AU768958B2 - Heteroside polymer microgranules of marine origin containing various hydrophilic or hydrophobic substances methods for using same in food, dietetic or pharmaceutical products - Google Patents

Abstract

The invention concerns the use of marine heteroside polymer granules or microgranules containing various hydrophilic or hydrophobic substances in food, dietetic and pharmaceutical products.

Description

HETEROSIDE POLYMER MICROGRANULES OF MARINE ORIGIN CONTAINING VARIOUS HYDROPHILIC OR HYDROPHOBIC SUBSTANCES, METHODS FOR USING SAME FOR NUTRITIONAL, DIETETIC OR PHARMACEUTICAL PURPOSES This invention relates to the use of deacetylated granules or microgranules of chitin or chitosan coating or containing various hydrophilic or lipophilic active principles having a nutritional or therapeutic interest.

We include this invention in the nutritional, dietetic and pharmaceutical field.

Chitin or acetamido-2-deoxy-B-D-Glucose is a polymer entering into the composition of the carapace of arthropods, crustaceans and insects and also the outer membrane of certain fungi. This component makes the rigidity of the endoskeleton of cephalopods possible. It is to the animal kingdom what cellulose is to the plant kingdom.

This substance is rendered inert with respect to numerous substrates through a transformation of its chemical structure, conversion by chemical treatment or N-deacetylation into amino-2-deoxy-B-Glucose or chitosan. This latter substance is easier to use on account of its greater chemical inertness. When the deacetylation is total, regular chitosan or polyglucosamine is obtained. This percentage of deacetylation has an effect on the physical properties of chitosan, solubility and viscosity, and also on its biochemical behavior.

Numerous studies have described the major principles of its mechanisms of action. In its crude flake form, adsorption, and more precisely chemisorption, that is to say the binding of molecules on the surface of the polymer, is well known. It has been demonstrated that the high potentiality of chitosan is the result of a mechanism of absorption in volume, limited by diffusion phenomena. The form of chitosan and the geometry of the material used are then essential. In the crude flake form, the specific surface of chitosan does not exceed a few square centimeters per gram, which singularly limits its significance.

The use of chitosan is interesting in the nutritional and dietetic field because of its very high fiber content, and on the other hand on account of the interesting potential of its structure for forming strong bonds with lipophilic derivatives or other components, but this active principle alone can reach its limits when a significant action with a small amount of substrate is desired or when a progressive effect of this component in time is desired.

In order to limit these negative effects by increasing the binding kinetics of chitosan, various solutions have been proposed, such as grinding, lyophilization of solutions or disruption under pressure, all of these techniques having the objective of increasing the surface-to-mass ratio of the chitosan and concurrently increasing the overall activity of the chitosan.

It seems interesting to make up within these microgranules or granules a chitosan-catalyst complex in order on the one hand to increase the activity of the chitosan and on the other hand to increase the time of activity and the specificity of the activity.

Incorporation of a material with very high specific surface into the web of the chitosan structure will increase its activity not only in terms of binding potentiality but also in terms of kinetics. The incorporation of this catalyst makes it possible to manifestly increase the reaction velocity of the chitosan even if it is present in minute quantity. Thus FR-A-2 700 973 describes microglobules in which chitosan is complexed with carbon black.

Nevertheless the activity of this catalyst-chitosan complex decreases as a function of its water content. A loss of activity results when the system is dried because of condensation of the chitosan on the catalyst. The polymer web that is complexed and dried in this way loses its porosity to the point of expelling all the ionic salts present in the system. In order to avoid these significant problems from the point of view of the activity of the complex, it is necessary to preserve its structure and in particular the hydration and porosity.

In order to increase the activity of the system, it is also possible to create a virtual porosity by doping the complex in the dry state, more preferably with an hygroscopic, non-ionic and water-soluble component. The choice turned to molecules with structures similar to the chitosan polymer, for example, glucose, sucrose or oligofructose.

