Taguchi’s design for optimization of phycocyanin extraction from Arthrospira (Spirulina) platensis

Abstract

Blue-green microalgae are the source of many commercially important products such as protein, amino acids, fatty acids, carotenoids and phycobiliproteins, and biotechnological studies on this issue has been profoundly increasing. Arthrospira (Spirulina) platensis is the main source of cyanobacterial phycocyanin, used as a natural colorant that is called as "Lina blue" in the commercial area. The purity ratio and quantity of phycocyanin may vary depending on the processing method, also the purity of the phycocyanin is an important factor that determines its application area. Food-grade phycocyanin is utilized safely as a natural dye in the food formulation without offering health risk. Many conventional methods are used in several to obtain crude extracts of C-PC, such as freezing and thawing, sonication and mechanical disruption. Also, for the purification stage high-speed centrifugation, precipitation with ammonium sulphate, and ion-exchange chromatography methods are used. The aim of this study is to investigate the effects of a modified and combined extraction and purification method, including precipitation, chilling and centrifugation, at different centrifuge speeds, temperature and time on phycocyanin concentration to obtain a food grade phycocyanin from Spirulina platensis. As a result, centrifugation at 25 °C was found the higher purity ratio, above 0.7.