Galacto Oligosaccharide comprises galactose residues that make up an oligosaccharide and the end contains glucose as a component.
What is Galacto Oligosaccharide?
Galacto Oligosaccharide is an organic oligosaccharide i.e., carbohydrate consisting of 3-8 saccharide units. Oligosaccharides differ from polysaccharides another complex carbohydrate, based on the saccharide units that make them as oligosaccharides comprise fewer saccharides about 3-10. Simple sugars are easily digested unlike polysaccharides and are formed of 1 or 2 saccharide units and they provide energy rapidly as they are digested readily. While polysaccharides are complex and take more time to be metabolized and digested. They don’t cause an incline in blood sugar levels as simple sugars.
Galacto Oligosaccharide Properties
Galacto Oligosaccharide comprises residues of galactose that are dietary monosaccharides. Their chain length can differ according to units of galactose residue present. These complex polysaccharides contain C-C and C-H covalent bonds and are hence organic. It has a greater sweetness than sucrose by 0.3-0.6 times so it has industrial applications as an alternative sweetener. It can be semi-synthetically produced.
It can also be employed to reduce the freezing point of foods and as a humectant, as it can retain moisture well. It can be produced synthetically by bovine milk by converting lactose present in it and can be catalyzed by β-galactosidases.
Galacto Oligosaccharide is biosynthesized for utilizing as an energy reserve in certain organisms and is similar to fructooligosaccharide. Particular root vegetables and beans in the process of storing their energy reserves produce Galacto Oligosaccharide.It is produced by the process of dehydration synthesis. Glycosidic bonds link galactose residues together.
As they are complex, in case of humans they are non-digestible as it is readily absorbed in the intestines. Enzymes like salivary amylase cannot break complex Galacto Oligosaccharide. Most of the Galacto Oligosaccharide if ingested will be fermented by microbes in the large intestine. They together with fructooligosaccharide constitute dietary fiber and they also are grouped under prebiotics as they support the growth of beneficial gut bacteria. These microbes ferment and cleave them into SCFAs that act as fuel and short-chain fatty acids.
Biological Importance of Galacto Oligosaccharide
Galacto Oligosaccharide is an important reserve of oligosaccharides in organisms. But other organisms like humans lack the enzymes required to metabolize them as those genes are lacking in them. It is a common soluble dietary fiber and oligosaccharide that aids in healthy bowel movements and promotes better gut health functioning as a prebiotic. It is metabolized by fermentation by gut bacteria like lactobacilli and bifidobacterial.
These bacteria produce isoprenoid precursors, conjugated linoleic acid isomers, bioactive peptides, and vital vitamins. Their growth also inhibits the growth of other detrimental gut bacteria like Clostridia, Salmonella typhimurium, etc. Based on the SCFAs, the caloric value of Galacto Oligosaccharide of 1-2 kcal/g.
Galacto Oligosaccharide Health Risk
While Galacto Oligosaccharide is good for gut health, too much consumption can cause abdominal bloating, intestinal upset, flatulence, and cramps. Their recommended ingestion is 20 g per day.
Sensitivity to Galacto Oligosaccharide reported in some people and can activate the immune system, so people having autoimmune diseases are asked to reduce Galacto Oligosaccharide consumption.
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