The role of light intensity in stimulating lutein production in Coelastrella saipanensis

Algae are particularly important since they synthesize various biomaterials of high commercial value, such as lipids, carbohydrates, amino acids, pigments, and carotenoids. One of the several carotenoids produced by microalgae, lutein is a critical pigment for the eye's retina, used as a dietary supplement and pigment for diet, cosmetic, and medicinal purposes. Most ecological parameters, including light, which is an essential growth regulator affecting the productivity of algal cells and the synthesis and distribution of their by-products under different qualities and intensities, greatly influence lutein production and accumulation in algae. In the present study, we investigated the effect of different light irradiance (120, 100, 80, 60, and 40 µmol/m2/s using white light-emitting diodes LEDs) on the increment of growth and lutein content in the algae Coelastrella saipanensis grown in Chu 10 media at a steady condition of 28°C and pH 7. The results of the present study revealed that light irradiance affects both growth efficiency and lutein content in the alga. The highest value of lutein was 0.562 µg/mg at 80 µmol/m2/s, while the lowest was 0.055 µg/mg at 120 µmol/m2/s. It can be concluded from this that C. saipanensis has a good production of lutein when exposed to appropriate light intensity, as these results are supported by statistical analyses at P ≤ 0.05.