Photobioreactor systems for production of astaxanthin from microalgae

Astaxanthin, which has a strong antioxidant ability, is steadily increasing in demand in the nutraceutical and pharmaceutical industries because of its ability to effectively treat various diseases. In particular, microalgae-derived astaxanthin has excellent efficacy and can be produced through direct conversion of CO2, making it sustainable. However, low productivity, contamination vulnerability, and the processing complexity of microalgae prevent large-scale commercialization. Accordingly, various technologies including strain development, culture mode selection, contamination control, and extraction have been developed to improve production efficiency in all process steps, from upstream to downstream processes. Among them, this study investigated the structure of various photobioreactor (PBR) systems and compared the productivity of astaxanthin in each system. Moreover, it analyzed how the change in the culture environment conditions caused by the PBR system affected the physiological activity of cells and astaxanthin production. Consequently, these analysis results can contribute to a PBR system design that is more advantageous for efficient astaxanthin production. In addition to the astaxanthin-producing microalgal strains identified so far, the identification of other astaxanthin-rich microalgal species will aid the development of a PBR system suitable for the characteristics of the strain.