Artificial light source selection in seaweed production: growth of seaweed and biosynthesis of photosynthetic pigments and soluble protein.

Seaweed growth is often limited by light. Artificial light supply has been well studied in terrestrial agriculture, however, much less is known about its effect in seaweed aquaculture. In this study, the effects of four artificial light sources (white, red, green, and blue LEDs light) on a brown alga and a green alga were investigated Seaweed growth, accumulation of photosynthetic pigments (chlorophyll and carotenoid), and soluble protein were evaluated. White LED light was the optimal supplementary light when cultivating and , because it promoted seaweed growth while maintaining protein production. Meanwhile, red LED was unfavored in the cultivation of , as it affected the seaweed growth and has a lower residual energy ratio underneath the water. LEDs would be a promising supplementary light source for seaweed cultivation.