title: Transgalactosylation and hydrolytic activities of commercial preparations of β-galactosidase for the synthesis of prebiotic carbohydrates.
abstract: β-Galactosidases exhibit both hydrolytic and transgalactosylation activities; the former has been used traditionally for the production of delactosed milk and dairies, while the latter is being increasingly used for the synthesis of lactose-derived oligosaccharides: balance between both activities was highly dependent on the enzyme origin: β-galactosidases from Aspegillus oryzae and Bacillus circulans exhibited high transgalactosylation activity, while those from one from Kluyveromyces exhibited high hydrolytic activity but quite low transgalactosylation activity. Also the affinity for the donors (lactose or lactulose) and the acceptors (lactose, lactulose or fructose) of transgalactosylated galactose was dependent on the enzyme origin, as reflected by the Michaelis constants obtained in the synthesis of galacto-oligosaccharides, fructosyl-galacto-oligosaccharides and lactulose. Finally, the balance between transgalactosylation and hydrolytic activities of β-galactosidases could be tuned by changing the concentration of galactose donor.
authors: School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2147, Valparaíso, Chile. Electronic address: c.siancas@gmail.com.
authors: Cecilia
authors: C
authors: Guerrero
authors: School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2147, Valparaíso, Chile.
authors: Carlos
authors: C
authors: Vera
authors: School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2147, Valparaíso, Chile.
authors: Raúl
authors: R
authors: Conejeros
authors: School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2147, Valparaíso, Chile.
authors: Andrés
authors: A
authors: Illanes
mesh_terms: D001236:Aspergillus oryzae / Q000201:enzymology; D001407:Bacillus / Q000201:enzymology; D001709:Biotechnology; D002241:Carbohydrates / Q000096:biosynthesis*; D005632:Fructose / Q000378:metabolism; D005690:Galactose / Q000378:metabolism; D006031:Glycosylation; D006868:Hydrolysis; D007700:Kinetics; D007716:Kluyveromyces / Q000201:enzymology; D007785:Lactose / Q000378:metabolism; D007792:Lactulose / Q000378:metabolism; D009844:Oligosaccharides / Q000096:biosynthesis; D056692:Prebiotics / Q000032:analysis; D013045:Species Specificity; D001616:beta-Galactosidase / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D002241:Carbohydrates; D009844:Oligosaccharides; D056692:Prebiotics; D005632:Fructose; D007792:Lactulose; D001616:beta-Galactosidase; D007785:Lactose; D005690:Galactose
keywords: Fructosyl-galacto-oligosaccharides; Galacto-oligosaccharides; Lactulose; Prebiotic carbohydrates; β-Galactosidase