen feeding regime (SBR3) showed the best PHA accumulating ability when acetate was used as feed. Also, the SBR3 was fed by softdrink industrial wastewater to evaluate the capability of the selected strategy for treating real wastewater, which 13.75% of mgPHA/mgTSS was achieved.