Light emitting diodes as alternative light source for growth and carotenoid enhancement in Chlorococcum humicola Cultured in airlift photobioreactors.

This study compares the performance of white light emitting diodes (LEDs) and fluorescent lamps for cultivating Chlorococcum humicola (C. humicola) as aquaculture feed. Results demonstrate that daylight LEDs are seen to yield the highest biomass concentration at 1,010 ± 11 mg/L, exceeding fluorescent lamps by 36 %. Switching to daylight LEDs increased carotenoid content in algal biomass from 2.97 ± 0.23 to 3.86 ± 0.15 mg/g and carotenoid concentration from 2.21 ± 0.16 to 3.90 ± 0.27 mg/L: increases of 36 % and 76 %, respectively. Blue and daylight LEDs proved to be most effective for lutein induction, with less impact on beta-carotene. Biomass under daylight LEDs shows promising values for protein and lipid contents of 32 % and 11 % dry weight, respectively. Daylight LEDs consumed less than half the energy of fluorescent lamps. Daylight LEDs significantly enhance the growth and carotenoid content of C. humicola, offering a sustainable alternative for aquaculture feed production.