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Articles  chemistry

Carbohydrates

Carbohydrates are the pillars of polihidroksi or polihidroksi and ketones include condensate polymer-polimernya formed. The name of carbs used on such compounds, considering its empirical formula of CnH2nOn or approached Cn (H2O) n that is carbon that undergoes hidratasi. Nevertheless this name is actually less precise because hydrates (H2O) attached to carbon cluster is not as hydrate. For example cannot be separated or segregated crystallised regardless of the cluster.

There are a lot of carbs in vegetable material, either in the form of simple sugars, heksosa, pentosa, and carbs with a high molecular weight such as starch, pectin, cellulose, and lignin. Cellulose and lignin acts as a constituent of the cell walls of plants. In General, fruits contain Monosaccharides such as glucose and fructose. 

Disaccharides like cane sugar (sucrose or sakarosa) contained in the stems of sugar cane; in the water there is milk lactose or milk sugar. Several oligosakarida such as dekstrin is found in syrup, starch, bread, and beer. While various polysaccharides such as starch, many found in cereals and tubers; cellulose and pectin is found in many fruits. Biological functions of carbohydrates include, namely:

 1. Starch and glycogen plays an important role as providers of whilst the glucose.

 2. Acts as a structural element and strut in the cell walls of bacteria and plants and tissue binding and cell wall animal organisms.

3. Other Carbohydrates serve as a lubricant joint framework as the compound adhesive between cells, and the giver of the specificity of biology in animal cell surface.

Some chemical properties of carbohydrates:

 Monosaccharides  reduction Properties and some disaccharides have the nature can reduce, especially in a base. Nature as a reducing agent can be used for the purposes of the identification of carbohydrates as well as quantitative analysis. The nature of the reduction is due to the presence of an aldehyde or ketone functional groups in a molecule carbohydrate. Formation of furfural  In a dilute acid solution, although heated Monosaccharides are generally stable. 

But when heated with a concentrated strong acids, Monosaccharides yields of furfural or its derivation. Reaction formation of furfural this is a dehydration reaction or release water molecule of a compound. The formation of a osazon  All carbs have free aldehyde or ketone functional groups will form osazon when heated with excess fenilhidrazin. Osazon happens to have the form of crystals and a typical melting point for each CARB.

 

The formation of ester  the existence of hydroxyl groups in carbohydrates allow occurrence of ester when reacted with acids. Monosaccharides have some cluster – OH and with phosphoric acid may wish to produce esters of phosphoric acid. If isomerization in dilute acid solution