Effect of Light Wavelength on Biomass, Growth, Photosynthesis and Pigment Content of IEmiliania huxleyi/I

Light wavelength is a critical abiotic factor in modulating the development and pigment accumulation of microalgae. In the present study, we investigated the influences of white, red, blue, yellow, and green light on biomass (cell density), growth (cell diameter and dry weight), net photosynthetic rate, and pigment contents (chlorophyll a, fucoxanthin, and lutein) of the coccolithophore Emiliania huxleyi. The effects of light wavelength change on its cell density and fucoxanthin content were also evaluated. The results showed that blue light significantly stimulated the cell proliferation and photosynthetic activity of E. huxleyi. The cell diameter, dry weight, net photosynthetic rate, and the content of fucoxanthin under red light were significantly greater than under white light. E. huxleyi could not effectively utilize green light and yellow light for growth, photosynthesis, and pigment synthesis. Compared with white, blue, and red light, significantly greater cell density and fucoxanthin content were found under blue light, followed by red light. These findings indicated that light wavelength could significantly affect the growth, photosynthesis, and pigments of E. huxleyi. The combination of blue and red light is likely to be an effective measure to enhance its biomass and fucoxanthin production.