Evaluation of effective environmental parameters on lipid, protein and beta-carotene production in Spirulina platensis microalga

Effects of Light on the Growth and β-carotene Accumulation in the Green Algae Dunaliella salina

“…Most algae have light saturation points in the range of 26 -400 µmol photon/m 2 /s, although some strains of D. salina are able to adapt to extremely high light due to their good defense mechanism, for instance, some strains of D. salina showed the optimal growth at light intensities of more than 1000 µmol photon/m 2 /s [15]. The strain D. salina CCAP 19/30 was observed to decrease the photosynthesis rate when grown under illumination conditions of 200-500 µmol photon/m 2 /s due to photoinhibition, but at a higher intensity (1500 µmol photon/m 2 /s), when algae have synthesized intracellular glycerol to sTableilize and protect the photosynthetic apparatus, the rate of photosynthesis increased to the maximum [14].…”

“…High light intensity often stresses microalgae cells, inhibits photosynthesis, and directs the flow of carbon and energy to the synthesis of storage compounds rather than to protein synthesis [14]. However, the threshold for light stress depends on the species, strain, and cell composition characteristics.…”

“…Capa-Robles et al (2021) reported that a combination of 12.5 mM glycerol, 3.0 M salinity, and 50 μmol photons m −2 s −1 light intensity resulted in the best growth of 2.1 × 10 6 cell mL ) of the Mexican strain, D. salina BC02 [13]. In the study of Mohammadi et al (2023), the optimal condition for the growth of D. salina was at 3 molars salinity, pH higher than 7, nitrate concentration of 0.25 g/L, light intensity of 5000 lux, and temperature of 25 degrees Celsius, whereas the optimum β-carotene production occurred at a similar condition of these parameters but in a temperature of 30 degrees Celsius [14].…”