Effects of Light Intensity on the Growth and Lipid Accumulation of Microalga <Emphasis Type="Italic">Scenedesmus</Emphasis> 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.