Effect of salinity on growth, biochemical composition, and lipid productivity of <i><scp>N</scp>annochloropsis oculata</i><scp>CS</scp> 179

Abstract

Effect of salinity (15, 25, 35, 45, and 55‰) on growth, biochemical composition, and lipid productivity of N annochloropsis oculata CS 179 was investigated under controlled cultivation in a 19‐day study. The results demonstrate that the dry biomass of N . oculata was the highest at a salinity of 25‰ among the treatments in the first 10‐day cultivation ( P &lt;0.05). During days 14–19 (stage III), the dry biomass productivity was the highest at a salinity of 35‰ ( P &lt;0.05). The algae had the highest chlorophyll a content (26.47 mg g −1 ) at 25‰ in stage I, and it decreased continuously at stage III. Protein content (as% of dry biomass) of algae reached the highest value of 42.25 ± 2.10% at 15‰, and the lipid content was the highest of 32.11 ± 1.30% of dry biomass at 25‰. However, the lipid productivity of these algae was the highest at 35‰ (64.71 mg L −1 d −1 ; P &lt;0.001). C 16 series content was the highest among the total fatty acid methyl esters ( FAME ), and eicosapentaenoic acid C 20:5n‐3 ( EPA ) content was high at the low salinity. Fatty acid profiles of N . oculata varied significantly under different salinities.