Galactose from lactose

Millon s reagent Dissolve one part of mercury in two parts of nitric acid (d. 142) first in the cold and then by warming. Dilute the solution with two volumes of water. 

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In another case, Thiem et al. used a fS-galactosidase from bovine testes in the transfer of a galactose from lactose to glucose or galactose-containing structures with yields ranging from 7% to 44% (16). The enzyme showed a preference for the formation of fSl,3-linkage. 

Disaccharides — monosaccharides (glucose and galactose from lactose fructose from other sources) Polysaccharides — glucose... 

The two major monosaccharides, other than glucose, that enter the bloodstream from the diet are fructose from sucrose and galactose from lactose. In both cases these hexoses are metabolically transformed and enter the early stages of the glycolytic pathway. 

J. S. Butts, The Comparative Ketolytic Action of Glucose, Galactose and Lactose When Administered to Rats Suffering from an Artificial Ketosis, Dissertation, University of Southern California (1933). 

This enzyme [EC 2.4.1.22] is a protein complex of two proteins (designated A and B) and catalyzes the reaction of UDP-galactose with D-glucose to generate UDP and lactose. In the absence of the ce-lactalbumin (protein B), the enzyme catalyzes the transfer of galactose from UDP-galactose to A-acetylglucosamine (Le., the activity of A-acetyllactosamine synthase, EC 2.4.1.90). 

Figure 10.12 Metabolism of lactose by lactic acid bacteria many Lactobacillus species/strains can not metabolize galactose (from Cogan and Hill, 1993).

Therapy Rapid diagnosis and removal of galactose (therefore, lactose) from the diet. 

Dulcitol occurs in plants (manna from Madagascar). It can also be obtained by reduction of D-galactose or lactose. 

In the initial studies, as briefly described earlier, the methyl a-2-thioglycoside of Neu5Ac 5 [22,24], or the -1 1 anomeric mixture 11 [26,27], which can be almost quantitatively prepared from 9 in one step, was coupled with lightly protected sugar acceptors such as 14,16, and 18 in the presence of DMTST in acetonitrile to give exclusively the sialyl a(2—>3)- or sialyl ot(2—>6)-D-galactose or lactose derivatives (20, 22, and 24) in 50-70% yields even in large-scale reactions [26],... 

Isolactose is a disaccharide arising when a mixture of glucose and galactose is treated with Kefir extract (1902). It is different from lactose and melibiose, and forms a crystalline phenylosazone. 

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