The Effect of Optimum Photoperiod from Blue LED Light on Growth of Chlorella Vulgaris in Photobioreactor Tank

Abstract Study for investigated the optimum photoperiod from blue LED light for the growth of Chlorella vulgaris in culture tank. Photoperiods from blue LED Light (Light/Dark) were set up at 24:0, 16:8 and 12:12 h. The initial number of C. vulgaris cells was 1.6 x 105 ± 0.12 cells mL-1. Culture medium was using commercially available fertilizers. After 17 days of cultivation, the results showed that the 24:0 h photoperiod had better growth of algae than 16:8 and 12:12 h, with maximum number of cells of 1.64 x 107 ± 0.23 cells mL-1 specific growth rate (SGR) was 0.17 ± 0.05, -0.06 ± 0.11 and -0.19 ± 0.1% day-1 with statistically significant differences (P < 0.05) in day 5 of cultivation. The stationary phase continued up to day 3 of cultivation, between the treatment. The optimum temperature for growth ranged from 35.5–38.5°C. The results showed that blue LED lighting at 24:0 h is the optimum photoperiod for cultivation of C. vulgaris. Keywords: Photobioreactor tank, Photoperiod, Blue LED light, Chlorella vulgaris, Growth rate