abstract
Aqueous two-phase systems (ATPS) are considered as efficient downstream processing techniques in the production and purification of enzymes, since they can be considered harmless to biomolecules due to their high water content and due to the possibility of maintaining a neutral pH value in the medium. A recent type of alternative ATPS is based on hydrophilic ionic liquids (ILs) and salting-out inducing salts. The aim of this work was to study the lipase (Candida antarctica lipase B - CaLB) partitioning in several ATPS composed of ionic liquids (ILs) and inorganic salts, and to identify the best IL for the enzyme purification. For that purpose a wide range of IL cations and anions, and some of their combinations were studied. For each system the enzyme partitioning between the two phases was measured and the purification factors and enzyme recoveries were determined. The results indicate that the lipase maximum purification and recovery were obtained for cations with a C-8 side alkyl chain, the [N(CN)(2)] anion and Its belonging to the pyridinium family. However, the highest purification parameters were observed for 1-methyl-3-octylimidazolium chloride [C(8)mim]Cl, suggesting that the IL extraction capability does not result from a cumulative character of the individual characteristics of ILs. The results indicate that the IL based ATPS have an improved performance in the lipase purification and recovery. (C) 2011 Elsevier B.V. All rights reserved.
keywords
AQUEOUS BIPHASIC SYSTEMS; 2-PHASE SYSTEMS; PARTITIONING BEHAVIOR; MUTUAL SOLUBILITIES; POLYETHYLENE-GLYCOL; SELF-AGGREGATION; PENICILLIN-G; EXTRACTION; PROTEINS; SALT
subject category
Biochemistry & Molecular Biology; Chemistry
authors
Ventura, SPM; Sousa, SG; Freire, MG; Serafim, LS; Lima, AS; Coutinho, JAP
our authors
Luísa Seuanes Serafim
Assistant Professor
Mara Guadalupe Freire Martins
Coordinating Researcher
Sónia Patrícia Marques Ventura
Assistant ProfessorGroups
G4 - Renewable Materials and Circular Economy
G5 - Biomimetic, Biological and Living Materials
acknowledgements
The authors are grateful for financial support from Fundacao para a Ciencia e a Tecnologia for the Ph.D. grant SFRH/BD/37830/2007 of S.P.M. Ventura and from CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior) for the post-doctoral scholarship of A.S. Lima (process number 2185/09-1).