PHA production from wastewater by mixed microbial culture under short-term microbial enrichment

Abstract

In this research, the possibility of polyhydroxyalkanoates (PHAs) production in a mixed microbial culture fed by industrial soft drink wastewater was assessed. To enrich the microbial culture, an uncoupled carbon and nitrogen feeding strategy were used in sequencing batch bioreactor (SBR). To evaluate the efficiency of the strategy, PHA, substrate, dissolved oxygen, biomass and nitrogen concentration profiles were reported in the 16th cycles of the SBR. From the obtained data, COD and nitrogen removal efficiencies were 89 % and 75.5 %, respectively at the cycle time of 12h. Also, the maximum poly-hydroxybutyric acid (PHB) content and specific PHA production rate (qp) were achieved as 13.8% (mg-PHB/mg-TSS) and 6.4×10-3 (mg COD-PHA/mg COD-X.h), respectively.

Keywords

• PHA production
• Mixed culture
• Biomass enrichment
• Soft drink wastewater