Continuous counter-current purification of glucose-6-phosphate dehydrogenase using liquid–liquid extraction by reverse micelles

This work details the continuous counter-current purification of glucose-6-phosphate dehydrogenase from Saccharomyces cerevisiae cells by liquid–liquid extraction using reverse micelles. A biocompatible reverse micellar system consisting of 0.05 M soybean lecithin (zwiterionic surfactants) in isooctane with hexanol was employed to study the influence of different flow-rates on G6PD purification. The results showed that the reverse micellar system was able to remove proteins (impurities) from the cell-free. The enzyme recovery yield varied from 32% to 115% and G6PD purification factor from 1.0 to 2.2, under flow-rates ranging from 1.6:1.6 mL min−1 to 6.0:6.0 mL min−1 for both phases (micellar and aqueous phases). The steady hold-up values demonstrated that the mass transfer capability of this extraction apparatus was practically constant. The continuous counter-current purification system employed proved to be useful not only for purifying G6PD, but also for maintaining the enzyme activity.