Enhanced phycocyanin production from Spirulina subsalsa via freshwater and marine cultivation with optimized light source and temperature

To find out optimum and cost-efficient strategy for phycocyanin production, the effect of light source and temperature on Spirulina subsalsa growth were studied in chemically defined freshwater medium and seawater supplied with wastewater from glutamic acid fermentation tank. Maximum growth rate and the highest phycocyanin content were obtained by 35 degrees C and green light, respectively. A two-stage cultivation strategy was proposed and applied, which combines biomass accumulation at 35 degrees C and phycocyanin synthesis simulated under green light. As a result, phycocyanin production reached 70 mg/L/d and 11 mg/L/d from freshwater and seawater medium, respectively. With all tested conditions, a strong correlation between biomass and phycocy-anin/chlorophyll ratio, rather than phycocyanin, revealed the dependence of Spirulina subsalsa growth on coordinating regulation of photosynthetic pigments. The relationship between growth and phycocyanin pro-duction under various light and temperature can be a good basis for improving phycocyanin production from Spirulina subsalsa with or without freshwater consumption.

Automated summary

To determine the best strategy to produce phycocyanin in a cost-efficient way, the impact of light source and temperature on the growth of Spirulina subsalsa was examined. The results revealed that the highest growth rate was achieved at 35 degrees C, while the highest phycocyanin content was obtained under green light. Furthermore, a two-stage cultivation strategy combining biomass accumulation at 35 degrees C and phycocyanin synthesis under green light was proposed and implemented, resulting in significant phycocyanin production.