The Response of Bio-Component Production of Nannochloris oculata to the Combinations of Monochromatic Light

Illuminating conditions are crucial factors affecting the microalgal growth and biosynthesis. The effects of illuminating spectral quality on the growth and bio-component production of Nannochloris oculata were investigated. The results indicated that a high proportion of Red-light enhanced the pigments and carbohydrate production but reduced those of the biomass and lipid. Monochromatic Blue-light has advantageous effects on lipid production compared with Red- and White-light. The optimal light spectrum for the protein production was the combination of Red- and Blue-light at a ratio of 4:3 or 5:2. Among the seven fatty acids identified from N. oculata , the contents of C16:0, C18:0, and C18:3(n-3) in the lipid were inhibited by the increased proportion of Red-light while those of C18:2(n-9), C16:2(n-6), and C20:0 were inhibited by Blue-light. Monochromatic Red- and Blue-light and their combinations were proposed as a promising illuminating strategy for the large-scale cultivation aiming for various bio-components.