Galactose (galacto- + -ose, “milk sugar”), sometimes abbreviated Gal, is a monosaccharide sugar that is less sweet than glucose and fructose. It is a C-4 epimer of glucose.
Galactose is found in dairy products, sugar beets, other gums and mucilages. It is also synthesized by the body, where it forms part of glycolipids and glycoproteins in several tissues; and is a by-product from the third-generation ethanol production process (from macroalgae).
When combined with glucose (monosaccharide), through a condensation reaction, the result is the disaccharide lactose. The hydrolysis of lactose to glucose and galactose is catalyzed by the enzymes lactase and β-galactosidase. The latter is produced by the lac operon in Escherichia coli. In nature, lactose is found primarily in milk and milk products. Consequently, various food products made with dairy-derived ingredients, e.g. breads and cereals, can contain lactose. Galactose metabolism, which converts galactose into glucose, is carried out by the three principal enzymes in a mechanism known as the Leloir pathway. The enzymes are listed in the order of the metabolic pathway: galactokinase (GALK), galactose-1-phosphate uridyltransferase (GALT), and UDP-galactose-4’-epimerase (GALE).
In the human body, glucose is changed into galactose via hexoneogenesis to enable the mammary glands to secrete lactose. However, most lactose in breast milk is synthesized from galactose taken up from the blood, and only 35±6% is made from galactose from de novo synthesis. Glycerol also contributes some to the mammary galactose production.
Source: Wikipedia
Galactose
Chromatogram(s) using Benson Polymeric Columns
Part No.:
Eluent:
Flow Rate:
Detection:
Temperature:
Sample Size:
Column Size:
Resin Type:
DI H2O
0.5 ml/min
RI
80 C
20 ul, 30 mg/ml
300 x 7.8 mm
6% Ca
2 – DP4
3 – DP3
4 – Maltose
5 – Glucose
6 – Galactose
7 – Fructose
8 – Mannitol
9 – Sorbitol
Part No.:
Eluent:
Flow Rate:
Detection:
Temperature:
Sample Size:
Column Size:
Resin Type:
DI H2O
0.4 ml/min
RI
90 C
20 ul, 30 mg/ml
300 x 7.8 mm
6% Pb
2 – Maltose
3 – Xylose
4 – Galactose
5 – Mannose
6 – Glycerol
Part No.:
Eluent:
Flow Rate:
Detection:
Temperature:
Sample Size:
Column Size:
Resin Type:
DI H2O
0.8 ml/min
RI
80 C
20 ul, 30 mg/ml
300 x 7.8 mm
8% Pb
2 – Glucose
3 – Xylose
4 – Galactose
5 – Arabinose
6 – Xylitol
7 – Sorbitol
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