Lactose maximum product synthesis

The transfer galactosylation with /3-galactosidase from Bacillus circulans for the synthesis of N-acetyllactosamine starting from lactose and N-acetylglucosamine [44] has been studied. When performing the reaction in an aqueous system the problem of this approach lies in the secondary hydrolysis of the product by the same enzyme. As a consequence, yields are less than 30%, and it is important to separate enzyme and product when the maximum yield is obtained. By addition of 25% v/v of [MMIM][MeS04] as a water-miscible co-solvent the water activity of the medium is decreased and, consequently, the secondary hydrolysis of the... 

The j8-galactosidase from the Pencillium simplicissimum isolated from soil has high galactosyltransferase activity Synthesis of galactoohgosaccharides from 3 to 4 units of monosaccharide. When monosaccharides are present in the reaction system, the transfer activity of the enzyme will be inhibited, so only by the enzyme from P. simplicissimum cultured under the non-optimum hydrolysis conditions, galactooligosaccharide production can reach the maximum. For example, the lactose solution (concentration of 60%) incubated at pH 6.5 and 50 C obtained the maximum conversion rate. The product composition was 30.5% galacto-ohgosaccharide, 27.5% residual lactose and 42% free monosaccharides. 

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