The galactooligosaccharides (GOS), a group of oligosaccharides, are not digerible carbohydrates (NDOs) and are resistant to hydrolysis by intestine digestive enzymes with similar dietary fiber physiological effect. The benefits of galactooligosaccharides ingestion arise from a population of bifidobacteria in the colon that suppress the activity of putrefactive bacteria and reduce the formation of toxic fermentation products. Scopulariopsis strains showed good productivity of β-galactosidase when grown in a semi-solid fermentation medium. The aim of this work was to extract the β-galactosidase from Scopulariopsis sp. and to evaluate the temperature conditions, reaction time, lactose, and enzyme concentration to improve the GOS production. Temperatures of 35, 45, and 60 °C, reaction time at 12, 24 and 48 hours, enzyme concentrations from 0.5 to 10 U.mL-1, and 10, 25, and 40%(w/v) of lactose solution (0,1 M of acetate buffer, pH 5.0) were analyzed. The optimum conditions were 40% (w/v), at 45 °C, 10 U.mL-1 of enzyme and the optimum time was 12 hours of reaction. Under these conditions, the enzyme converted 20% of lactose into oligosaccharide (80.8 mg.mL-1 de 4'galactosyl-lactose).
functional foods; prebiotic; β-galactosidase; Scopulariopis sp.; galactooligosaccharide
