In order to determine the impact of nitrogen deficiency in medium, growth rate and carotenoids contents were followed during 15 days in two strain Dunaliella spp. （DUN2 and DUN3）, isolated respectively from Azla and...In order to determine the impact of nitrogen deficiency in medium, growth rate and carotenoids contents were followed during 15 days in two strain Dunaliella spp. （DUN2 and DUN3）, isolated respectively from Azla and Idao Iaaza saltworks in the Essaouira region （Morocco）. These microalgae were incubated at 25 ± 1 ℃ with a salinity of 35960 and continuous light in four growth media with different concentrations of sodium nitrate （NaNO3）： 18.75 g/L, 2.5 g/L, 37.5 g/L and 75 g/L. Maximum of cell density was observed under high sodium nitrate concentration during logarithmic phase of growth. The highest specific growth rate was 0.450 × 10^6 ± 0.006 cells/mL and 2.680 × 10^6 ± 0.216 cells/mL, respectively for DUN2 and DUN3. Carotenoids production mean were not stimulated under nitrogen deficiency, and the highest content was showed in DUN2 at high nitrogen concentration （3.210 ± 0.261 μg·mL^-1） compared with DUN3 strain.展开更多
文摘In order to determine the impact of nitrogen deficiency in medium, growth rate and carotenoids contents were followed during 15 days in two strain Dunaliella spp. （DUN2 and DUN3）, isolated respectively from Azla and Idao Iaaza saltworks in the Essaouira region （Morocco）. These microalgae were incubated at 25 ± 1 ℃ with a salinity of 35960 and continuous light in four growth media with different concentrations of sodium nitrate （NaNO3）： 18.75 g/L, 2.5 g/L, 37.5 g/L and 75 g/L. Maximum of cell density was observed under high sodium nitrate concentration during logarithmic phase of growth. The highest specific growth rate was 0.450 × 10^6 ± 0.006 cells/mL and 2.680 × 10^6 ± 0.216 cells/mL, respectively for DUN2 and DUN3. Carotenoids production mean were not stimulated under nitrogen deficiency, and the highest content was showed in DUN2 at high nitrogen concentration （3.210 ± 0.261 μg·mL^-1） compared with DUN3 strain.
