title: Production of alpha-amylase from Aspergillus oryzae for several industrial applications in a single step.
abstract: A one-step method as a strategy of alpha-amylase concentration and purification was developed in this work. This methodology requires the use of a very low concentration of biodegradable polyelectrolyte (Eudragit(®) E-PO) and represents a low cost, fast, easy to scale up and non-polluting technology. Besides, this methodology allows recycling the polymer after precipitation. The formation of reversible soluble/insoluble complexes between alpha-amylase and the polymer Eudragit(®) E-PO was studied, and their precipitation in selected conditions was applied with bioseparation purposes. Turbidimetric assays allowed to determine the pH range where the complexes are insoluble (4.50-7.00); pH 5.50 yielded the highest turbidity of the system. The presence of NaCl (0.05M) in the medium totally dissociates the protein-polymer complexes. When the adequate concentration of polymer was added under these conditions to a liquid culture of Aspergillus oryzae, purification factors of alpha-amylase up to 7.43 and recoveries of 88% were obtained in a simple step without previous clarification. These results demonstrate that this methodology is suitable for the concentration and production of alpha-amylase from this source and could be applied at the beginning of downstream processing.
authors.affiliation: Departamento de Tecnología, Facultad de Ciencias Bioquímicas y Farmacéuticas. Universidad Nacional de Rosario, IPROBYQ-CONICET, Suipacha 531 (S2002RLK), Rosario, Argentina.
authors.forename: María C
authors.initials: MC
authors.lastname: Porfirif
authors.affiliation: Departamento de Tecnología, Facultad de Ciencias Bioquímicas y Farmacéuticas. Universidad Nacional de Rosario, IPROBYQ-CONICET, Suipacha 531 (S2002RLK), Rosario, Argentina.
authors.forename: Esteban J
authors.initials: EJ
authors.lastname: Milatich
authors.affiliation: Departamento de Tecnología, Facultad de Ciencias Bioquímicas y Farmacéuticas. Universidad Nacional de Rosario, IPROBYQ-CONICET, Suipacha 531 (S2002RLK), Rosario, Argentina.
authors.forename: Beatriz M
authors.initials: BM
authors.lastname: Farruggia
authors.affiliation: Departamento de Tecnología, Facultad de Ciencias Bioquímicas y Farmacéuticas. Universidad Nacional de Rosario, IPROBYQ-CONICET, Suipacha 531 (S2002RLK), Rosario, Argentina. Electronic address: dromanini@conicet.gov.ar.
authors.forename: Diana
authors.initials: D
authors.lastname: Romanini
mesh_terms: D001236:Aspergillus oryzae / Q000201:enzymology* / Q000378:metabolism*; D001709:Biotechnology; D005656:Fungal Proteins / Q000032:analysis / Q000302:isolation & purification* / Q000378:metabolism; D011108:Polymers; D012995:Solubility; D000516:alpha-Amylases / Q000032:analysis / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D011108:Polymers; D000516:alpha-Amylases
keywords: Alpha-amylase; Aspergillus oryzae; Bioseparation; Enzymes; Intelligent polymer