Names | |
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IUPAC name 6-O-α-D-Galactopyranosyl-D-fructofuranose | |
Other names 6-O-α-D-galactopyranosyl-D-fructose | |
Identifiers | |
3D model (JSmol) | |
ChemSpider | |
PubChem CID | |
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Properties | |
C12H22O11 | |
Molar mass | 342.297 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Melibiulose is a disaccharide formed from fructose and galactose similar to melibiose.
A carbohydrate is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 and thus with the empirical formula Cm(H2O)n, which does not mean the H has covalent bonds with O. However, not all carbohydrates conform to this precise stoichiometric definition, nor are all chemicals that do conform to this definition automatically classified as carbohydrates.
A disaccharide is the sugar formed when two monosaccharides are joined by glycosidic linkage. Like monosaccharides, disaccharides are simple sugars soluble in water. Three common examples are sucrose, lactose, and maltose.
Hydrolysis is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile.
Maltose, also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the two-unit member of the amylose homologous series, the key structural motif of starch. When beta-amylase breaks down starch, it removes two glucose units at a time, producing maltose. An example of this reaction is found in germinating seeds, which is why it was named after malt. Unlike sucrose, it is a reducing sugar.
Maltase is one type of alpha-glucosidase enzymes located in the brush border of the small intestine. This enzyme catalyzes the hydrolysis of disaccharide maltose into two simple sugars of glucose. Maltase is found in plants, bacteria, yeast, humans, and other vertebrates. It is thought to be synthesized by cells of the mucous membrane lining the intestinal wall.
A reducing sugar is any sugar that is capable of acting as a reducing agent. In an alkaline solution, a reducing sugar forms some aldehyde or ketone, which allows it to act as a reducing agent, for example in Benedict's reagent. In such a reaction, the sugar becomes a carboxylic acid.
Glycosaminoglycans (GAGs) or mucopolysaccharides are long, linear polysaccharides consisting of repeating disaccharide units. The repeating two-sugar unit consists of a uronic sugar and an amino sugar, except in the case of the sulfated glycosaminoglycan keratan, where, in place of the uronic sugar there is a galactose unit. GAGs are found in vertebrates, invertebrates and bacteria. Because GAGs are highly polar molecules and attract water; the body uses them as lubricants or shock absorbers.
Lactitol is a disaccharide sugar alcohol produced from lactose. It is used as a replacement bulk sweetener for low calorie foods with 30–40% of the sweetness of sucrose. It is also used medically as a laxative.
Isomalt is a sugar substitute, a mixture of the two disaccharide alcohols 1,6-GPS and 1,1-GPM. It is used primarily for its sugar-like physical properties. It has little to no impact on blood sugar levels, and does not stimulate the release of insulin. It also does not promote tooth decay and is considered to be tooth-friendly. Its energy value is 2 kcal per gram, half that of sugars. It is less sweet than sugar, but can be blended with high-intensity sweeteners such as sucralose to create a mixture with the same sweetness as sucrose (‘sugar’).
Disaccharidases are glycoside hydrolases, enzymes that break down certain types of sugars called disaccharides into simpler sugars called monosaccharides. In the human body, disaccharidases are made mostly in an area of the small intestine's wall called the brush border, making them members of the group of "brush border enzymes".
Keratan sulfate (KS), also called keratosulfate, is any of several sulfated glycosaminoglycans that have been found especially in the cornea, cartilage, and bone. It is also synthesized in the central nervous system where it participates both in development and in the glial scar formation following an injury. Keratan sulfates are large, highly hydrated molecules which in joints can act as a cushion to absorb mechanical shock.
Rutinose is the disaccharide also known as 6-O-α-L-rhamnosyl-D-glucose (C12H22O10) that is present in some flavonoid glycosides. It is prepared from rutin by hydrolysis with the enzyme rhamnodiastase.
Carbohydrate chemistry is a subdiscipline of chemistry primarily concerned with the detection, synthesis, structure, and function of carbohydrates. Due to the general structure of carbohydrates, their synthesis is often preoccupied with the selective formation of glycosidic linkages and the selective reaction of hydroxyl groups; as a result, it relies heavily on the use of protecting groups.
Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed organic matter. It occurs in saprotrophs, and is most often associated with fungi and soil bacteria. Saprotrophic microscopic fungi are sometimes called saprobes; saprotrophic plants or bacterial flora are called saprophytes, although it is now believed that all plants previously thought to be saprotrophic are in fact parasites of microscopic fungi or other plants. The process is most often facilitated through the active transport of such materials through endocytosis within the internal mycelium and its constituent hyphae.
The suffix -ose is used in biochemistry to form the names of sugars. This Latin suffix means "full of", "abounding in", "given to", or "like". Numerous systems exist to name specific sugars more descriptively.
The enzyme protein-glucosylgalactosylhydroxylysine glucosidase (EC 3.2.1.107) catalyzes the following chemical reaction:
Turanose is a reducing disaccharide. The d-isomer is naturally occurring. Its systematic name is α-d-glucopyranosyl-(1→3)-α-d-fructofuranose. It is an analog of sucrose not metabolized by higher plants, but rather acquired through the action of sucrose transporters for intracellular carbohydrate signaling. In addition to its involvement in signal transduction, d-(+)-turanose can also be used as a carbon source by many organisms including numerous species of bacteria and fungi.
Isomaltooligosaccharide (IMO) is a mixture of short-chain carbohydrates which has a digestion-resistant property. IMO is found naturally in some foods, as well as being manufactured commercially. The raw material used for manufacturing IMO is starch, which is enzymatically converted into a mixture of isomaltooligosaccharides.
Unsaturated chondroitin disaccharide hydrolase (EC 3.2.1.180, UGL, unsaturated glucuronyl hydrolase) is an enzyme with systematic name beta-D-4-deoxy-Delta4-GlcAp-(1->3)-beta-D-GalNAc6S hydrolase. This enzyme catalyses the following chemical reaction