Galacto-oligosaccharides Production Using Permeabilized Cells of Kluyveromyces marxianus

Abstract

Galacto-oligosaccharides are non-digestible carbohydrates and are recognized as important prebiotics for than stimulation of the proliferation of lactic acid bacteria and bifidobacteria in the human intestine. GOS can be produced by a transgalactosylation reaction catalysed by ?-galactosidase enzyme, and microorganisms can be used as a source of ?-galactosidase. In this work, a process for producing GOS using permeabilized cells of Kluyveromyces marxianus CCT 7082 was proposed. The effects of the concentrations of lactose and enzyme, temperature and pH were studied using a fractional design followed by a central composite rotatable design. The optimum conditions for galacto-oligosaccharides production were found to be: lactose concentration 500 g/L, enzyme concentration 10 U/mL, 45°C and pH 7.0. Under optimized conditions, the GOS concentration, yield and productivity were 83 g/L, 16.5% and 27.6 g/L.h, respectively.