Effects of nitrogen source and concentration on biomass and oil production of a Scenedesmus rubescens like microalga.
This investigation examined the effects of nitrogen source and concentration on the ash free dry biomass (AFDB) and oil accumulation and productivity of a Scenedesmusrubescens like alga cultivated in indoor photo-bioreactors and outdoor raceway ponds. Among the nitrogen sources ((NH4)2CO3, urea, NaNO3, urea and NaNO3 mixture), the algae fed with the mixture of urea-N and NaNO3-N had the highest AFDB productivity of 0.539±0.040 g/L/d and the content of fatty acid methyl esters (FAME) (%) fed with (NH4)2CO3-N increased continuously for 17 days and reached 42.94±2.05% in the indoor photo-bioreactors. The content of C18 series (as % of total FAME) was high in all the treatments of nitrogen sources. The algae fed with (NH4)2CO3-N had the highest FAME productivity of 0.133 g/L/d (P<0.001). The effect of ammonia concentration on the AFDB and FAME productivity was also studied during the 20-day cultivation in the outdoor raceway cultivation system. The mean FAME of the algae cultivated in the ammonia concentration of 1.0-1.5 mg/L were the highest (0.556±0.112 g/m2/d) (P<0.001). The total Kjeldahl nitrogen (TKN) in the algae and cultivation water decreased but the FAME content (%) of the algae increased during the nitrogen starvation phase.
Lin
Qiang
Q
Key Laboratory of Marine Bio-resource Sustainable Utilization and Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, PR China. linqiangzsu@163.com
Lin
Junda
J
D000641:Ammonia / Q000378:metabolism; D018533:Biomass; D004952:Esters / Q000378:metabolism; D005227:Fatty Acids / Q000032:analysis; D058086:Microalgae / Q000187:drug effects / Q000254:growth & development*; D009584:Nitrogen / Q000378:metabolism / Q000494:pharmacology*; D009821:Oils / Q000138:chemical synthesis*; D044444:Scenedesmus / Q000187:drug effects / Q000254:growth & development*
D004952:Esters; D005227:Fatty Acids; D009821:Oils; D000641:Ammonia; D009584:Nitrogen