title: Liquid-liquid extraction of antimicrobial peptide P34 by aqueous two-phase and micellar systems.
abstract: Antimicrobial peptide P34 is a promising biopreservative for utilization in the food industry. In this work, aqueous biphasic systems (ABS) and aqueous biphasic micellar systems (ABMS) were studied as prestep for purification of peptide P34. The ABS was prepared with polyethylene glycol (PEG) and inorganic salts and the ABMS with Triton X-114 was chosen as the phase-forming surfactant. Results indicate that peptide P34 partitions preferentially to PEG-rich phase and extraction with ammonium sulfate [(NH4)2SO4], yielding a 75% recovery of the antimicrobial activity, specific activity of 1,530 antimicrobial units per mg of protein, and purification fold of 2.48. Protein partition coefficient and partition coefficient for the biological activity with (NH4)2SO4system were 0.48 and 64, respectively. Addition of sodium chloride did not affect recovery, but decreased protein amount in the PEG-rich phase, indicating a higher partition of biomolecules. ABMS did not yield good recovery of antimicrobial activity. Purification fold using PEG-(NH4)2SO4and 1.0 mol l-1sodium chloride was twice higher than that obtained by conventional protocol, indicating a successful utilization of ABS as a step for purification of peptide P34.
authors: a Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.|b Universidade Estadual do Rio Grande do Sul, Unidade de Encantado , Encantado , Brazil.
authors: Voltaire
authors: V
authors: Sant'Anna
authors: a Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.
authors: Ana Paula
authors: AP
authors: Folmer Correa
authors: c Departamento de Microbiologia, Instituto de Ciências Básicas da Saúde , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.
authors: Amanda
authors: A
authors: de Souza da Motta
authors: a Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.
authors: Adriano
authors: A
authors: Brandelli
mesh_terms: D000645:Ammonium Sulfate / Q000737:chemistry*; D023181:Antimicrobial Cationic Peptides / Q000302:isolation & purification*; D059625:Liquid-Liquid Extraction / Q000379:methods*; D008823:Micelles; D017830:Octoxynol; D011092:Polyethylene Glycols / Q000737:chemistry*; D012492:Salts / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D023181:Antimicrobial Cationic Peptides; D008823:Micelles; D012492:Salts; D013501:Surface-Active Agents; D011092:Polyethylene Glycols; D017830:Octoxynol; C010615:Nonidet P-40; D000645:Ammonium Sulfate
keywords: Antimicrobial; aqueous biphasic micellar system; aqueous biphasic system; peptide purification