Production of lactosucrose from sucrose and lactose by a levansucrase from Zymomonas mobilis.
Lactosucrose (4(G)-beta-D-galactosylsucrose) is an oligosaccharide consisting of galactose, glucose, and fructose. In this study, we prepared lactosucrose from lactose and sucrose using a levansucrase derived from Zymomonas mobilis. Optimum conditions for lactosucrose formation were 23 degrees C, pH 7.0, 18.0% (w/v) lactose monohydrate, and 18% (w/v) sucrose as substrates, and 1 unit of enzyme/ml of reaction mixture. Under these conditions, the lactosucrose conversion efficiency was 28.5%. The product was purified and confirmed to be O-beta-D-galactopyranosyl-(1-->4)-O-beta-D-glucopyranosyl- (1-->2)-beta-D-fructofuranoside, or lactosucrose. A mixed-enzyme system containing a levansucrase and a glucose oxidase was applied in order to increase the efficiency of lactose and sucrose conversion to lactosucrose, which rose to 43.2% as s result.
Han
Woo-Cheul
WC
Department of Food and Nutrition, Kangwon National University, Gangwon 245-711, Korea.
Byun
Sun-Ho
SH
Kim
Mi-Hyun
MH
Sohn
Eun Hwa
EH
Lim
Jung Dae
JD
Um
Byung Hun
BH
Kim
Chul Ho
CH
Kang
Soon Ah
SA
Jang
Ki-Hyo
KH
D001426:Bacterial Proteins / Q000378:metabolism*; D006602:Hexosyltransferases / Q000378:metabolism*; D007785:Lactose / Q000235:genetics*; D013395:Sucrose / Q000378:metabolism*; D014312:Trisaccharides / Q000378:metabolism*; D017355:Zymomonas / Q000201:enzymology / Q000378:metabolism*
D001426:Bacterial Proteins; D014312:Trisaccharides; D013395:Sucrose; C081752:galactosucrose; D006602:Hexosyltransferases; C021513:levansucrase; D007785:Lactose