Protein pigment complexes
Phycocyanin is a pigment-binding protein from the phycobiliprotein family that is used in food, pharmaceutical, and cosmetic preparations. There are two types of phycocyanin—characteried as C-phycocyanin and R-phycocyanin—that are derived from green and red algae, respectively.2 In algae, phycocyanin serves the role of a light harvesting complex. Its primary use in cosmetics is as a colorant due to its pigment characteristics. In the nutrional supplement industry, spirulina has become a popular due to its high levels of protein. Spirulina comes from the algae, Arthrospira plantensis, which produces C-phycocyanin. Spirulina is reported to have antioxidant properties and also purported as a beneficial agent for cardiovascular health.