Fig. 6

The effect of low temperature on promoting the conversion of LA to ALA. LA level (a) and ALA level (b) were determined in the control strain (WT D. salina) and transformants (including Ds-DsFADS6-9, Ds-DsFADS6-4, Ds-TpFADS6-8, and Ds-TpFADS6-10). Each alga was cultured in Ben-Amotz medium by supplementation with 500 mg/L MI, glucose/KNO₃ and 12% CO₂ aeration and conserved by 4 °C for 5 days. Optimization of culture temperature and time for each alga. LA level (c) and ALA level (d) were determined in the control strain (WT D. salina) and transformants (including Ds-DsFADS6-9, Ds-DsFADS6-4, Ds-TpFADS6-8, and Ds-TpFADS6-10) under 4, 8, 12, 16, and 26 °C (control) after 30-day cultivation for 5 days. After optimization of culture temperature, each transformant was cultured for another 5, 10, 15 or 20 days after 30-day growth under the optimal temperature. Each alga was cultured in Ben-Amotz medium by supplementation with 500 mg/L MI, glucose/KNO₃ and 12% CO₂ aeration. LA level (e) and ALA level (f) were determined in the control strain (WT D. salina) and transformants (including Ds-DsFADS6-9, Ds-DsFADS6-4, Ds-TpFADS6-8, and Ds-TpFADS6-10) under optimal temperature