Effects of light intensity on the growth and lipid accumulation of microalga Scenedesmus sp. 11-1 under nitrogen limitation.

Scenedesmus spp. have been reported as potential microalgal species used for the lipid production. This study investigated the effects of light intensity (at three levels: 50, 250, and 400 μmol photons m(-2) s(-1)) on the growth and lipid production of Scenedesmus sp. 11-1 under N-limited condition. Carotenoid to chlorophyll ratio was higher when algae 11-1 grew under 250 and 400 μmol photons m(-2) s(-1) than that under 50 μmol photons m(-2) s(-1), while protein contents was lower. Highest biomass yield (3.88 g L(-1)), lipid content (41.1 %), and neutral lipid content (32.9 %) were achieved when algae 11-1 grew at 400 μmol photons m(-2) s(-1). Lipid production was slight lower at 250 μmol photons m(-2) s(-1) level compared to 400 μmol photons m(-2) s(-1). The major fatty acids in the neutral lipid of 11-1 were oleic acid (43-52 %), palmitic acid (24-27 %), and linoleic acid (7-11 %). In addition, polyunsaturated fatty acids had a positive correlation with total lipid production, and monounsaturated fatty acids had a negative one.