Liquid-Liquid Extraction of Some Biomolecules in the ATPS {Ethyl Lactate (1) + Sodium Potassium Tartrate (2) + Water (3)} at 298.15 K and 0.1 MPa

Abstract

The mounting demandfor biomolecules in industry, particularlyin regard to antioxidant-rich food supplements and monoclonal antibodies,has been compelling pharmaceutical companies to invest in this fieldand to redesign the production of active pharmaceutical ingredients(APIs) by implementing the principles of green chemistry and circulareconomy. For example, by promoting the use of renewable feedstocks,such as biowaste from the food sector, it is possible to simultaneouslyavoid the footprint of chemical synthesis and reduce the price ofraw materials. Aqueous two-phase systems (ATPS), or aqueous biphasicsystems (ABS), have been gaining relevance in the extraction of biomoleculessuch as proteins, vitamins, and lipids, given their low price, lowenergy demand, large scale-up potential, and considerable biocompatibility.These features make ATPS very powerful primary concentration stepsin industrial processes, which become especially eco-friendly whencombined with green solvents such as ethyl lactate and salts of organicbasis. Among some common biomolecules in biowaste, cyanocobalamin(Cya), epicatechin (Epi), folic acid (Fol), and syringic acid (Syr)possess very interesting properties given their relatively large presenceand strong antioxidant potential. Therefore, in this work, these fourwell-known biomolecules were extracted in the ATPS {ethyl lactate(1) + sodium potassium tartrate (2) + water (3)} at 298.15 K and 0.1MPa. This eco-friendly ATPS allowed low mass losses (< 3 %) inthe liquid-liquid extractions, having attained the maximumpartition coefficients (K = 6.5 & PLUSMN; 0.4) and extractionefficiencies (E = 90.7 & PLUSMN; 0.2 %) for cyanocobalaminusing the longest tie-line (TLL = 70.73 m%). Conversely,for the same tie-line composition, the smallest performance indicators(K = 1.25 & PLUSMN; 0.03 and E = 69.3 & PLUSMN; 0.2 %) were obtained for folic acid. The partition studieswere performed after careful evaluation of the effect of pH on themean electrical charge of each biomolecule.