title: Recovery and purification of a Kluyvermyces lactis β-galactosidase by Mixed Mode Chromatography.
abstract: Mixed Mode Chromatography (MMC) is a potential separation technique that allows simultaneous ionic and hydrophobic interactions between the adsorbent and the adsorbate. The aim of this work was to assess the recovery and purification of a Kluyveromyces lactis β-galactosidase employing MMC. Protein precipitation and dialysis were performed in order to concentrate the enzyme of interest and eliminate cell debris and other interferences inherent in the fermentation medium. The best conditions for both adsorption and desorption were attained by a non-factorial Central Composite Experimental Design and employed in the chromatographic runs with resin CAPTO MMC. Fermentation yielded mean values of total enzyme concentration of 0.44 mg/mL, enzymatic activity (employing lactose as a substrate) of 74 U/mL and specific activity of 168 U/mg. The Purification Factor (PF) obtained was of 1.17. After precipitation and dialysis, the subsequent chromatographic run resulted in recovery values ​​of 41.0 and 48.2% of total protein concentration and enzymatic activity, respectively. SDS-PAGE electrophoresis confirmed the purification evolution throughout the unit operations employed, attesting the feasibility of the technique to obtain enzymes with not only considerable degree of purity but also possessing high-added value.
authors.affiliation: Universidade Federal do Ceará, Departamento de Engenharia Química, Campus do Pici, S/N-Bloco 709-CEP, Ramal 206, 60455-760 Fortaleza, CE, Brazil.
authors.forename: Micael de Andrade
authors.initials: MA
authors.lastname: Lima
authors.affiliation: Universidade Federal do Ceará, Departamento de Engenharia Química, Campus do Pici, S/N-Bloco 709-CEP, Ramal 206, 60455-760 Fortaleza, CE, Brazil.
authors.forename: Maria de Fátima Matos de
authors.initials: MFM
authors.lastname: Freitas
authors.affiliation: Universidade Federal do Ceará, Departamento de Engenharia Química, Campus do Pici, S/N-Bloco 709-CEP, Ramal 206, 60455-760 Fortaleza, CE, Brazil.
authors.forename: Luciana Rocha Barros
authors.initials: LRB
authors.lastname: Gonçalves
authors.affiliation: Universidade Federal do Ceará, Departamento de Engenharia Química, Campus do Pici, S/N-Bloco 709-CEP, Ramal 206, 60455-760 Fortaleza, CE, Brazil. Electronic address: ivanildo@gpsa.ufc.br.
authors.forename: Ivanildo José da
authors.initials: IJD
authors.lastname: Silva Junior
mesh_terms: D000327:Adsorption; D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D002853:Chromatography, Liquid / Q000379:methods*; D007716:Kluyveromyces / Q000737:chemistry / Q000201:enzymology*; D017711:Nonlinear Dynamics; D001616:beta-Galactosidase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D001616:beta-Galactosidase
keywords: Adsorption; Biomolecule recovery and purification; Mixed Mode Chromatography