Process optimization of fucoxanthin production with Tisochrysis lutea

Abstract

To optimize fucoxanthin production in Tisochrysis lutea, the effect of different process parameters on fucoxanthin productivity (Pfx) were evaluated using batch and continuous experiments. In batch, the highest Pfx was found at 30 °C and 300 μmol m^-2 s^-1, allowing to design continuous experiments to optimize the dilution rate. The highest ever reported Pfx (9.43-9.81 mg L^-1 d^-1) was achieved at dilution rates of 0.53 and 0.80 d^-1. Irradiance was varied (50-500 μmol m^-2 s^-1) to result in a range of absorbed light between 2.23 and 25.80 mol m^-2 d^-1 at a fixed dilution rate (0.53 d^-1). These experiments validated the hypothesis that light absorbed can be used to predict fucoxanthin content, resulting in 2.23 mol m^-2 d^-1 triggering the highest fucoxanthin content (16.39 mg/g). The highest Pfx was found with 18.38 mol m^-2 d^-1. These results can be used to achieve high Pfx or fucoxanthin content during cultivation of Tisochrysis lutea.

Keywords: Absorbed light; Dilution rate; Fucoxanthin; Temperature; Tisochrysis lutea.