*2.4. Pigments*

Macroalgae use light as energy source and pigments play a key role in gathering solar energy. These pigments absorb light from the visible spectrum [46,47]. Carotenoids are orange/red pigments that absorb light energy and then pass it on to chlorophyll, therefore playing a secondary role in photosynthesis [48]. Carotenoids supplement the light gathering potential of the algae. There is an alteration for both chlorophyll and carotenoid content in seaweeds depending on the ultraviolet radiation (UV) levels throughout the year. Both chlorophyll and carotenoid pigments possess antioxidant and chemo preventive properties [37,49]. The main algal pigments in commercial use at the present time comprise: beta-carotene, astaxanthin, lutein, phycocyanin, chlorophyll, and fucoxanthin.
