Impact of Different Storage Methods on Bioactive Compounds in Arthrospira platensis Biomass

Arthrospira platensis (spirulina) is considered a source of natural molecules with nutritionaland health benefits. As the dierent storage forms can aect the quantity and quality of bioactiveingredients, the aim of the present work was to evaluate the eects of freezing, oven-drying andfreeze-drying on chemical composition of spirulina biomass. Total proteins, photosynthetic pigmentsand antioxidants, were analyzed and compared to respective quantities in fresh biomass. The frozensample exhibited the highest content of phycocyanin-C, phenols, and ascorbic acid, also respect to thefresh biomass. The highest total flavonoid amount was in the freeze-dried biomass. HPLC-DADanalysis of phenolic acids revealed the presence of the isoflavone genistein, known for its therapeuticrole, in all the spirulina samples. The phosphomolybdenum method (TAC) and DPPH scavengingactivity were applied to determine the antioxidant activity of dierent samples. The highest DPPHscavenging activity was detected in fresh and freeze-dried biomass and it was positively relatedto carotenoid content. A positive correlation indicated that carotenoids, chlorophyll, ascorbic acidand all phenolic compounds were the major contributors to the TAC activity in spirulina biomass.The results highlighted a dierent functional value of spirulina biomass, depending on the processingmethods used for its storage.