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Equilibrium data were obtained for aqueous two-phase systems composed of ionic liquid (IL) and two inorganic salts (dibasic potassium phosphate, K2HPO4, and tripotassium phosphate, K3PO4) at 298.15 K. The evaluated ionic liquids were 1-butyl-3-methylimidazolium methanesulfonate ([C4mim][CH3SO3]), 1-butyl-3-methylimidazolium chloride ([C4mim][Cl]), and 1-ethyl-3-methylimidazolium chloride ([C2mim][Cl]). Equilibrium curves of salt and ionic liquid were determined. Additionally, each curve was fitted into three mathematical models. The aqueous two-phase system composed of the IL [C2mim][Cl] required a lower mass fraction of IL and salt to form the systems than the other two systems studied in this work containing [C4mim][Cl] and [C4mim][CH3SO3]. Furthermore, the type of inorganic salts studied did not affect the equilibrium curves for the same ionic liquid.

A green and sustainable method has been developed to extract anthocyanins from broken black rice (BBR) using aqueous solutions of poly(ethylene glycol) (PEG). The effects of time, PEG concentration, temperature, BBR mass, and PEG molar mass were investigated using multivariate experimental designs. Time and temperature were not significant in the studied range and PEG 1500 was the most suitable. Under the optimized conditions, the anthocyanin concentration was 130.7 mg 100 g−1. The stability of the extract was higher at 25 °C and pH 5.0, with a reduction in absorbance (λmax = 455 nm) of only 7.14% after 60 days. The extract was applied in a colorless soap, and the color remained stable for 60 days (greater reduction in absorbance of 15.5% at 40 °C, λmax = 497 nm), indicating its potential for direct application in products of industrial interest. The method was also effective to extract anthocyanins from the husk and bran of black rice, with concentrations of 148.1 and 883.2 mg 100 g−1, respectively. In comparison with conventional methods for extracting anthocyanins, the proposed new technique offers the advantages of efficiency, simplicity and low cost, with the difference in extract concentration being obtained with methanol acidified with HCl of only 11%.

The present study includes measurements of the phase composition, density, and refractive index of aqueous two-phase systems of poly(ethylene oxide) 1500 (PEO1500) + sodium thiosulfate + H2O at (28...

The phase compositions in liquid−liquid equilibria of aqueous two-phase systems (ATPS) composed of the poly(ethylene oxide)− poly(propylene oxide)−poly(ethylene oxide) (PEO−PPO−PEO) triblock copoly...

The partitioning of the whey protein lactoferrin, which is an iron transporter glycoprotein, in an aqueous two-phase system composed of poly(ethylene glycol) (PEG) and sodium citrate was evaluated. Equilibrium data at 25 °C were determined for each system studied using PEG with a molar mass of 1000 and 4000 g·mol1 at pH values of 5.5, 6.5, and 7.5. An increase in the molar mass of the polymer promoted the expansion of the two-phase region and caused the migration of the lactoferrin to the salt-rich bottom phase. An increase in pH also led to the expansion of the biphasic region. However, changing the pH over the tested range slightly affected protein partitioning. Lactoferrin recovery percentages greater than 94% were observed for all of the systems evaluated. The results indicated that lactoferrin can be successfully partitioned in an aqueous two-phase system formed of 14% (w/w) PEG and 10% (w/w) sodium citrate at pH 5.5 and 25 °C. The protein was concentrated 1000-fold in the salt-rich bottom phase in this system., Brazilian agencies FAPESB,CNPq, and FAPEMIG for their financial support