Marine diatom Thalassiosira weissflogii based biorefinery for co-production of eicosapentaenoic acid and fucoxanthin

Diatom algae can produce bioactive compounds like fucoxanthin (FX) and ecosapentaenoic acid (EPA) which are of high demand in pharmaceutical and nutraceutical industries. Here, the influence of different light regimes in combination with major nutrients on growth, FX and EPA production by marine diatom Thalassiosira weissflogii were investigated. Batch cultures of T. weissflogii were illuminated under blue (BL), red (RL) and white (WL) light at two intensities. BL regime resulted in higher cell density with a specific growth rate of 2.49µ. Lipid productivity and lipid % as dry cell weight (DCW) was considerably higher in BL with EPA productivity of 33.4 mg L^-1d^-1. Fucoxanthin content as % DCW reached 0.95 (BL), 0.75 (RL) and 0.81 (WL) at mid exponential growth phase. The results further prove the plasticity of diatoms and provide a way for future metabolic engineering of T. weissflogii for potential microalgal bio-refinery for combined EPA and FX production.