Enhanced production of eicosapentaenoic acid and fucoxanthin in Phaeodactylum tricornutum via a two-stage strategy with multifactorial synergistic effects
摘要
Eicosapentaenoic acid (EPA) and fucoxanthin are two bioactive compounds widely present in marine microalgae, recognized for their significant economic value. However, their practical applications are constrained by low natural content and high production costs. To address these challenges, this study investigates the productivity of EPA and fucoxanthin in the diatom Phaeodactylum tricornutum under various environmental and chemical factors, aiming to enhance the production efficiency of both compounds simultaneously. A two-step cultivation strategy was employed. Initially, P. tricornutum was cultured under conventional conditions (20 ± 1℃, 100 μmol photons·m−2·s−1) to promote biomass accumulation. From day 7, culture conditions were modified to explore the effects of different temperatures (20 and 12 °C), light intensities (100 and 130 μmol photons m−2 s−1), and the presence or absence of the plant hormone methyl jasmonate (MJ) on the production of EPA and fucoxanthin. The results demonstrated that the combined treatment of low temperature (12 °C), high light intensity (130 μmol photons m−2 s−1), and MJ (2.5 mg L−1) significantly enhanced the production of both EPA and fucoxanthin. The highest EPA productivity reached 1.68 mg L−1 day−1, representing a 533.04% increase compared to the control. Similarly, the maximum fucoxanthin productivity was 0.42 mg L−1 day−1, a 152.36% improvement over the control. These findings provide a scientific basis for the future commercial-scale production of EPA and fucoxanthin.