(214e) Enhanced Wet Extraction of DHA Using Room-Temperature Ionic Liquids

Polyunsaturated Fatty Acids (PUFAs), especially omega-3 fatty acids such as docosahexaenoic acid (DHA), are significant in modulation and prevention of various diseases. Therefore increasing attentions to PUFAs extraction are paid for biotechnological industries. Marine fish are still the major but not sustainable source of PUFAs due to the growing demand. Thraustochytrids, as heterotrophic microalgae, have been targeted for alternative source because of the robust growth rates and high docosahexaenoic acid (DHA). Recently, ionic liquids (ILs) have been extensively investigated to improve the efficiency of solvent extraction of lipids from microalgae and yeast. Moreover, ILs allow lipid extraction from wet biomass at ambient temperatures in less time than traditional extraction methods. This work aimed to study PUFAs extraction from Thraustochytrium sp. (T18) under pretreatment of the phosphonium-based IL (tetrabutylphosphonium propanoate [P₄₄₄₄][Prop]). The promising ionic liquid was first demonstrated to be applied in this microalgae via gravimetric analysis of total extractable oils. The resultant oil extracted after IL pretreatment was ulteriorly characterized with respect to fatty acid methyl ester (FAME) composition. The effect of process parameters were investigated for the ionic liquid, for instance the ratio of ionic liquid to co-solvent, the mass ratio of algae to the mixture of ionic liquid and co-solvent. The results indicate that the ionic liquid possesses the ability to disrupt the cells of Thraustochytrium sp. by itself and allow a facile recovery of oils over a large degree of wet microalgae (77.2 wt % water) in a short time at room temperature, providing the exploitation of a water compatible, energy saveable, PUFAs production process.