Enzymatic production of lactulose by fed-batch and repeated fed-batch reactor.

The effects of the most significant operational variables on reactor performance of fed-batch and repeated fed-batch were evaluated in the lactulose production by enzymatic transgalactosylation. Feed flowrate in the fed stage (F) and fructose to lactose molar ratio (Fr/L) were the variables that mostly affected the values ​​of lactulose yield (Y), lactulose productivity (π) and selectivity of transgalactosylation (S/). Maximum Y of 0.

Synthesis of Lactulose in Continuous Stirred Tank Reactor With β-Galactosidase of Immobilized in Monofunctional Glyoxyl Agarose Support.

Lactulose synthesis from fructose and lactose in continuous stirred tank (CSTR) reactor operation with glyoxyl-agarose immobilized β-galactosidase is reported for the first time. The effect of operational variables: inlet concentrations of sugar substrates, temperature, feed substrate molar ratio, enzyme loading and feed flow rate was studied on reactor performance. Even though the variation of each one affected to a certain extent lactulose yield (Y ), specific productivity (π ) and selectivity of the reaction (lactulose/transgalactosylated oligosaccharides molar ratio) (S ), the most significant effects were obtained by varying the inlet concentrations of sugar substrates and the feed substrate molar ratio.

Continuous enzymatic synthesis of lactulose in packed-bed reactor with immobilized Aspergillus oryzae β-galactosidase.

Lactulose synthesis from fructose and lactose in continuous packed-bed reactor operation with glyoxyl-agarose immobilized Aspergillus oryzae β-galactosidase is reported for the first time. Alternative strategies to conventional batch synthesis have been scarcely explored for lactulose synthesis. The effect of flow rate, substrates ratio and biocatalyst-inert packing material mass ratio (M/M) were studied on reactor performance.