Chitosan

Poliglusam; polyglucosamine; Poly -D-glucosamine; Poly ( D) glucosamine; Deacetylchitin

Biopolymer

Light beige, linear polysaccharide, a Polyaminosaccharid

Lipidadsorber, wound healing

Fixed

Insoluble in water at pH> 6.4

Chitosan (Greek χιτών " petticoat, shell, tanks "), even Poliglusam or poly-D- glucosamine or polyglucosamine is a biopolymer, a naturally occurring Polyaminosaccharid, which is derived from chitin. Like this, it consists of β -1 ,4- glycosidically linked N- acetylglucosamine ( exactly 2 -acetamido- 2-deoxy- β -D - glucopyranose residues). Lying in the overall molecule before more deacetylated 2-amino -2-deoxy - β -D - glucopyranose units, it is called chitosan. Thus, linear molecules, which consist of about 2000 monomers provide. It was discovered in 1859 by C. Rouget by boiling chitin with potassium hydroxide solution.

• 2.1 fat binding
• 2.2 Binding of suspended
• 2.3 Other Features

• 3.1 Material use
• 3.2 nutrition

Origin

Extraction

Chitosan is obtained industrially from chitin by deacetylation. This can be done by ( hot ) caustic soda or enzymatically. Both processes are used technically, in terms of quantity is the alkaline procedure clearly to the fore.

The degree of the resulting deacetylation may vary considerably: the deacetylation can be complete or partial, resulting in a distribution of highly deacetylated can both result in little deacetylated areas or a homogeneous Deacetylierungsverteilung, which has significant effects on the molecular shape. At the same time, due to this chemical procedure, the chain length of the polymer decrease ( depolymerization ), which improves the solubility and the viscosity is reduced. In addition (for example, heavy metals from sodium hydroxide solution) can be introduced for the treatment of foreign atoms. The final products can therefore differ considerably in their properties. Most clearly reveal these differences in solubility and viscosity, for example, a one percent solution of chitosan in acetic acid.

Natural Occurrence

Some mushrooms contain chitin and chitosan in addition to their cell wall; out of them can be directly recovered chitosan. All known species such as Mucor rouxii, Rhizopus oryzae and Absidia coerulea belong to the order Mucorales.

Properties

Chitosan is a colorless, amorphous, viscous substance. Industrially produced, high molecular weight chitosan is soluble in dilute strong acids except sulfuric acid and in organic acids. Solubility in acids and at the same time, poor solubility in a neutral or alkaline pH is unique among the biopolymers and hence characterizing. With decreasing molar mass but also chitosan ( or oligo -glucosamine ) is soluble in water and even in alkaline solutions.

Due to the damages caused by the deacetylation of free amino groups, it is not in alkaline solution, a polycation with a high charge density. It is non-toxic, antibacterial, antiviral and anti-allergenic. The LD50 of chitosan is 16 g / kg body mass.

Fat binding

The fat binding by chitosan can be readily detected in the laboratory. Several patents and laboratory test descriptions for this topic, next are more or less effective products that are based on this principle. The efficiency of the fat binding is quantitatively significant, so chitosan generally in biochemistry and disposal for removing oils, isolated in drug approvals ( eg Spain ) and in medical products with the name of the drug Lipidadsorbens in many countries around the world, including all the member countries EU is unlimited marketable, which have been certified by independent and nationally recognized experts.

The highest fat binding capacity was found in the biopolymer L112 with about 800 times its own weight.

Binding of suspended

Chitosan is used in water treatment, waste water clarification and in the beverage industry varied and on a large scale in order to bind and precipitate suspended particles.

Other Features

• Coagulating, styptic
• Bactericidal, however, different for different bacteria
• Fungicide
• Abrasive ( in toothpaste)
• Smoothing ( additional paper )
• Binding of heavy metals

Applications

Material use

The application spectrum of this polymer is relatively broad and confusing (similar to cellulose and other biopolymers ). Chitosan is mainly used as a filter medium ( water extraction or in sewage treatment plants ) and as a starting material for fibers, foams, membranes, and films ( bioplastics ). Here are some of the beneficial properties in the range of the oxygen - barrier effect, which enables a vacuum seal. A market-related production of bioplastics from chitosan exists, however, not yet.

With its adsorbing, hemostatic, anti - microbial and healing effects of chitosan is also used in medical devices ( eg Lipidadsorbens ( L112 ) or in dressings ) are used. Furthermore, chitosan is used in toothpastes (eg Chitodent ), as paper and cotton as well as the addition of precipitating opacities in the beverage industry. In the pharmaceutical industry has long been researched chitosan, to use it for the microencapsulation and controlled release of pharmacological agents, including as a vector for gene therapy.

Nutrition

In supplements, chitosan is used as a fat blocker, use as a food additive, however, in some countries, including Germany as possibly illegal considered ( in Austria, however, it is legal ), as a food supplement only allowed to supplement the diet, but that does not hinder their absorption. In the countries in which chitosan may be used in the food industry, such as the U.S., several double-blind, randomized studies have shown that its effect without concomitant diet can not be detected.