期刊
LWT-FOOD SCIENCE AND TECHNOLOGY
卷 118, 期 -, 页码 -出版社
ELSEVIER
DOI: 10.1016/j.lwt.2019.108746
关键词
beta-galactosidase; Lactulose; Lactose; Bacillus circulans; Transgalactosylation
资金
- Chilean Fondecyt [1190104, 11180282]
- Pontificia Universidad Catolica de Valparaiso [DI 37.0/2019]
A commercial preparation of beta-galactosidase from Bacillus circulans was evaluated as catalyst in the synthesis of lactulose considering temperature, pH, initial total sugar concentration, enzyme to initial lactose mass ratio and fructose to lactose molar ratio (F/L) as variables. The results obtained in terms of selectivity (S-Lu) yield (Y-Lu) and productivity (pi(Lu)) of lactulose synthesis showed that only the initial total sugar concentration and lactose to fructose molar ratio were significant, the latter strongly affecting S-Lu. Best results were obtained at F/L of 20, being Y-Lu = 0.54, pi(LU) = 0.043 g h(-1).mg enz(-1), and S-Lu = 30.9. Under these conditions lactulose synthesis was favored over transgalactosylated oligosaccharides (TOS), due to the higher chance of transferring the galactosyl group into fructose at high B/L. Yields of lactulose and TOS depended on the enzyme origin, while their maximum concentrations were obtained at different lactose conversions (at 0.7 for lactulose and at 0.45 for TOS) and depended on the kinetics of reactions. Yields attained with Bacillus circular's beta-galactosidase are higher than obtained with enzymes from other origin at comparable conditions, so this system is a preferred option for lactulose production.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据