Once deacetylated, this compound may be used in the form of granules, microgranules or globules, as described, for example, in the patent application FR 2 701 031, "Methods and Devices for the Manufacture of Polymer Globules".

Example 1 Microbeads are obtained from chitosan having a degree of deacetylation of glucose sodium chloride edible carbon black The beads are made from the complex of chitosan and carbon black, the latter substance playing the role of activation catalyst. They are condensed in a dropwise

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fashion, and then saturated with sodium chloride and glucose and dried.

Example 2 The microbeads are obtained from chitosan having a degree of deacetylation of sodium phosphate carbon black The beads are made from the complex of chitosan and carbon black, the latter substance playing the role of activation catalyst. They are condensed in a dropwise fashion, and then saturated with sodium phosphate'and dried.

Example 3 The microbeads are obtained from -55% chitosan, having a degree of deacetylation of 20 -42% fructose of an iron salt The beads are made from the complex of chitosan and the iron salt, the latter substance playing the role of activation catalyst. They are condensed in a dropwise fashion, and then saturated with fructose and dried.

Example 4 The microbeads are obtained from chitosan, having a degree of deacetylation of -42% oligofructose sugars having well-established nutritional characteristics -10% coffee extracts edible carbon black The beads are made from the complex of chitosan and carbon black, the latter substance playing the role of activation catalyst. They are condensed in a dropwise fashion, and then saturated with oligosaccharides and coffee extracts and dried. The microbeads in this way offer all of the guarantees of quality and reproducibility that are difficult to obtain from natural products.

The microgranules, which may also be designated beads, microbeads or microglobules, are formed from chitosan and from hydrophobic or non-hydrophobic substances, at least one of these substances playing the role of catalytic substance, in this way forming a complex with the chitosan. The microgranules formed in this way have a strong attraction for all substances and in particular for oleaginous substances. According to the first results of clinical studies, use of these microgranules by numerous subjects shows a clear reduction in the weight of these subjects as well as a consequent remodeling of the physical appearance. These two actions are explained by the limitation of lipid absorption as a result of complexes formed between microgranules and oleaginous substances. Other trials that have been carried out show that the use of these microgranules entails a high potentiality for complex formation with substances originating from heavy metals, in this way limiting the absorption of these microparticles by the organism. Through a mechanism of exchange and capture, the formation of microgranules of chitosan complexed with certain substances makes possible the limitation of the formation of the molecules which are designated free radicals, which come into play in many biological reactions.

Claims (8)

1.Microgranules made up of a complex of chitosan or a chitosan derivative and a material with a very high specific surface of the sort to increase the kinetics of binding of the chitosan with lipophilic derivatives or other components, characterized in that said material with a very high specific surface is edible carbon black and characterized in that the microgranules include moreover an hygroscopic, non-ionic and water-soluble component, with a structure similar to chitosan, said hygroscopic component relating to the preservation of the structure and in particular the hydration and porosity of said chitosan-carbon black complex.

2.Microgranules according to claim 1, characterized in that said hygroscopic component is chosen from among the group made up of glucose, saccharose or oligofructose.

3.Microgranules according to claim 1 or 2, characterized in that said chitosan has a degree of deacetylation of 4 9

4.Microgranules according to anyone of claims 1 to 3, characterized in that they also include an extract of coffee. according to anyone of claims 1 to 3, characterized in that they also include sodium chloride.

6.Method of manufacture of microgranules according to anyone of claims 1 to 5, characterized in that it includes steps consistent with condensing said chitosan- carbon black complex in a dropwise fashion and then saturating said complex with said hygroscopic component and drying the whole of it.

7.Use of microgranules according to anyone of claims 1 to 5 to complex oleaginous substances.

8.Use of microgranules according to anyone of claims 1 to 5 to complex heavy metals.

9.Use of microgranules according to anyone of claims 1 to 5 to limit the formation of free radicals.