| 摘要 |
PURPOSE:To readily obtain a galactooligosaccharide in good yield and high purity by treating lactose with a prescribed beta-galactosidase, adding a beta- galactosidase different from that described above the the resultant treated solution and carrying out the second enzyme treatment. CONSTITUTION:A lactose-containing substance, such as lactose or whey, is dissolved in hot water so as to provide 10-90wt./vol.% lactose to afford a substrate solution. A beta-galactosidase derived from Bullera.singularis or Bacillus.circulans in an amount of 1-100 units/ml is added to the obtained substrate solution to carry out the first enzymic treatment at a desired pH an temperature. A beta-galactosidase derived from Streptococcus.thermophilus or Lactobacillus.bulgaricus is then added thereto to carry out the second enzymic treatment under the same conditions as those described above to produce a galactooligosaccharide expressed by the formula (Gal is galactose residue; Glc is glucose residue; n is 1-4). |
