Biochemical Biomarkers in the Halophilic Nanophytoplankton: Dunaliella salina Isolated from the Saline of Sfax (Tunisia)

The purpose of the present work was to study the potential biotechnological use of Dunaliella species isolated from the solar saltern of Sfax (Tunisia). D. salina was grown in artificial seawater (3.4M NaCl) under a constant temperature (25°C) and light ( $${265 {\mu}{\rm mol} {\rm photons} {\rm m}^{-2} {\rm s}^{-1}}$$ ). The maximal cellular density was about $${4.66\times 10^{6} {\rm cells/ml}}$$ , and the growth rate ranged between 0.13 and 0.16 doublings/day. Chlorophyll a reached $${52.32 \pm 0.12 {\rm mg/l}}$$ in the exponential phase. Protein and carbohydrates content reached maximum values in the lag phase ( $${52.4 \pm 0.2}$$ and $${5.7 \pm 0.34\,{\rm mg/l}}$$ , respectively). The maximal values of total lipids content were obtained at the decline phase ( $${92 \pm 0.87\,{\rm mg/l}}$$ ). In addition, during this study, the analyses of the fatty acids profile have shown the presence of essential fatty acids that accumulate in D. salina during the stress phase.