Astaxanthin extraction from Paracoccus carotinifaciens employing fatty acid based natural deep eutectic solvents

Astaxanthin is a red-orange pigment widely used as a natural dye, additive in animal feed (salmonids) and for human consumption as dietary supplements. Recently, the consumers’ demand for natural-based products has encouraged to exploit the high added value bioactive compounds obtained by biomass, for applications in food industry, was explored. Researchers made an effort to develop sustainable extraction processes to guarantee the biocompatibility and safety of the products. In the present work, the possibility of employing fatty acids based NaDES (Natural Deep Eutectic Solvents) as a non-toxic alternative to traditional hydroalcoholic solvents for the extraction of astaxanthin from Paracoccus Carotinifaciens was evaluated. Furthermore, the extraction kinetic was studied by using mass transfer and reaction kinetic models. In addition, the antioxidant activity of the extracts was evaluated at each extraction time by ABTS assay. Experimental results show that the extraction yield was up to 60% and the reaction kinetic model provided a slightly better fitting of the data, when compared to the mass transfer mode