Carotenoids are pigments produced by plants and algae and play a role in light harvesting as part of the photosynthesis process.

[1] It is an accessory pigment found in the chloroplasts of many brown macroalgae, such as Fucus spp., and the golden-brown unicellular microalgae, the diatoms.

[3] In diatoms like Phaeodactylum tricornutum, fucoxanthin is protein-bound along with chlorophyll to form a light harvesting protein complex.

[6] Fucoxanthin is present in brown seaweeds and diatoms and was first isolated from Fucus, Dictyota, and Laminaria by Willstätter and Page in 1914.

[7] Seaweeds are commonly consumed in south-east Asia and certain countries in Europe, while diatoms are single-cell planktonic microalgae characterized by a golden-brown color, due to their high content of fucoxanthin.