Efficient Alkaline Isomerization of Lactose to Lactulose in the Presence of an Organogermanium Compound.
Efficient Alkaline Isomerization of Lactose to Lactulose in the Presence of an Organogermanium Compound.
复制标题
DOI：
10.5458/jag.jag.jag-2016_018
复制
发表时间：
2017
影响因子：
1.1
通讯作者：
Kasumi T
中科院分区：
文献类型：
--
作者：
Nagasawa T;Sato K;Kasumi T
乳果糖是一种广泛应用于医药和功能性食品中的双糖，它是通过乳糖异构化而产生的。乳糖和乳果糖具有醛糖-酮糖关系。使用加热下的Lobry de Bruyn-Alberda货车Ekenstein转化实现了小于25%的乳糖转化为乳果糖，而通过向反应混合物中加入约等摩尔浓度的有机锗化合物3-（三羟基锗基）丙酸（THGP）将转化率提高至80%。为了进一步理解这一现象，在这项研究中，我们分析了THGP和糖异构体之间的亲和力使用1H核磁共振光谱。对于THGP与乳糖和乳果糖的二甲基衍生物，在0.1 M（1：1混合比）下的复合物形成率分别为14和59%，复合物形成常数分别为1.8和43 M-1。乳果糖的复合物形成能力比乳糖高约24倍。此外，THGP被认为保护乳果糖免受碱降解，导致乳果糖的高产率。因此，我们得出结论，对异构化产物的高亲和力可以促进异构化，并且使用有机锗化合物促进糖异构化是将乳糖转化为乳果糖的有效方法。
Lactulose, a disaccharide widely used in pharmaceuticals and functional foods, is produced by lactose isomerization. Lactose and lactulose have an aldose–ketose relationship. Less than 25 % conversion of lactose into lactulose is achieved using the Lobry de Bruyn–Alberda van Ekenstein transformation with heating, whereas the conversion is increased to 80 % by the addition of an approximately equimolar concentration of the organogermanium compound 3-(trihydroxygermyl)propanoic acid (THGP) to the reaction mixture. To further understand this phenomenon, in this study, we analyzed the affinity between THGP and sugar isomers using 1H nuclear magnetic resonance spectroscopy. For the dimethyl derivative of THGP with lactose and lactulose, the complex formation ratios at 0.1 M (1:1 mixing ratio) were 14 and 59 %, respectively, with complex formation constants of 1.8 and 43 M–1, respectively. The complex formation capacity was approximately 24-fold higher for lactulose than for lactose. Moreover, THGP is considered to protect lactulose from alkaline degradation, resulting in high production yield of lactulose. Therefore, we concluded that high affinity for the isomerization product may promote isomerization and that promotion of sugar isomerization using an organogermanium compound is an effective method for converting lactose to lactulose.