Biomass and Pigment Production for Arthrospira platensis via
Semi-Continuous Cultivation in Photobioreactors: Temperature Effects
his study describes the response of Arthrospira platensis to a variety
of temperature conditions as reflected in variations of photosynthetic
parameters, pigmentation, and biomass productivity in indoor
photobioreactor (PBR) cultivations. These experiments are designed to
better understand the impact of temperature, seasonal variations, and
acclimation effects on outdoor biomass production. The irradiance levels
and temperature range (20 – 39°C) are chosen to enable modeling of
semi-continuous operation of large-scale outdoor PBR deployments.
Overall, the cultivations were quite stable with some pigment-related
instabilities after prolonged high temperature exposure. Changes in
productivity with temperature, as reflected in measured photosynthetic
parameters, are immediate and mainly attributable to the temperature
dependence of the photosaturation parameter, a secondary factor being
variation in pigment content. This study confirms that temperature is
critical for optimal performance of Arthospira platensis for both
biomass and pigment production and provides a basis for risk assessments
related to temperature mitigation for large-scale outdoor cultivations.
Finally, the biomass productivities in a semi-continuous operation mode
are quantitatively reproduced with a productivity model incorporating
the photosynthetic parameters measured herein. Those productivities are
in good agreement with extensive outdoor testing in PBR arrays at large
scale (24,000 L) and over long time periods (up to 18 months).