Comparison of different methods for extraction of phycocyanin from cyanobacterium Arthrospira maxima (Spirulina)

Abstract

Abstract Phycocyanin is an interesting alternative for synthetic food colorants. For extraction of phycocyanin from representatives of cyanobacterial genus Arthrospira various methods have been described in literature including ultrasonication, glass bead extraction and freeze-thawing. In this work, three optimized methods for the extraction of phycocyanin from A. maxima were applied in order compare the effectiveness of the different processes. After harvesting the biomass, he extractions were carried out using ultrasonication followed by flocculation with chitosan in different organic acid solutions, glass bead extraction and freeze-thawing, both followed by centrifugation. The obtained extracts were analysed using spectrophotometry in the wavelength spectrum of 280 to 800 nm. The highest C-PC contents of 17.03 ± 0.53 % and 15.21 ± 0.41 % were achieved with the freeze-thawing and the ultrasonication method, respectively. The highest purity value of 2.02 ± 0.01 was achieved with ultrasonication and flocculation with chitosan in acetic acid. Using citric or lactic acid for flocculation with chitosan resulted in greenish extracts containing high amounts of chlorophyll. In conclusion, flocculation with chitosan in acetic acid can be an interesting alternative for centrifugation providing highly purified phycocyanin extracts.