Direct separation and purification of α‐lactalbumin from cow milk whey by aqueous two‐phase flotation of thermo‐sensitive polymer/phosphate

Abstract

BACKGROUND: ⊍-lactalbumin (⊍-La) is of great interest to the industry as a result of its excellent functional properties and nutritional value. Aqueous two-phase flotation (ATPF) of thermo-sensitive polymer poly (ethylene glycol-ran-propylene glycol) monobutyl ether (UCON) and KH 2 PO 4 was applied to directly separate and purify ⊍-La from milk whey, which was purposed to simplify the production process and reduced cost of production.RESULTS: The effect of ATPF composition and operating parameters on the flotation efficiency (E) and purity of ⊍-La were investigated. The optimal conditions included 2 min of premixing time, 30 mL min −1 flow velocity and 20 min of flotation time, whereas the composition conditions comprised 35.0 mL 0.18 g mL −1 phosphate solution (containing 10% (cow milk whey/salt solution, v/v) cow milk whey, 50 ppm defoamer and 2 g NaCl) and 5.0 mL of 40% (w/w) UCON solution. Under the optimal conditions, E of ⊍-La was 95.67 ± 1.04% and purity of ⊍-La was 98.78 ± 1.19%. UCON was recovered by a thermally-induced phase separation and reused in next ATPF process without reducing E of ⊍-La. Purified ⊍-La was characterized by several key technologies. The results indicated that ⊍-La in cow milk whey could be directly separated and purified by the ATPF and the purity was satisfactory. Moreover, it was suggested there was no obvious structure difference between the ⊍-La separated by ATPF and the ⊍-La standard.CONCLUSION: The present study enabled the recycling of UCON, providing an effective, economically viable and environmentally friendly approach for the separation and purification of protein.

Development of Antioxidant and Stable Conjugated Linoleic Acid Pickering Emulsion with Protein Nanofibers by Microwave-Assisted Self-Assembly

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pH-Stat Titration: A Rapid Assay for Enzymatic Degradability of Bio-Based Polymers

“…With the perspective of having sustainably produced, biocompatible, and biodegradable materials, the development of bioplastics especially from waste and renewable resources has become popular [3]. Advances in waste reutilization [4,5] and in the synthesis technology of biopolymers make it possible to convert agricultural and food waste into usable bio-based materials. Natural polymers like poly(lactic acid) (PLA), polyhydroxyalkanoate (PHA), and polyhydroxybutyrate (PHB) have been isolated through different processes from by-products of milk, sugar, biodiesel, and other industrial processes [3,6].…”

α-Cellulose Fibers of Paper-Waste Origin Surface-Modified with Fe3O4 and Thiolated-Chitosan for Efficacious Immobilization of Laccase

“…The term "circular economy" was predominantly developed by the Ellen MacArthur Foundation [20]. This can be archived by two major routes: Those from where biodegradable waste having nutrients are suitable to return to nature or reuse [21][22][23] and non-degradable waste needs cycling for biopolymers to reduce pollution, for the paper sector as well [24]. However, cellulose fiber processing from paper pulp involves different chemical-physical processes and specific operating conditions to facilitate the dissolution and regeneration of cellulose materials [25][26][27][28][29].…”