Comparison of the biochemical composition of different Arthrospira platensis strains from Algeria, Chad and the USA

Arthrospira platensis (Spirulina) is a widely known microalga with nutritional and therapeutic applications due to its richness in nutrients and bioactive elements. The aim of this research was to characterize the phytochemical and nutritional compounds of five different Spirulina strains from the USA, Chad and Algeria. Concentrations of carbohydrates and fats, fatty acid profile, and the total proteins were determined through biochemical and chromatographic methods. The concentration of phytochemical compounds was determined by using UV–Vis spectrophotometry. The Spirulina from the USA had the highest amounts of lipids, proteins, phycocyanin and chlorophyll a content compared to the others strains tested. The strains from Algeria had the highest amount of carotenoids (5.50 mg/g) among the strains investigated. In all the strains, the main fatty acid compound was the palmitic acid (16:0) with the highest concentration of 71.15% in the Spirulina from Chad. All the Spirulina strains tested contained high quantities of ω-6-fatty acids (avg. 24%) except in the Spirulina strain from Chad, which had only 10.59%. All the Spirulina strains investigated were rich in polyphenols with the highest value of 67.52 mg GAE/g in the strains from Algeria. The Spirulina from the USA has more potential to be used in the nutraceutical and a functional food area since it is very rich in bioactive compounds.