Table 2. Fatty acid results.
The concentrations (µg in mg dry weight) of 16:0 fatty acid (FA), alpha-linolenic acid (ALA; 18:3ω3), stearidonic acid (SDA; 18:4ω3), eicosapentaenoic acid (EPA; 20:5ω3), docosahexaenoic acid (DHA; 22:6ω3), total omega-3 (ω-3) FAs and total FAs in M. kalinae, Cryptomonas sp. and C. ozolinii in autotrophic controls and when grown osmotrophically with different glucose (i.e., 0.5 mg L−1, 2 mg L−1, 5 mg L−1) and leucine (20 mg L−1, 100 mg L−1, 400 mg L−1) concentrations in the long-term experiment. Replication n = 3. Standard deviations are given in parenthesis. Different letters (a, b, c) denote significant differences (Tukey’s HSD p < 0.05) between treatments, only statistically significant results are indicated.
| Strain | Fatty acid | Control | Glucose 0.5 | Glucose 2 | Glucose 5 | Leucine 20 | Leucine 100 | Leucine 400 |
|---|---|---|---|---|---|---|---|---|
| Mallomonas kalinae | 16:0 | 8.2 (2.3) | 4.1 (0.1) | 7.9 (1.5) | 5.0 (1.9) | 8.1 (1.0) | 4.0 (0.1) | 6.8 (1.9) |
| ALA | 7.3 (0.0)a | 6.7 (4.1)ab | 8.3 (0.0)b | 4.8 (4.7)abc | 10.9 (1.1)b | 4.6 (0.3)c | 8.0 (1.1)ab | |
| SDA | 10.3 (1.6)a | 8.3 (6.3)a | 9.0 (1.4)a | 6.2 (5.4)ab | 12.9 (1.2)a | 5.6 (0.4)b | 10.6 (3.9)ab | |
| EPA | 0.3 (0.0)a | 0.2 (0.1)ab | 0.3 (0.0)a | 0.2 (0.1)ab | 0.3 (0.0)a | 0.1 (0.0)b | 0.3 (0.0)a | |
| DHA | 0.8 (0.0) | 0.7 (0.5) | 0.8 (0.1) | 0.6 (0.3) | 1.0 (0.1) | 0.4 (0.0) | 0.7 (0.2) | |
| Total FA | 88.8 (5.8)a | 70.3 (8.7)ab | 74.1 (18.9)ab | 33.8 (14.8)bc | 63.8 (27.9)ab | 45.6 (0.3)b | 56.8 (22.3)ab | |
| Cryptomonas sp. | 16:0 | 7.8 (1.0)ab | 7.8 (1.6)ab | 13.6 (0.4)b | 8.6 (0.7)ab | 10.4 (1.2)ab | 7.6 (2.0)ab | 10.2 (0.3)a |
| ALA | 21.7 (3.7)ab | 16.8 (2.3)ab | 23.2 (0.3)a | 18.9 (3.2)ab | 20.1 (0.9)ab | 17.1 (1.2)ab | 18.0 (0.2)b | |
| SDA | 11.5 (2.2) | 14.9 (1.3) | 17.1 (2.6) | 15.1 (3.8) | 20.8 (2.2) | 13.3 (4.0) | 23.0 (1.2) | |
| EPA | 13.1 (2.1)a | 11.5 (0.5)ab | 13.6 (3.3)ab | 12.3 (2.7)ab | 14.9 (2.5)ab | 11.1 (3.0)ab | 16.8 (0.4)b | |
| DHA | 1.4 (0.0) | 2.0 (0.2) | 2.1 (0.6) | 1.8 (0.6) | 2.8 (0.3) | 1.7 (0.6) | 3.4 (0.2) | |
| Total FA | 60.7 (2.1) | 52.8 (16.5) | 73.6 (3.1) | 70.5 (15.6) | 67.7 (16.2) | 55.9 (7.8) | 68.8 (26.1) | |
| Cryptomonas ozolinii | 16:0 | 4.3 (0.0) | 5.2 (1.5) | 4.8 (1.5) | 4.6 (0.2) | 5.3 (1.0) | 4.5 (0.2) | 5.0 (0.1) |
| ALA | 8.1 (1.3) | 10.1 (3.6) | 9.5 (4.1) | 9.0 (0.8) | 10.9 (2.1) | 9.2 (0.5) | 8.5 (2.8) | |
| SDA | 8.5 (0.2) | 11.7 (4.2) | 10.9 (6.1) | 11.1 (0.8) | 13.6 (1.7) | 11.5 (1.2) | 10.0 (3.7) | |
| EPA | 7.0 (2.6)a | 8.9 (2.8)ab | 8.5 (4.5)ab | 9.1 (1.8)ab | 11.1 (0.1)b | 9.7 (1.6)ab | 8.2 (2.5)ab | |
| DHA | 1.6 (0.0)a | 2.2 (0.7)ab | 2.0 (1.2)ab | 2.4 (0.7)ab | 2.8 (0.0)b | 2.6 (0.5)ab | 2.0 (0.7)ab | |
| Total FA | 35.9 (7.1) | 35.2 (0.3) | 44.8 (18.0) | 37.1 (4.6) | 45.1 (16.9) | 43.0 (9.6) | 32.9 (2.8) |