Storage, Processing, and Stability of Phycobilins

Phycobilins are a class of chromophores that are present in certain species of algae including cyanobacteria and red algae. These organisms exhibit a range of characteristic colors, from red to blue-green, which are attributed to the presence of highly efficient light-harvesting pigments. The three major phycobilins are phycocyanobilin (PCB), phycoerythrobilin (PEB), and phycurobilin (PUB). All of these pigments could absorb light within a particular region of the visible spectrum, thereby enabling living organisms to harness a broad range of light energy for the process of photosynthesis. Phycobilins exhibit physiological association with chlorophyll, which serves as the primary photosynthetic pigment in plants, albeit their chemical structure is distinct. Phycobiliproteins are specialized protein complexes that function as auxiliary pigments, collecting light and transferring it to chlorophyll molecules. They are composed of a linear tetrapyrrole chromophore that is explicitly linked to the protein complexes. The possession of phycobilins confers a competitive edge to these organisms in habitats with low light intensity, such as those found in deep water or shaded areas. These organisms are capable of assimilating and utilizing light energy, a feat that poses a challenge for certain photosynthetic organisms. This chapter is focused on extraction, storage, and processing of phycobilins for different biotechnological applications.