Galactose and lactose

The major source of absorbable D-galactose in the diet of man and many of the higher animals is lactose. The latter occurs only in milk as a product of the mammary gland hence, these sugars are of special importance in the nutrition of all young mammals and older persons and animals that ingest appreciable amounts of milk. 

The rate of absorption of galactose from the alimentary tract exceeds that of D-glucose, D-fructose, and D-mannose. In the rat, glycogen is formed more slowly from galactose than from glucose (27), and galactose differs from glucose in many respects. 

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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). 

A. Hasegawa, T. Nagahama, H. Ohki, K. Hotta, H. Ishida, and M. Kiso, Reactivity of glycosyl promoters in a-glycosylation of W-acetylneuraminic acid with the primary and secondary hydroxyl groups in the suitably protected galactose and lactose derivatives, J. Carbohydr. Chem. 70 493 (1991). 

The most common treatment is to remove galactose (and lactose) from the diet. The enigma of galactosemia is that, although elimination of galactose from the diet prevents liver disease and cataract development, the majority of patients still suffer from central nervous system malfunction, most commonly a delayed acquisition of language skills. Females will also display ovarian failure. 

Storage diseases Some of the genetic metabolic diseases require special dietary measures, e.g. (1.) disorders of the urea cycle are treated by means of a diet similar to that applied in encephalopathy (s. p. 594), (2.) Gierke s disease necessitates a high-carbohydrate diet (s. p. 595), (i.) Cori s disease is treated with formula diets and a starch diet (s. p. 596), (4.) galactosaemia requires a galactose-and lactose-free diet (s. p. 597), and (5.) in fructose intolerance, a fructose- and saccharose-free diet must be given, (s. p. 597)... 

H.-K. Ishida, H. Ishida, M. Kiso, and A. Hasegawa, a-Stereocontrolled, glycoside synthesis of trimeric sialic acid with galactose and lactose derivatives, 3. Carbohydr. Chem. 73 655 (1994). 

Further inferences may be made from the associations between other pairs of substrates Krzanowski and Barnett667 discussed the interpretation and handling of the numbers in these tables of association. It should be borne in mind that interpretation of some associations in terms of catabolic routes may prove quite incorrect. Rather, the associations might result from close genetic linkage this is likely to apply to the associations between D-galactose and lactose or meli-biose (see Table XVI, squares K1 and Jl). 

This is a nonspecific reaction for reducing substances. If the test is carefully performed under controlled conditions, it can detect as little as 30 mg/100 ml of glucose. Fructose and ketopentoses will effect reduction when the reaction mixture is heated to 55°C for 10 minutes, whereas glucose, galactose, and lactose will not (L3). 

The facile dehydrogenation of o-glucose and related mono- and disaccharides such as D-galactose and lactose on platinum or rhodium catalysts under alkaline conditions (pH 13.5) has been reported [49]. During this reaction, hydrogen was evolved whereas o-glucose was transformed into o-gluconic acid. Other metals, e. g. nickel, palladium, and ruthenium, were less active and much less selective (Scheme 4). 

Strain Pseudomonas cepacia ATCC 17749 was stored under liquid nitrogen for longer storing periods at the institutes strain collection. For culture maintenance the strain was grown on solid media for two to three days at 30 °C on LB medium and on mineral medium with various carbon sources (glucose, galactose and lactose) respectively. Then the plates were kept at 4 °C. Fresh plates were inoculated every two to three weeks. 

The basic synthetic mineral medium for the fermentations and plates was described earlier. Ammonium sulfate was the sole nitrogen source. Maximum concentrations of ammonium sulfate were 2,4 g/L. Carbon sources for the plates and fomentations were glucose, galactose and lactose. The initial concentration of carbon sources was about 10 g/L. Sodium valerate was added in concentrations not exceeding 2 g/L during polymer accumulati[Pg.140]

Restrict Galactose (and lactose), fructose (and sucrose), excessive fat Supplement Carbohydrate (uncooked cornstarch)... 

Icosapentaenoic acid undergoes transformation in human platelets to give 12-hydroxy-20 5(5,8,10,14,17) as major product and 12-hydroxy-17 4(5,8,10,14) and a thromboxane as minor products. Among the many products produced from arachidonic acid by platelet lipoxygenase,8,9,12- and 8,11,l2-trihydroxy-20 3 and 10-hydroxy--11,12-epoxy-20 3 (structure uncertain) are not formed in the presence of glucose,though galactose and lactose have little effect... 

Rajendran, V. and Irudayaraj, J. 2002. Detection of glucose galactose and lactose in milk with a microdialysis-coupled flow injection amperometric sensor. J. Dairy Sci. 85 1357-1361. 

Treatment is achieved by avoiding galactose and lactose in the diet. (NB Do not confuse these conditions with lactose intolerance associated with lactase deficiency Fig. 20.1.)... 

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