Mémoire
| Résumé : | Nitrogen is principally considered as one of the fundamental nutrients for algal cells, which directly affecting growth and biochemical compositions of marine microalgae. Thus, the focus of this study was to compare the growth and proximate compositions of Tetraselmis chuii cultured in different NaNO3 and urea concentrations. Results showed that T. chuii cultivated in 82.5 mg L-1 nitrogen (N) concentration of NaNO3 had significantly (p < 0.05) higher growth in terms of cell density (3.0 × 106 cells mL-1), dry biomass (0.0140 g L-1) and optical density (0.205) compared to 4.1 mg L-1, 8.25 mg L-1, 16.5 mg L-1and 33.0 mg L-1 N, respectively. On the other hand, T. chuii cultured in urea at 93.4 mg L-1 N had significantly (p < 0.05) higher growth in terms of cell density (3.33 × 106 cells mL-1), dry biomass (0.0145 g L-1) and optical density (0.205) compared to 11.67 mg L-1, 23.35 mg L-1, 46.7 mg L-1, and 233.5 mg L-1 N, respectively. Further, significantly (p < 0.05) higher protein content (45.24% dry weight) had found for urea at 233.5 mg L-1 N concentration compared to all other concentrations of NaNO3. In contrast, significantly (p < 0.05) higher carbohydrate content was found at 4.1 mg L-1 N (29.76% dry weight) and 11.67 mg L-1 N (28.03% dry weight) respectively, compared to other concentrations of NaNO3 and urea. Therefore, the present study revealed that increasing or decreasing concentrations of nitrogen had a significant effect on the growth and proximate composition of T. chuii. |
