Phaeodactylum tricornutum as a potential feedstock for an integrated biorefinery process under varying cultivation conditions

In this study, the effects of temperature, light intensity, and aeration rate on the biomass, total lipid, and the residual water-soluble fractions of Phaeodactylum tricornutum were ascertained. The maximum total lipid yield of 22.39% was attained at a n-hexane/biomass ratio of 200/1, Soxhlet extraction time of 6 h and a heating rate level of 6 at 69 degrees C. The optimum fatty acid composition with a mass fraction of 99.70% was detected at a temperature of 10 degrees C, a light intensity of 431 mu mol m-2 s-1, and an aeration rate of 3.0 L min-1. The total fatty acid consisted of a major percentage of MUFAs (46.1-56.6%), followed by SFAs (39.5-53.2%), and PUFAs (0-12.5%) pro-viding a CN index of 59.3, IV of 70 g I2/100 g FAMEs, DU of 71%, CFPP of -4.5 degrees C, and SV and HHV of 205 mg KOH g-1 and 39.5 MJ kg-1, respectively, meeting the requirements of EN 14214 and ASTM D6751. Additionally, the maximum total phenol content value of 3.53 mg Gallic acid equivalent g-1 dry weight was obtained via a Folin-Ciocalteu assay at 22 degrees C, 98 mu mol m-2s-1, and 3.0 L min-1, while, the maximum total antioxidant capacity of 16.27 mu mol Trolox equivalent an-tioxidant capacity g-1 dry weight was observed with the help of the ABTS method over a broader cultivation condition range. Hence, P. tricornutum can be considered as a potential feedstock for biofuel and value-added bioproduct production offering a novel integrated lab-scale biorafina-tion process.