Storage Stability of Spirulina Extract Extracted with Natural Eutectic Solvent

Abstract

In this study, functional substances from Spirulina were extracted using deep eutectic solvent (DES) synthesized with cosmetic ingredients as a new natural extractant, In order to investigate the possibility of replacing water and ethanol, which are common extraction solvents, 9 kinds of DESs were synthesized. 3 DESs with low cytotoxicity were selected to extract functional substances from Spirulina. the contents of polyphenols, phycocyanin and ABTS radical scavenging ability of the Spirulina extract were measured to study the antioxidant activity. The polyphenol and phycocyanin contents of the Spirulina extract were highest when extracted with water. However, the antioxidant activity of the Spirulina extract prepared with sodium acetate: glycerol (SA: Gly) was 4 and 4.5-folds higher than those of the extract prepared with water and 70% ethanol, respectivly. The ability of DESs as preservatives for functional materials of Spirulina extract was also investigated. The polyphenols and phycocyanin of all DES extracts were more stably preserved than those in 70% ethanol or water. The antioxidant activity of Spirulina extract in sodium acetate:glycerol (1:3) was maintained over 60% after 9 days storage, while only 10% of initial activity was retained in 70% ethanol. These results show the potential of DESs as both extraction solvents and preservatives for functional substances from Spirulina.