Abstract
Arthrospira platensis is a cyanobacterium known for its widespread use as nutraceutical and food additive. Besides a high protein content, this microorganism is also endowed with several bioactivities related to health benefits in humans that make it a candidate for functional foods. These properties are strain and culture condition dependent. We compared, in terms of biomass productivity and protein, C-phycocyanin, and polysaccharide content, two A. platensis strains, A. platensis F&M-C256 and A. platensis F&M-C260, characterized by morphological differences. The organisms were grown in annular photobioreactors with light-emitting diodes (LED) as light source in fed-batch and semi-continuous regimes. No significant differences in biomass productivity were found between the two strains. Both strains showed a protein content >55% in all culture conditions. C-phycocyanin content was higher in A. platensis F&M-C260 in semi-continuous regime. Cellular polysaccharide (PS) content, which included intracellular polysaccharide and those bound to the cell wall, was higher in A. platensis F&M-C256 during semi-continuous cultivation. In both strains, a higher release of polysaccharide was observed at the end of the fed-batch regime. A. platensis F&M-C256 showed the advantage to form clumps which facilitate harvesting, behavior not observed in A. platensis F&M-C260 and probably related to the different predominant monosaccharide found in the PS of the two strains (i.e., rhamnose in A. platensis F&M-C256 and glucose in A. platensis F&M-C260). The results show that the two strains are suitable for commercial production of high-value products, such as protein and C-phycocyanin, while for polysaccharide production, A. platensis F&M-C256 is preferable.
Highlights
Arthrospira platensis, commonly known as spirulina, represents one of the most important commercial cyanobacteria
Arthrospira is mostly cultivated in open ponds exploiting sunlight; it grows at high pH (>9) and bicarbonate concentration, which makes the culture medium rather selective (Belay 2013), some strains of A. maxima have been cultivated in seawater
Two strains of Arthrospira platensis were used in this study: A. platensis F&M-C256 and A. platensis F&M-C260, both obtained from the Microalgae and Cyanobacteria Culture Collection of Fotosintetica & Microbiologica S.r.l. (Florence, Italy)
Summary
Arthrospira platensis, commonly known as spirulina, represents one of the most important commercial cyanobacteria. Arthrospira is mostly cultivated in open ponds exploiting sunlight; it grows at high pH (>9) and bicarbonate concentration, which makes the culture medium rather selective (Belay 2013), some strains of A. maxima have been cultivated in seawater Artificial illumination in microalgal research and production was for long time attained with fluorescent tubes, which mimic natural radiation spectrum and include those wavelengths, such as green ( ≈ 520–560 nm) with low photosynthetic activity for certain microalgae (Schulze et al 2014); alternatively, LED can be used (Schulze et al 2014; McGee et al 2020). Several studies performed under artificial light with Arthrospira showed that quantity and quality of light play a key role in biomass productivity and composition (Wang et al 2007; da Fontoura et al 2020)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
