title: Liquid-liquid extraction of commercial glucose oxidase by reversed micelles.
abstract: Aim of this work was to establish the optimum operating conditions for the extraction and recovery by cationic reversed micelles of commercial glucose oxidase (GOX) from Aspergillus niger, in view of possible application to raw cell homogenates. The influence of pH, temperature, electric conductivity and solvent/co-solvents ratio on the extraction was investigated by a fractional factorial design of 2(3-1) type, conjugated with a mixture experimental design, using the residual enzyme activity to evaluate the results. The best conditions for GOX extraction were ensured using isooctane as solvent and hexanol and butanol as co-solvents at 76/6/18 volume ratio, pH 6.0, 0.2 M cetyl trimethylammonium bromide (CTAB) as cationic surfactant, and electrical conductivity (kappa) of 4.8 mS cm-1. The highest yield of GOX activity recovery (about 90%) was in fair accordance with the value predicted by the model.
authors.affiliation: Biotechnology Interunit Post-graduation Program IPT/Butantã/USP, P.O. Box 66083, São Paulo, SP, Brazil.
authors.forename: Luis Fernando Peffi
authors.initials: LF
authors.lastname: Ferreira
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Taqueda
authors.forename: Michele
authors.initials: M
authors.lastname: Vitolo
authors.forename: Attilio
authors.initials: A
authors.lastname: Converti
authors.forename: Adalberto
authors.initials: A
authors.lastname: Pessoa
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D002498:Centrifugation / Q000379:methods*; D005591:Chemical Fractionation / Q000379:methods*; D003102:Colloids / Q000737:chemistry* / Q000302:isolation & purification*; D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D003198:Computer Simulation; D005949:Glucose Oxidase / Q000302:isolation & purification*; D008823:Micelles; D008956:Models, Chemical; D012996:Solutions
chemical_list: D003102:Colloids; D008823:Micelles; D012996:Solutions; D005949:Glucose Oxidase