Definition of disacarids - What is it, Meaning and Concept

A disacarido -term that comes from the English word disaccharide -is a carbohydrate that is composed of two monosaccharides .This definition, as you can see, requires us to know what carbohydrates are and what monosaccharides are to understand the notion of disacarido.

Carbohydrates, also called carbohydrates or carbohydrates , are organic substances composed of oxygen, hydrogen and carbon .The first two elements mentioned appear in proportion of two to one.The function of carbohydrates is to promote energy collection and storage, especially for use in the brain and nervous system.An enzyme called amylase allows its molecule to break down and can be used as fuel for our body.

A monosaccharide , on the other hand, is a sugar cuy A decomposition into a simpler one through hydrolysis (molecular splitting through water) is not possible.It is also known as simple sugar and has between three and seven carbon atoms, and this Quantity is crucial when naming it.The suffix used in its nomenclature is -osa , as can be seen in the case of glucose , the most important source of energy for cells.

The disacarids, in short, are carbohydrates whose composition has two sugars that are part of the group of monosaccharides.There are several disacarids according to their components and the type of union that links them.

The lactose , for example, is the disacarid formed by the union of the monosaccharides galactose and fructose .This disacarid is found in the milk produced by mammalian animals.People whose body fails to assimilate the disacarid in question adequately suffer from the disorder known as lactose intolerance .

Another very common disacarid is the sucrose , composed of monosaccharide molecules glucose and fructose .Sucrose is the product we know as table sugar or common sugar , which is used daily almost everywhere, since it is the most popular sweetener, used to sweeten all kinds of foods and drinks.

In more technical terms, we can say that sucrose is made up of alpha-glucopyranoside and beta-fructofuranose, which can be seen in its chemical name, alpha-D-Glucopyranosyl-(1 → 2)-beta-D-Fructofuranoside .These two monosaccharides that form it are joined through a O-glucosidic type bond, which is also dicarbonyl, since the alpha bond is made up of the two carbons The linkers are hydrolyzed by the enzyme called sucrose or invertase (this last name is due to the fact that hydrolyzed sucrose is an inverted sugar).Its chemical formula , on the other hand, is C12H22O11 .

This disacarido cannot act as a reducer on the reagents of Fehling (a solution discovered in 1849 that is used to determine reducing sugars) and Tollens (an aqueous complex that is usually presented as nitrate and used to detect aldehydes in qualitative tests).

With respect to the physical characteristics of this disacarido, its crystal is transparent and when the light causes a diffraction multiple in a set of crystals it is perceived as white.

Returning to its function to sweeten food, sucrose can be found both in the so-called sugar cane , of which it represents 20% of its total weight , and in the sugar beet , in an approximate proportion of 15% of its weight.In honey we can also find a significant amount of sucrose.

It should be noted that some disacarids are composed of two molecules of the same monosaccharide.This occurs with the cellobiose , the maltose and the trehalose , which are formed with the union of glucose molecules according to different kinds of links.