title: Partition in aqueous two-phase system: its application in downstream processing of tannase from Aspergillus niger.
abstract: Tannase from Aspergillus niger was partitioned in aqueous two-phase systems composed by polyethyleneglycol of molar mass 400, 600 and 1000 and potassium phosphate. Tannase was found to be partitioned toward the salt-rich phase in all systems, with partition coefficients lower than 0.5. Partition coefficients values and low entropic and enthalpic changes associated with tannase partition suggest that the entropic effect may be the driving force of the concentration of the enzyme in the bottom phase due to the high molar mass of the enzyme. The process was significantly influenced by the top phase/bottom phase volume ratio. When the fungal culture broth was partitioned in these systems, a good performance was found, since the enzyme recovery in the bottom phase of the system composed by polyethyleneglycol 1000 was around 96% with a 7.0-fold increase in purity.
authors.affiliation: Food Research Department, School of Chemistry, Universidad Autónoma de Coahuila, Saltillo, Coahuila, Mexico.
authors.forename: Luis V
authors.initials: LV
authors.lastname: Rodríguez-Durán
authors.forename: Darío
authors.initials: D
authors.lastname: Spelzini
authors.forename: Valeria
authors.initials: V
authors.lastname: Boeris
authors.forename: Cristóbal N
authors.initials: CN
authors.lastname: Aguilar
authors.forename: Guillermo A
authors.initials: GA
authors.lastname: Picó
mesh_terms: D000178:Acrylamides / Q000737:chemistry; D001234:Aspergillus niger / Q000201:enzymology*; D002265:Carboxylic Ester Hydrolases / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D002942:Circular Dichroism; D003470:Culture Media; D005285:Fermentation; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000737:chemistry; D011506:Proteins / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013696:Temperature
chemical_list: D000178:Acrylamides; D003470:Culture Media; D011506:Proteins; D011092:Polyethylene Glycols; D002265:Carboxylic Ester Hydrolases; C022711:tannase