Table of Contents
Carbohydrates seem to be organic compounds made up of carbon, hydrogen, and oxygen in a 1:2:1 ratio. They are one of the most important types of biomolecules. They are a vital source of energy. They also function as structural elements. They are categorized into two categories as nutrients: simple carbohydrates and complex carbohydrates. Simple carbohydrates, also known as sugar, are those that are easily digested and provide a quick source of energy. Complex carbohydrates (saccharide polymers) require more time to digest and metabolise. They are frequently high in fibre and, unlike simple carbohydrates, are less likely to cause blood sugar spikes.
Overview
Oligosaccharides can be any carbohydrate-containing three to six simple sugar units (monosaccharides). By partially breaking down more complex carbohydrates, a large number of oligosaccharides have been prepared (polysaccharides). The major part of the few naturally occurring oligosaccharides is found in plants. Raffinose is a trisaccharide found in a variety of plants that is made up of melibiose (galactose and glucose) and fructose. Gentianose is another plant trisaccharide. Maltotriose, a glucose trisaccharide, is found in some plants and in the blood of certain arthropods. Regarding the bad symptoms sometimes associated with the consumption of oligosaccharides, there is also evidence to suggest that they may be associated with some positive health outcomes similar to those thought to be linked with dietary fibre.
Oligosaccharides
An oligosaccharide is a saccharide polymer that contains a small number of monosaccharides (typically three to ten) (simple sugars). Oligosaccharides can perform a variety of functions, including cell recognition and binding. Glycolipids, for example, play an important role in the immune response.
Glycans are oligosaccharide chains that are linked to lipids or compatible amino acid side chains in proteins via N- or O-glycosidic bonds. N-linked oligosaccharides are always pentasaccharides attached to asparagine via a beta linkage to the side chain’s amine nitrogen. Alternatively, O-linked oligosaccharides are typically attached to threonine or serine on the side chain’s alcohol group. Natural oligosaccharides do not all occur as components of glycoproteins or glycolipids. Some, such as the raffinose series, are found in plants as storage or transport carbohydrates. Others, such as maltodextrins and cellodextrins, are produced by the microbial breakdown of larger polysaccharides like starch or cellulose.
Types of oligosaccharides
The number of monosaccharides in oligosaccharides can be used to classify them. A few of them are discussed further below:
Trisaccharides are oligosaccharides that are made up of three monosaccharides. Examples include nigerotriose, which consists of three glucose units joined by α(1→3) glycosidic linkage, maltotriose, which consists of three glucose units joined by (1→4) glycosidic links, melezitose (glucose-fructose-glucose), maltotriulose (glucose-glucose-fructose), raffinose (galactose-glucose-fructose (glucose-fructose-fructose).
Tetrasaccharides are four-monosaccharide oligosaccharides. Examples include nigerotetraose 4 glucose units joined by α(1→3) glycosidic linkage, maltotetraose 4 glucose units joined by (1→4) glycosidic linkage, lychnose (galactose-glucose-fructose-galactose), nystose (glucose-fructose-fructose), sesamose (galactose (galactose-galactose-glucose-fructose).
Pentasaccharides are made up of five sugar units. The majority of N-linked oligosaccharides are pentasaccharides. Hexasaccharides are oligosaccharides with six sugar units. α-Cyclodextrin is one such example. It is made up of six glucose units connected by α-1, 4 linkages. Heptasaccharides are oligosaccharides with seven sugar units, octasaccharides with eight, nonasaccharides with nine, decasaccharides with ten, and so on.
Oligosaccharides examples
Oligosaccharides are carbohydrates that contain between 3 and 10 single sugar residues and are not as common in the diet as other, more common carbohydrates such as those in the disaccharide category. Raffinose, stachyose, and verbascose are examples of common oligosaccharides.
Oligosaccharides (sucrose, lactose, maltose)
Sucrose is a sugar that is composed of one molecule of glucose and one molecule of fructose joined together. That’s a disaccharide, which means it’s made up of two monosaccharides: glucose and fructose. Sucrose is a naturally occurring sugar that is refined and crystallised from plants. It possesses the molecular formula C12H22O11.
Sucrose is derived and refined from sugarcane or sugar beets for human consumption. The sugar mills, which are usually located in tropical areas near sugarcane growing areas, crush the cane and produce raw sugar, which is then shipped to other factories for refining into pure sucrose. Sugar beet factories are located in temperate climates where the beet is grown and directly process the beets into refined sugar. The raw sugar crystals are washed before being dissolved into a sugar syrup, which is then filtered and passed over carbon to remove any residual colour. The sugar syrup is then concentrated by boiling under a vacuum and crystallised as the final purification process to produce clear, odourless, and sweet crystals of pure sucrose.
Lactose (disaccharide) is a sugar with the molecular formula C12H22O11 that is made up of galactose and glucose subunits. Lactose accounts for approximately 2–8% of milk (by weight). The name is derived from lac (gen. lactis), the Latin word for milk, and the sugar suffix -ose. The compound is a white, non-hygroscopic, water-soluble solid with a mildly sweet taste. It’s common in the food industry.
Lactose has been hydrolyzed to glucose and galactose, isomerized to lactulose in alkaline solution, and catalytically hydrogenated to the corresponding polyhydric alcohol, lactitol. Lactulose is a commercial product that is used to treat constipation.
Maltose, as well known as malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. The two glucose molecules in the isomer isomaltose are joined by a (16) bond. Maltose is a two-unit member of the amylose homologous series, which is the primary structural motif of starch. When alpha-amylase degrades starch, it removes two glucose units at a time, resulting in the formation of maltose. This reaction can be seen in germinating seeds, which is why it was named after malt. It is a reducing sugar, as opposed to sucrose.
FAQs
What are examples of oligosaccharides?
Raffinose and stachyose are two examples of common oligosaccharides. It is a trisaccharide composed of three monomers: galactose, glucose, and fructose.
Is oligosaccharide a sugar?
In fact, an oligosaccharide is a saccharide polymer that contains a small number of monosaccharides (typically three to ten) (simple sugars).
Is garlic an oligosaccharide?
Garlic, onion, wheat, and legumes are examples of foods high in oligosaccharides.
