phycobilin

pigment

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July 23, 2026

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Phycobilins are a group of water-soluble pigments found in red algae and blue-green algae. They are derived from porphyrin, a complex cyclic structure composed of four pyrrole rings linked by methine groups. These pigments are crucial for photosynthesis, working alongside chlorophylls and carotenoids to absorb light energy across different wavelengths.12

Phycobilins appear as either blue (phycocyanobilin) or red (phycoerythrin) proteins. They are essential for algae to capture light energy that chlorophylls cannot absorb, thereby enhancing their photosynthetic efficiency. These pigments play a vital role in enabling algae to thrive in various light conditions.21

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blue-green algae
…yellowish carotenoids, the blue pigment phycobilin, and, in some species, the red pigment phycoerythrin. The combination of phycobilin and chlorophyll produces the characteristic blue-green colour from which these organisms derive their popular name. Because of the other pigments, however, many species are actually green, brown, yellow, black, or red.
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…yellowish carotenoids, the blue pigment phycobilin, and, in some species, the red pigment phycoerythrin. The combination of phycobilin and chlorophyll produces the characteristic blue-green colour from which these organisms derive their popular name. Because of the other pigments, however, many species are actually green, brown, yellow, black, or red.
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red algae
…a masking of chlorophyll by phycobilin pigments (phycoerythrin and phycocyanin). The reproductive bodies of red algae are nonmotile. The female sex organ, called a carpogonium, consists of a uninucleate region that functions as the egg and a trichogyne, or projection, to which male gametes become attached. The nonmotile male gametes…
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…a masking of chlorophyll by phycobilin pigments (phycoerythrin and phycocyanin). The reproductive bodies of red algae are nonmotile. The female sex organ, called a carpogonium, consists of a uninucleate region that functions as the egg and a trichogyne, or projection, to which male gametes become attached. The nonmotile male gametes…
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