Production of nutritionally active compounds from Spirulina platensis under various stress conditions

The free-floating, filamentous cyanobacteria Spirulina platensis is highly valued and in great demand worldwide for its high-value colors and phytonutrients. These compounds find use in health foods, feed, medicines, and diagnostics. The primary objective of this work was to enhance the growth of Spirulina under both oxidative and physiological stress conditions in order to maximize the synthesis of phycocyanin and carotenoid pigments. Cultures were subjected to different concentrations of hydrogen peroxide (H2O2) and sodium chloride for varying temperatures and pH levels. Under lower concentrations of H2O2 (4mM), the maximum carotenoid content was increased, but the phycocyanin content was found to be stimulated at 10mM. Moreover, the synthesis of both pigments was shown to be highest under physiological stress circumstances (40mM and 60mM NaCl concentration) and at an optimal pH of 8-9, helped by a temperature range of 25-30℃. The experimental results demonstrate that both carotenoid and phycocyanin exhibit antioxidant properties even in the presence of oxidative stress. This suggests that the aforementioned circumstances can be applied in future investigations to extract different antioxidants from S. platensis.