First use of the WAVE™ disposable rocking bioreactor for enhanced bioproduct synthesis by N ₂-fixing cyanobacteria

WAVE™ rocking disposable bioreactors have been successfully utilized for bioproduct development from bacteria, yeast, microalgae, and animal and plant cells but not from cyanobacteria so far. N₂-fixing cyanobacteria represent a prolific bioproducts source with reduced cultivation costs. In this study, 1L cultures of the N₂-fixing cyanobacterium Anabaena siamensis grown diazotrophically in the WAVE™ bioreactor exhibited increased phosphate consumption and 37-70% higher CO₂ fixation rates than those grown in conventional bubbled suspension (BS) batch cultures. This generated 40-80% increased biomass productivities in the WAVE™ bioreactor reaching 60mgL^-1day^-1 when supplemented with 10% CO₂. Consequently, WAVE™ generated 36-153% more protein, lipid, and carbohydrate than BS, including 47-100% increased productivity of phycocyanin and stearidonic acid (SA) with relevant biomedical applications. While the type of culture system (BS or WAVE^TM) did not affect the biochemical profile of cyanobacterial biomass, 10% CO₂ supplementation induced a significant decrease in fatty acids and phycocyanin contents (mgg^-1DW). Therefore, for commercial applications, the CO₂ supplementation of WAVE™ should be optimized for each targeted bioproduct separately. This study opens possibilities for upgrading the WAVE™ systems to photobioreactors (PBRs) for bioproduct development from cyanobacteria, with opportunities and challenges critically evaluated herein. Biotechnol. Bioeng. 2015;112: 621-626.