Screening of Isochrysis strains for simultaneous production of docosahexaenoic acid and fucoxanthin

Microalgae are capable of synthesizing a wide range of value-added compounds such as docosahexaenoic acid (DHA) and fucoxanthin. In the present study, the potential for simultaneous production of DHA and fucoxanthin by the marine alga Isochrysis was investigated via strain screening and culture optimization. A comparative analysis of sixteen Isochrysis strains revealed that CCMP1324 was superior with regard to growth and production of DHA and fucoxanthin. In response to various nutritional and environmental cues, CCMP1324 accumulated DHA and fucoxanthin in a coordinated and growth-dependent manner, which reached similar to 17.1 and 14.1 mg g(-1), respectively. A semi-continuous culture strategy leading to high productivities of DHA (9.05 mg L-1 day(-1)) and fucoxanthin (7.96 mg L-1 day(-1)) was developed. Taken together, our study represents a pioneering work studying the accumulation coordination between DHA and fucoxanthin in Isochrysis. These findings provide valuable insights into future exploration for the integrated production of high-value compounds.