Authors: YJ Lee C S Kim DK Oh
Publish Date: 2003/12/13
Volume: 64, Issue: 6, Pages: 787-793
Abstract
Lactulose production from lactose and fructose was investigated with several commercial βgalactosidases The enzyme from Kluyveromyces lactis exhibited the highest lactulose productivity among the βgalactosidases tested The reaction conditions for lactulose production were optimized using cells that had been permeabilized by treatment with 50 v/v ethanol cell concentration 104 g l−1 concentration of substrates 40 w/v lactose and 20 w/v fructose temperature 60°C pH 70 Under these conditions the permeabilized cells produced approximately 20 g l−1 lactulose in 3 h with a lactulose productivity of 68 g l−1 h−1 These results represent 13 and 21fold increases in lactulose concentration and productivity compared with untreated washed cells This is the first reported trial of enzymatic synthesis of lactulose using permeabilized yeast cells
Keywords: