AU2007242781B2 - Use of fungal polysaccharides as pharmaceutical composition or food complements - Google Patents

Abstract

The invention concerns the use of at least one fungal polysaccharide comprising for the major part a chitin-glucan copolymer, for making an orally administered composition. In particular, the invention concerns a pharmaceutical composition or food complements for preventing, treating or controlling in particular dyslipidemia, hypercholesterolemia, atherosclerosis, and for stimulating antioxidant activities of the organism to stimulate the immune system, perform a hypoglycemic action beneficial in the case of diabetes, and promoting satiety to minimise the metabolic syndrome.

Description

1 Use of polysaccharides of fungal origin as a pharmaceutical composition or food supplements. The invention relates to the use of polysaccharides of fungal origin 5 as a pharmaceutical composition or food supplements for human and animal health. Prior ar 10 It is known that both microscopic and edible fungi have properties that are beneficial to the health, such as hypoglycaemic, blood-cholesterol lowering, antioxidant or immunostimulant properties. Fungi contain digestible compounds that have important properties with respect to the health of the gastrointestinal tract and of the body in general, and are 15 defined as being polysaccharide-type dietary fibre. They have the property of acting on glucose circulation by lowering the blood insulin concentration, increasing the viscosity of foods in the small intestine and slowing down carbohydrate absorption. They therefore have the ability to regulate sugar metabolism. They also play a role in the regulation of 20 arterial blood pressure. Fungi which contain large amounts of fibre have a beneficial effect on reducing the concentration of total cholesterol, and of HDL-cholesterol in the blood, as shown by a study by Fukushima et al., (2000) fibre from the mushroom Agaricus bisporus (Fukushima M, Nakano M, Morii Y, Ohashi T, Fujiwara Y & Sonoyama K (2000) J. Nutr. 130:2151). 25 They therefore play an indirect role in the prevention of hypertension and of cardiovascular diseases and, more largely, on obesity and metabolic syndrome. Very few foods exert immunostimulant properties. Most food products induce immunodepression rather than immunostimulation. Fungi 2 such as the shiitake mushroom (Lentinus edodes), the maitake mushroom (Grifola frondosa), the reishi mushroom (Ganoderma lucidum) or the ABM mushroom (Agaricus blaze mur/) are "immunostimulant" foods. The immunostimulant function is largely attributed to the presence of beta 5 glucan type polysaccharides present in their cell walls (Lull C, Wichers HJ & Savelkoul HFJ (2005) Antlinflammatory and immunomodulating properties of fungal metabolites. Mediators Inflammation 2:63). Certain plant fibre is recommended for preventing, inhibiting or treating obesity and obesity-related diseases, for instance oligofructoses 10 derived from chicory inulin, or laminarin, a beta-glucan derived from algae. Oligofructoses act by fermenting in the colon, thus releasing compounds capable of suppressing the plasma content of ghrelin, a hormone that usually stimulates the appetite. Indirectly, by increasing satiety and reducing food intake, an effect on cholesterol level and 15 atherosclerosis is observed, among the numerous effects associated with metabolism syndrome and with cardiovascular diseases. Chitosan, a polysaccharide conventionally derived from chitin from the shells of shellfish and considered to be a fibre, is also known to exert a blood-lipid-lowering and blood-cholesterol-lowering action. These effects 20 are attributed to a mechanism of interaction between the dietary fatty acids in the stomach or the bile acids (negatively charged), and chitosan, which is positively charged. However, chitosan has the drawback that its source is shellfish, which is potentially allergenic . 25 Non-food-related uses of compositions containing the chitin-glucan copolymer are known, in particular as an active agent for healing the skin. The mycoton and mycoran compositions derived from Aspergillus niger are described for their properties when applied to the skin and to scars.

3 However, no oral application is known, in particular in the dietary or pharmaceutical field. Most of the studies carried out on the beneficial effects of fibre of fungal origin were done so either on fresh fungi, or on powdered fungi, or 5 on beta-glucans that are soluble in an aqueous medium, generally extracted from plants. These products are not, however, the most suitable for the above-mentioned indications. It would be advantageous if at least preferred embodiments of the invention provide a family of natural substances of fungal origin that makes 10 it possible to provide a food supplement or a pharmaceutical composition, in particular for improving human and animal health as a supplement to a balanced diet and good hygiene practice, in particular in the prevention and/or combating of pathologies such as metabolic syndrome, obesity, diabetes and cardiovascular diseases, or related diseases. 15 It would also be advantageous if at least preferred embodiments of the present invention provide a family of substances that inhibits impeccable food safety, while at the same time being readily available in large volume at a cost compatible with use as food supplements. It would also be advantageous if at least preferred embodiments of 20 the invention provide a family of natural substances of nonanimal origin and of excellent purity, that are well characterized and with good traceability. It would also be advantageous if at least preferred embodiments of the present invention provide a food supplement, of polysaccharide type, that is stable and easy to formulate. 25 It would also be advantageous if at least preferred embodiments of the invention provide a pharmaceutical active agent or food supplement that makes it possible to return the parameters associated with the metabolic syndrome, obesity, diabetes and/or 4 cardiovascular disease pathologies to the normal level, such as, by way of example, the triglyceride content, the balance between LDL-cholesterol and HDL-cholesterol, the surface area of the aortic arch covered with lipid deposits, the antioxidant capacity of plasma, etc. 5 Description of the invention The present invention provides the following items 1 to 18: 1. Use of at least one polysaccharide of fungal origin comprising predominantly a chitin-glucan copolymer, for the manufacture of a 10 composition administered orally to a human being or an animal, for obtaining an effect chosen from the group consisting of an antioxidant, blood cholesterol-lowering or blood-lipid-lowering effect, a stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating 15 and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia. 2. Method for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a 20 stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting In preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and 25 hyperuricemia, comprising administering orally to a human being or an animal an effective amount of a composition comprising at least one polysaccharide of fungal origin comprising predominantly a chitin-glucan copolymer. 3871286.1 (GHM9Uers) PT9261.AU 4a 3. Use according to item 1 or method according to item 2, wherein the hypoglycaemic effect is obtained in a human or animal having diabetes. 4. Use or method according to any one of items 1 to 3, wherein the animal is a non-human mammal. 5 5. Use of at least one polysaccharide of fungal origin that is insoluble in an aqueous or organic medium, said polysaccharide comprising predominantly a chitin-glucan copolymer, for the manufacture of a composition administered orally, as antioxidant, blood-cholesterol-lowering or blood-lipid-lowering composition, for stimulating the immune system, 10 for a hypoglycaemic effect, for a satiety effect, for improving food transit, or for preventing, or treating, or combating a pathology selected from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes, and hyperuricemia. 15 6. Method for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating and/or combating a pathology 20 chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia, comprising administering orally an effective amount of a composition comprising at least one polysaccharide of fungal origin that is insoluble in an aqueous or organic medium, said 25 polysaccharide comprising predominantly a chitin-glucan copolymer.

4b 7. Use or method according to any one of items 1 to 4, wherein said chitin-glucan copolymer comprises a ratio of chitin to beta-glucans of between 70:30 and 20:80. 8. Use of at least one extract of fungal origin containing essentially a 5 polysaccharide as defined in any one of the preceding items, for the manufacture of a composition administered orally, as antioxidant, blood-cholesterol-lowering or blood-lipid-lowering composition, for stimulating the immune system, for a hypoglycaemic effect, for a satiety effect, for improving food transit, or for preventing, or treating, or 10 combating a pathology selected from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes, and hyperuricemia. 9. Method for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a 15 stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, 20 diabetes and hyperuricemia, comprising administering orally an effective amount of a composition comprising at least one extract of fungal origin containing essentially a polysaccharide as defined in any one of the preceding items. 10. Use according to item 8 or method according to item 9, characterized 25 in that the polysaccharide comprises more than 70% of chitin-glucan polysaccharides by mass relative to the total mass of the extract of fungal origin.

4c 11. Use or method according to item 10, characterized in that the polysaccharide comprises greater than 85% of chitin-glucan polysaccharides by mass relative to the total mass of the extract of fungal origin. 5 12. Use or method according to any one of the preceding items, characterized in that Aspergi/us niger is used as fungal origin. 13. Use or method according to any one of the preceding Items, characterized in that a hydrolysate of the polysaccharide defined in any one of the preceding items is used. 10 14. Use or method according to item 13, characterized in that the chitin glucan hydrolysate has a ratio of chitin to beta-glucans of between 60:40 and 15:85 (m/m). 15. Use or method according to any one of the preceding items, characterized in that at least 85% of the chitin part of the chitin-glucan 15 copolymer is N-acetyl-D-glucosamine units, and that at most 15% is D glucosamine units. 16. Use or method according to any one of the preceding items, characterized in that the composition is intended for an effect blood cholesterol-lowering or blood-lipid-lowering effect. 20 17, An oral pharmaceutical formulation comprising a pharmaceutically effective amount of at least one extract of fungal origin comprising predominantly a chitin-glucan copolymer or hydrolysate thereof and pharmaceutically orally acceptable excipients and optionally other active ingredients, said chitin-glucan copolymer or hydrolysate thereof 25 comprising a mass ratio (m/m) of chitin to beta-glucans of between 50:50 and 10:90, 455128& IGHMattWR) P7928 IAU 4d when used for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a stimulatory effect on the Immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect 5 consisting in preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia. 18. A food composition comprising at least one extract of fungal origin 10 comprising predominantly a chitin-glucan copolymer or hydrolysate thereof, said chitin-glucan copolymer or hydrolysate thereof comprising a mass ratio (m/m) of chitin to beta-glucans of between 50:50 and 10:90, when used for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, 15 a stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, 20 diabetes and hyperuricemia. The present invention describes the effect of the extract, advantageously purified, of a fungal source, and preferably of AspergIlus niger. The hydrolysates of the purified extracts, i.e. the copolymers of chitin and of beta-glucan of lower molecular mass, are also part of the 25 invention. It is the association between the two polymers (chitin and beta glucan) and the three-dimensional architecture of the copolymer derived form the fungal source which makes it a compound beneficial to the health. The availability and the quality in particular of Aspergil/us niger, 4731313_1 (GMMatters) P79251 AU 4e which is a coproduct of the production of citric acid intended for the food and pharmaceutical industry, make it a starting material of choice for uses of its derivatives, in human and animal health. Fibre of polysaccharide type and oligomers thereof of various 5 origins are also known for their beneficial actions, such as oligofructoses, laminarin or chitosan. The present inventors had already described a process for producing chitosan of nonanimal origin, from fungal sources, and more particularly from a fungus of AspergIlus niger type, in international application WO 03/068824. 10 Now, the inventors have discovered, surprisingly that the chitIn glucan compound derived from the fungal sources mentioned above, and in particular from the fungus Aspergillus niger, and Its hydrolysates, surprisingly combine several of the known properties of fibre, and that the chitosan is not the compound most indicated for overcoming 15 4731313_1 (GHFalters) P79251.AU 5 dyslipidemias, for example. In fact, the chitin-glucan compound and its hydrolysates exert both blood-cholesterol-lowering and hypoglycaemic effects, they increase the antioxidant capacity of plasma, thus promoting a decrease in atheroma plaque, they promote satiety and stimulate the 5 immune system. As regards chitosan, it seems to be the case, a priori, that its slimming action is exerted by virtue of its ability to bind lipids at the gastric level, and that its blood-cholesterol-lowering action is exerted by virtue of its ability to bind lipids at the intestinal level, via electrostatic 10 interactions between fatty acids or bile acids and the ammonium groups of chitosan. Now, the chitin-glucan substances and hydrolysates thereof of the invention, firstly, essentially exert no electrostatic charge and, secondly, are not capable of taking up fatty acids in vitro. Nevertheless, they inhibit a significant reducing action on triglyceride content, on total 15 cholesterol content and on LDL-cholesterol, which is equivalent to that of chitosan, while at the same time promoting an increase in HDL-cholesterol in a manner equivalent to that of chitosan. Added to these common actions are effects that are not described with chitosan, which make them advantageous substances: chitin-glucan 20 and its hydrolysates are capable of absorbing generally approximately 10 times their mass in water, which makes them substances with good fibre properties capable in particular of improving transit. They are capable of significantly stimulating plasma antioxidant activity and of exercising an immunostimulant activity due to the synergy between the chitin part and 25 the beta-glucan part. Since they are not capable of taking up lipids at the gastric level, the chitin-glucan and its hydrolysates do not bring about risks of lipophilic nutrient (vitamin) imbalance, as is sometimes suspected for chitosan. Finally, the chitin-glucan and its hydrolysates are obtained and purified 6 according to a process that is readily carried out, starting from fungal sources of excellent quality, which are coproducts that are available in large amount and renewable, and which are not of animal origin. The inventors mean, by "polysaccharides of fungal origin", the 5 extracts purified from fungal cell walls composed predominantly of polysaccharides of chitin and of beta-glucan, in the form of copolymers, and hydrolysates thereof. The purified extracts preferably comprise a chitin-glucan content of greater than 70% by mass relative to the total mass of the extract, preferably greater than 80%, preferably greater than 10 85%, and more preferably greater than 95%. The inventors mean, by "chitin-glucan", a pure copolymer extracted from fungal cell walls which consist of links of N-acetyl-D-glucosamine units and, optionally, of a minor proportion of D-glucosamine units linked to one another by (1,6)-type linkages in the alpha conformation (chitin 15 link), and of links of D-glucose units linked to one another by (1,3)-type, (1,3)(1,6)-type or (1,3)(1,4)-type linkages, and preferably (1,3)-type linkages, in the beta conformation (beta-glucan link, also referred to herein as "glucan"). It is generally accepted that fungal cell wall polysaccharides can be 20 separated into two groups according to their solubility in an alkali medium, and that the cell wall backbone is insoluble. It is also known that the insoluble fraction consists of chitin and of beta-glucans, in variable proportions according to the species, that the beta-glucan units are linked by links of variable structure, and that the linkage between the chitin and 25 beta-glucans is stable, as shown, for example, by Siestma & Wessels for Saccharomyces cerevisiae (Zygomycete), Neurospora crassa (Ascomycete), Aspergi/us nidulans (Ascomycete) and Coprinus cinereus (Basidiomycete) (Siestma JH & Wessels JG. (1981) Solubility of (1,3)-beta D-(1,6)-beta-D-glucan in fungal walls: importance of presumed linkage 7 between glucan and chitin. (1981) J. Gen. Microbiol. 125:209). It is known that the chitin and beta-glucan links of the insoluble fraction of Aspergi//us niger are linked to one another covalently, as mentioned, for example, by Stagg CM and Feather MS (Biochim. Biophys. (1973) Acta 320:64). 5 Methods for determining the nature of the covalent linkage between the chitin and the beta-glucans have been described, for example, by Fontaine et al., for Aspergi/us fumigatus (Fontaine T, Simenel C, Dubreucq G, Adam 0, Delepierre M, Lemoine J, Vorgias CE, Diaquin M & Latge JP. (2000) Molecular organization of the alkali-insoluble fraction of Aspergi//us 10 fumigatus cell wall, J. Bio. Chem. 275:27594), and by Kollar et al., for the yeast Saccharomyces cerevisiae (Kollar R, Petrakovas E, Ashwell G, Robbins P & Cabib E. (1995) Architecture of the yeast cell wall, the linkage between chitin and beta(1,3)glucan, J. Biol. Chem. 270:1170). Advantageously, the chitin-glucan copolymer contains less than 10 15 % of water-soluble compounds. Preferably, the chitin-glucan copolymer has purity higher than 80 %, and preferably higher than 85 %. Advantageously, the chitin-glucan copolymer contains less than 40 mg/kg of heavy metals, and preferably less than 20 mg/kg of heavy metals, as determined by the method described in the 2.4.8F monography of the 20 European Pharmacopeia. Advantageously, the chitin-glucan copolymer contains less than 2 ppm of arsenic, as determined by AES-ICP. Advantageously, the chitin-glucan copolymer has a microbiogical quality suited to food-related applications, preferably less than 10,000 cfu/g for both total microbial count and yeast and molds, more preferably less than 25 1,000 cfu/g. The ratio of chitin to beta-glucan may be between 95:5 and 5:95, preferably between 70:30 and 20:80, and more preferably between 70:30 and 25:75, and more preferably between 60:40 and 25:75 (m/m). Another preferred ratio of chitin to beta-glucan is comprised between 50:50 and 8 10:90, preferably between 45:55 and 20:80. This type of copolymer may be obtained by hydrolysis of chitin-glucan copolymer described previously. The chitin part of the chitin-glucan copolymer is preferably composed of at least 85% of N-acetyl-D-glucosamine units and of at most 15% of 5 D-glucosamine units, preferably of at least 90% of N-acetyl-D glucosamine units and at most 10% of D-glucosamine units. The copolymer is generally in the form of a white to slightly brown powder. It is essentially insoluble in aqueous and organic solvents irrespective of the temperature and the pH. It is capable of swelling in aqueous media. It is 10 hygroscopic, and can generally absorb approximately 7 times its mass in water, which corresponds to the swelling capacity of vegetal insoluble fibres such as hemicellulose or pectine. Advantageously, the chitin-glucan copolymers according to the 15 present invention are obtained by means of the process described in international application WO 03/068824 and French patent application FR 0507066 filed in the name of KITOZYME S.A. respectively on 12 February 2003 and 4 July 2005, which are entirely incorporated herein by way of reference. This process is described in particular in application 20 FR 0507066, pages 18, line 14, et seq., of the application as filed. Aspergillus niger is preferably used as fungal source in this process. Advantageously this method is comprising the following subsequent steps: 1) Optionally suspending the biomass in an acidic solution and 25 remove the acid soluble product, 2) Suspending the acid-insoluble fraction in an alkaline solution and removing the alkali-soluble product, 3) Purifying the alkali-insoluble product by further treatment with water, 9 4) Drying the water-insoluble product 5) Optionally purifying the dried product by treatment in organic solvent, 6) Optionally drying the organic-insoluble product. 5 The first step of suspending the biomass in an acidic solution is optional, depending on the initial biomass composition and on the purity required for the final chitin-glucan copolymer product. The acidic solution is preferably an aqueous solution of chlorhydric acid or sulfuric acid, and 10 preferably chlorhydric acid. Preferably said acidic solution has a concentration comprised 0.1 and 5 N, and preferably of about 0.5N. This first extraction step allows eliminating acidic-soluble compounds, including inorganic compounds. The second step makes use preferably of an aqueous solution of an 15 alkali like sodium hydroxide, potassium hydroxide, ammonium hydroxide, and preferably sodium of potassium hydroxide. Preferably, said basic solution has a concentration comprised between 0.1 and 5 N, and preferably of about 0.5N. The third step of purifying the alkali-insoluble product is preferably 20 performed by contacting said product with water and separating the water-insoluble product for example by filtration. Each step may be performed at a temperature preferably ranging between 5 and 120 0 C, and more preferably at a temperature lower than 60 0 C. The biomass is preferably ranging between 1 and 15% (dry weight, 25 w/v), and more preferably 3 and 12%. These steps are each lasting preferably between 4 and 48 hours, and more preferably less than 30 hours. Each step can be repeated several times. The inventors mean, by "chitin-glucan hydrolysates", the copolymers resulting from the controlled hydrolysis of the, chitin-glucan 10 copolymer extracted in particular from fungal cell walls, which also consist of covalently linked chitin links and beta-glucan links, with the ratio of chitin to beta-glucan preferably being between 50:50 and 10:90 (m/m), preferably between 60:40 and 15:85 (m/m). The hydrolysates have a 5 molecular mass that is less than that of the chitin-glucan copolymer, resulting from partial hydrolysis. The chitin part of the chitin-glucan hydrolysates is preferably composed of at least 85% of N-acetyl-D-glucos amine units and of at most 15% of D-glucosamine units, preferably at least 90% of N-acetyl-D-glucosamine units and at most 10% of 10 D-glucosamine units. Detailed description of the invention The inventors have discovered, surprisingly, that a chitin-glucan 15 copolymer and its hydrolysates, belonging to a family of polysaccharides having a structure similar to that of chitosan, has blood-cholesterol lowering properties equivalent to that of chitosan, although it is not essentially charged. This compound is readily obtained starting from fungal sources, for instance the mycelium of Aspergi/us n/ger, of which it 20 constitutes the insoluble part of the cell wall exoskeleton. The chitin glucan copolymer and its hydrolysates also have other effects that are beneficial to the health, described in the present invention. The invention relates in particular to the use of polysaccharides extracted from fungal sources and their hydrolysed derivatives, as 25 pharmaceutical active agents or food supplements for improving human and animal health. Regular oral administration of the polysaccharides of the invention makes it possible in particular to prevent, treat or combat, especially, dyslipidemia, hypercholesterolemia and atherosclerosis, and to stimulate the antioxidant activities of the organism, to stimulate the 11 immune system, to exert a hypoglycaemic action that is favourable in the case of diabetes, and to promote satiety so as to minimize metabolic syndrome. The polysaccharides of the invention are obtained from fungal sources according to an advantageous process that allows excellent purity and good reproducibility, 5 with a large production capacity. The polysaccharides of the invention consist essentially of D-glucosamine units, and/or N-acetyl-D-glucosamine units and D-glucose units, in particular polymers of chitin (N-acetyl-D-glucosamine) and beta-glucan (D-glucose). The present invention also comprises any modifications of the polymer or copolymer, for example by grafting chemical 10 functions onto the polymer, so as to improve the properties thereof. Thus, according to a first aspect, the present invention relates to the use of at least one polysaccharide of fungal origin comprising predominantly a chitin-glucan copolymer, for the manufacture of a composition administered orally, as described above under "Description of the invention". 15 The present invention also relates to the use of at least one polysaccharide of fungal origin that is insoluble in an aqueous or organic medium, said polysaccharide comprising predominantly a chitin-glucan copolymer, for the manufacture of a composition administered orally, as described above under "Description of the invention". 20 Also described herein is the use of at least one polysaccharide of fungal origin comprising a polymer comprising beta-glucan linkages, said beta-glucan linkages consisting essentially of beta-glucan linkages in the 1,3-position, for the manufacture of a composition administered orally. The present invention also relates to the use of at least one extract of 25 fungal origin containing essentially a polysaccharide as defined above, for the manufacture of a composition administered orally, as described above under "Description of the invention". Advantageously, the polysaccharide comprises more than 70% of chitin-glucan 12 polysaccharides by mass relative to the total mass of the extract of fungal origin, preferably greater than 85%. The fungal extract can be obtained from mycelium cell walls of fungi of various groups, including Zygomycetes, Basidiomycetes, 5 Ascomycetes (of which Aspergilus niger is part) and Deuteromycetes, and/or a mixture thereof. Said fungal source should be chosen so as to allow the extraction of a polysaccharide as defined above and hereinafter. Sources of fungi which comprise glucans exist, but these units are water soluble in particular, or comprise little or no chains of chitin structure, and 10 do not therefore make it possible to obtain the polysaccharide of the present invention. The fungal source may be natural or genetically modified (GMO). The present invention covers all type of fungi allowing recovering chitin-glucan polymer as defined in the present invention. 15 Advantageously, a hydrolysate of the polysaccharide defined is used. Advantageously, the chitin-glucan hydrolysate has a ratio of chitin to beta-glucans of between 60:40 and 15:85 (m/m). Advantageously, at least 85 % of the chitin part of the chitin-glucan 20 copolymer is N-acetyl-D-glucosamine units, and at most 15% of this part is D-glucosamine units. Thus, the invention makes it possible to provide a composition administered orally to a human being or an animal, preferably a mammal, for obtaining an effect chosen from the group consisting of an antioxidant, 25 blood-cholesterol-lowering or blood-lipid-lowering effect, a stimulating effect on the immune system, a hypoglycaemic effect, in particular in the case of diabetes, a satiety effect, an effect which improves food transit, 13 and an effect consisting in preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia. 5 The invention also relates to an oral pharmaceutical formulation or food composition comprising, as active ingredient, at least one extract of fungal origin, as defined above. The present invention also relates to a method of treating, preventing or combating a pathology, in particular that mentioned above, 10. comprising the oral administration of an effective amount of a composition comprising at least one polysaccharide as defined in the description above and hereinafter, to an individual needing the latter. The present Invention also relates to a method for lowering the weight or preventing of fighting against the weight uptake of a human 15 being or an animal, and preferably a mammal. This method notably relates to an aesthetic care. The present invention also relates to a method for promoting the food tract. Thus, the present invention relates to the use of a product of the 20 present invention for the manufacture of a composition aimed notably to be used in one of the method here above described or to perform one of the effects described here before or herein after. Those skilled in the art can readily determine, by conventional methods, the effective amounts of the products of the invention to be 25 used. An effective amount of between 0.001% and 100% by weight of the products according to the present invention, relative to the total weight of the composition to be administered, is advantageously used. If the products are administered in the form of gelatine capsules, granules, or tablets, they can be used pure or at any other concentration, accompanied 13a by other active components or by excipients. If they are incorporated into foods, the concentration of product is less than 15%, and preferably less than 10%. The products of the invention are generally formulated in the form 5 of granules, tablets or gelatine capsules, or else incorporated into foods or into drinks. In the figures: 14 Figure 1 represents the conditions for recording the solid-phase carbon 13 nuclear magnetic resonance (13C-NMR) spectrum of chitin glucan F1 and hydrolysed chitin-glucan F4. Figure 2 represents the 13C-NMR spectrum of chitin-glucan F1 5 (batch 28). Figure 3 represents the 13C-NMR spectrum of the hydrolysed chitin-glucan F4 (batch 2). Other characteristics and advantages of the invention 10 will emerge more clearly to those skilled in the art upon reading the explanatory description which refers to examples that are given only by way of illustration and cannot in any way limit the scope of the invention. The examples are an integral part of the present invention and any characteristic that appears to be new in relation to any prior art based on 15 the description taken in its entirety, including the examples, is an integral part of the invention in terms of its function and in terms of its generality. Thus, each example has a general scope. Furthermore, in the examples, all the percentages are given by weight, unless otherwise indicated, and the temperature is expressed in 20 degrees Celsius unless otherwise indicated, and the pressure is atmospheric pressure unless otherwise indicated. Examples 25 The process for obtaining the chitin-glucan copolymers obtained below is described in patent applications WO 03/068824 and FR 05.07066. EXAMPLE 1- Examples of chitin-glucan copolymers extracted and purified from the mycelium of Aspergil/us niger (extract F1) 15 To prepare the F1 chitin-glucan copolymer, a mass of 50 kg (dry weight) of wet Aspergil/us niger mycelium is suspended in a solution of hydrochloric acid at a concentration of 1%, and then filtered. The solid 5 matter is subsequently suspended in a solution of sodium hydroxide at 0.25%, and then filtered. The solid matter is washed 4 times with water and then dried. It is subsequently suspended in ethanol, and then filtered and dried. Approximately 20 kg of chitin-glucan (Fl) are obtained. The molecular characteristics and the composition of six batches of F1 10 chitin-glucan are given in Table 1. The chitin/glucan mass ratio is calculated from the solid-phase carbon 13 nuclear magnetic resonance (MNR) spectrum recorded under the conditions indicated in Figure 1 according to the method briefly described below. The spectrum of the F1 chitin-glucan compound (batch 28) is 15 shown in Figure 2. The proportion of beta-glucan is determined from the area of the following four resonance bands: 104 ppm (carbon 1 of the chitin and of the beta-glucan), 23 ppm (CH 3 carbon of the chitin), 55 ppm (carbon 2 of the chitin) and 61 ppm (carbon 6 of the chitin and of the beta-glucan), taking pure chitin as reference. For example, the calculation 20 can be carried out according to formula 1, where I' is the area of the signals of the carbons, and where [ ]cG indicates the value of the ratio for the chitin-glucan analysed and [ ]c the value for the reference chitin. C1 is carbon 1 of the chitin and of the beta-glucan and C2 is carbon 2 of the chitin. 25 S I'(C1) I'(C Glucan (mol%) = I'(C2) G -I'(2] x100 (1) I'(C2) 1CG 16 The chitin/glucan mass ratio of the six chitin-glucan batches is on average 39:61 ± 2 (m/m). The proportion of D-glucosamine (NGIc) units, expressed as mol% of the chitin part, can be estimated from the NMR spectrum, as described by 5 Heux et al., (Heux L, Brugnerotto J, Desbrieres J, Versali MF & Rinaudo M. (2000) Solid state NMR for determination of the degree of acetylation of chitin and chitosan. Biomacromolecules 1:746). The proportion of D glucosamine units is determined by potentiometric titration with sodium hydroxide, in suspension in an excess of hydrochloric acid. 10 The microbiological quality of the chitin-glucan and the results of searching for pathogenic agents are given in Table 2.

17 Table 1- Molecular characteristics and composition of various batches of the chitin-glucan copolymer (F1) NG1c Batd Chitin-glucan ratio Ash Proteins Upids Heavy metals (m/m) Mol% (%) (%) (%) (ppm) F1 batch 26 36:64 & 5* 0 0.4 4.63 0 < LQ** F1 batch 27 42:58 * 7 0 1.3 3.54 0 < LQ F1 batch 28 39:61 * 7 0 1.5 2.51 2.09 < LQ F1 batch 29 40:60 * 6 0 1.7 3.05 0.06 < LQ F1 batch 30 37:63 * 1 0 1. 9 1.54 1.24 8.7 F1 batch 31 40:60 t 4 0 2.5 4.26 1.27 < LQ * standard deviation over the result of 4 calculations of the chitin-glucan 5 ratio; **LQ. lmit of sensitivity of the ion coupled plasma method of analysis (5.3 ppm) Table 2- Microbiological quality of the F1 chitin-glucan (batch 26) Number of microorganisms/g Total mesophilic aerobic 20 c microorganisms u/g Aerobic spores < 10 cfu/g Yeasts and moulds 20 cfu/g Pathogenic agents Enterobacteriaceae < 10 cfu/g Eschen'chia coli < 10 cfu/g Staphylococcus coagulase+ < 10 cfu/g Pseudomonas spp 10 cfu/g Salmonella spp Absence 10 It is thus understood from the above tables that the copolymer according to the present invention has a high degree of purity.

EXAMPLE 2- Examples of hydrolysates of the chitin-glucan copolymer (F4) In this example, the F4 chitin-glucan hydrolysates are obtained by basic 5 hydrolysis of the F1 chitin-glucan copolymer at 100 0 C or above, for at least 2 hours, in a solution of sodium hydroxide at a concentration of greater than 30%. The matter is washed with water several times, suspended in ethanol, and then filtered and dried. Approximately 5 kg of hydrolysate are obtained, starting from 20 kg of F1 chitin-glucan. 10 The molecular characteristics and the composition of some batches of F4 chitin-glucan hydrolysates are given in Table 3. The chitin-glucan ratio is calculated from the solid-phase carbon 13 nuclear magnetic resonance spectrum. The ratio is variable according to the method of hydrolysis 15 used. The analytical conditions are identical to those used for Fl. Table 3- Molecular characteristics and composition (ash, proteins) of various batches of chitin-glucan hydrolysates (F4) Chitin-glucan NGIc Ash Proteins ratio (titration) (m/m) mol % % % F4 batch 1 26:74 t 3 0.2 ND 0.1 F4 batch 2 25:75 * 2 0 1.2 8.9 F4 batch 3 61:39 t3 0 5.3 3.9 20 * standard deviation over the result of 4 calculations of the chibn-glucan ratio The copolymer according to the present invention clearly has a high degree of purity. 25 19 EXAMPLE 3- Demonstration of the anti-atherosclerosis, antioxidant, blood-cholesterol-lowering and blood-lipid-lowering effect, after oral administration of hydrolysed chitin-glucan 5 The animal model used is the hamster on an atherogenic diet. The hamsters are fed with a diet enriched in cholesterol and deficient in antioxidants (vitamin C, vitamin E and selenium), which brings about a dyslipidemia and arterial lesions similar to the lesions encountered in atheroma plaques in humans (Nistor A, Bulla A, Filip DA & Radu A (1987) 10 The hyperlipidemic hamster as a model of experimental atherosclerosis. Atherosclerosis 68:159). The hamster represents a particularly advantageous animal model of atherosclerosis because of its lipid metabolism, the fact that it is easy to handle and the short period of time required to induce the lesions (from 8 to 12 weeks). It was chosen in 15 order to study the effects of a chitin-glucan hydrolysate since it responds well to procedures aimed at decreasing cholesterol and atheroma (Kowala, MC, Nunnari, JJ, Durham, SK & Nicolosi, RJ (1991) Doxazosin and cholestyramine similarly decrease fatty streak formation in the aortic arch of hyperlipidemic hamsters. Atherosclerosis 91:3549). 20 In this example, two compounds, the characteristics of which are summarized in Table 4, were administered in the daily diet of the hamsters: * 42.85 mg/kg/day of F4 hydrolysed chitin-glucan (i.e. 3 g/day for a man weighing 70 kg) 25 - 42.85 mg/kg/day of F7 chitosan of fungal origin (i.e. 3 g/day for a man weighing 70 kg) 20 The control group receives water by daily gavage in order to obtain the same experimental conditions as the other groups and to prevent any possible differences due to the stress of the gavage. 5 As soon as they are received, 28 Syrian golden hamsters weighing approximately 80 grams are placed in plastic cages, and divided up into three batches of eight animals in a room at 23 0 C, with a hygrometry of 70% and a photoperiod of 12 hours (12N/12D). The food consumption and their weights are measured every day. The groups receive the diet for 10 which the composition is given in detail in Table 5. Table 4- Characteristics of the F4 and F7 compounds F4 F7 Hydrolysed Chitosan chitin-glucan Molecular mass N/A 10000 Chitin (% of the chitin-glucan copolymer) 25 NA Beta-glucan (% of the chitin-glucan copolymer) 75 2 Glucosamine (mol% of the chitin part) 0 90 Ash (%) 1.2 1.3 Proteins (%) 8.9 <1 21 Table 5- Composition of the hamster diet 5 Ingredients (g/KG) Casein 200 DL-methionine 3 Wheat starch 393 Sucrose 154 Cellulose 50 Maize oil 25 Rapeseed oil 25 Mineral mixture 1 35 Vitamin mixture 2 10 Lard 150 Cholesterol 5 ' The mineral mixture contains (mg/kg diet): CaHPO, 17200, KC, 4000; NaCI, 4000; MgO, 420; MgSO, 2000; Fe 2 O, 120; FeSO 4 .7H20, 200; trace elements, 10 400 (MnSO 4 .H0 98; CuSO. 5H20, 20, ZnSO4.7H2, 80; CoSO 4 .7 7 H20, 0.16; K, 0.32; starch, qs 40 g (per kg diet). This mature lacks Na2SeO 3 . 2 Vitamin mixture containing (mg/kg diet). retnol, 12; cholecalciferol, 0.125; thiamine, 40; riboflavin, 30; panthothenic acid, 140; pyridoxine, 20; inositol, 300; cyanocobalamine, 0.1; menadione, 80; nicotinic acid, 200; cholne, 2720; folic 15 acid, 10; p-aminobenzoic acid, 100; biotn, 0.6; starch, qs 20 g (per kg diet). This mixture lacks alpha-tocopherol and ascorbic acid.

22 Tissue sampling. After an experimental period of 12 weeks, the hamsters are placed under fasting conditions for 16 hours and are then anesthetized intraperitonally. Plasma sampling. A blood sample is first taken by intracardiac puncture 5 and then centrifuged at 3500 x g for 10 minutes. The plasma is recovered, aliquoted, and then stored at -80 0 C. The total cholesterol, the HDL-cholesterol level, the LDL-cholesterol level, triglycerides, uric acid and urea will subsequently be determined on these plasmas. Organ sampling. The liver is removed after perfusion with a solution of 10 phosphate buffered saline (1 mM, pH 7.2) containing 1 mM calcium chloride and 0.27% of glucose. The aim of this is to remove the residue blood which could comprise an SOD and GSHPx activity. Said liver is subsequently dried, weighed, and then stored at -80 0 C. The glutathione peroxidase and superoxide dismutase activities will be determined on this 15 organ. The aorta is subsequently removed after fixing the vascular system with a 0.1 M sodium cacodylate buffer, pH 7.4, containing 2.5 mM calcium chloride, 2.5% of paraformaldehyde and 1.5% of glutaraldehyde. The aortic arch is then removed under a binocular lens, opened up 20 longitudinally, pinned out on a piece of cork, and then immersed in the fixing solution and stored at 4 0 C. The atheromateous lesions caused by the diet may be observed after staining the aortic wall lipids. Statistical treatment of the results The values which will be presented in the following section correspond to 25 the mean ± SEM (standard error of the mean) obtained on groups of 8 animals. The significance between the means was established by means of a one-variable ANOVA analysis using a Fischer test by means of the StatView 4.5 software (ABACCUS Concept, Inc). When the values bear an 13 identical superscript letter, this means that these values are not significantly different for P < 0.05. Results 5 a- Determination of the lipid surface area. The surface area of the lipid deposits is determined using an optical microscope equipped with a photographic device, after histological staining according to the method described by Nunnari et al., (Nunnari JJ, Zand T, Joris I & Majno G. (1989) Quantification of oil Red 0 staining of the aorta in hypercholesterolemic 10 rats. Exp. Mol. Pathol. 51:1). Table 6- Percentage of aortic surface area covered with aortic lipid deposits Control F4 F7 Percentage lipid 14.79 ± 4.08a 0.35 i 0.20b 0.57 *0.

3 7 b deposits 15 It is noted that the product according to the present invention is more effective than chitosan. b- Plasma assays Several assays are carried out on the plasmas: 20 0 Biological panel (total cholesterol, triglycerides, HDL, LDL, uric acid, urea), e Assay for antioxidant capacity (TAS).

24 Determination of total plasma cholesterol. The analysis was carried out with kit No. 1489232 Roche/Hitachi, Roche Diagnostics. The assay is based on the technique described by Allain et al., (Allain CC, Poon ILS, Chan CS, Richmond W & Fu PC. (1974) Enzymatic determination of total 5 serum cholesterol, Clin. Chem. 20:470). Determination of plasma triglycerides. The analysis was carried out with kit No. 1488872 Roche/Hitachi, Roche Diagnostics, according to the method developed by Wahlefeld & Bergmeyer (Wahlefeld AW & Bergmeyer HU (1974) in: Methods of enzymatic analysis Second Edition, 10 New York Academic Press p.1831). Determination of plasma HDLs. The analysis was carried out with kit No. 1930672 Roche/Hitachi, Roche Diagnostics. The HDLs are separated according to the techniques described by Marz & Gross (Marz W & Gross W. (1986) Evaluation of a phosphotungstic acid/MgCl 2 precipitation and 15 quantitative lipoprotein electrophoresis assay. Clin. Chim. Acta. 158:33). Determination of plasma LDLs. The plasma LDL-cholesterol content is calculated by the difference between the total cholesterol content and the HDL-cholesterol content. 20 Table 7- Summary of the biochemical parameters Control F4 F7 Total cholesterol (g/l) 3.10 * 0.30a 2.53 * 0.21b 2.37 + 0.03b Triglycerides (g/I) 1.96 i 0.55a 1.04 0.27bd 0.60 0.21bc DL (g/1) 0.57 ± 0.16a 2.01 * 0.11bd 1.84 0.09bc DL (g/1) 2.13 i 0.2a 0.24 t 0.05b 0.26 0.09b It is noted that the products of the present invention have an effect equivalent to chitosan.

25 Determination of urea. The analysis was carried out with kit No. 1489364 Roche/Hitachi, Roche Diagnostics. This urea assay is based on a UV kinetic method described by Talke and Schubert (Talke H & Schubert 5 GE. (1965) Enzymatische Harnstoffbest timmung im blut und serum im optischen test nach Warburg. Klin. Wochenschr. 43:174). Determination of uric acid. The analysis was carried out with the COBAS INTEGRA 400/700/800 Uric Acid ver. 2 (UA2) Roche/Hitachi Kit, 10 Roche Diagnostics. It is an enzymatic colorimetric assay according to the modified method of Town et al., (Town MH et al., (1985) J. Clin. Chem. Clin. Biochem. 23:591). Table 8- Plasma enzymatic activities Control F4 F7 Uric acid (pmol/I) 255.00 ± 37.851 100.75 i 62.02 82.25 * 21.70 Urea (mmol/l) 14.87 ± 5.581 4.00 ± 0.37 5.25 ± 0.25 15 It is noted that the plasma enzymatic activity of the products of the present invention is better than or equivalent to that of chitosan. 20 Assaying of plasma antioxidant capacity (TAS). This parameter is determined using the Randox No. NX2332 Kit (Laboratoire Randox), the method of which is based on the technique of Miller et al., (Miller NJ, Rice Evans C, Davies MJ, Gopinathan V & Milner A. (1993) A novel method for measuring antioxidant capacity and its application to monitoring the 25 antioxidant status in premature neonates, Clinical Science. 84:407).

26 Table 9- Plasma antioxidant activity Control F4 F7 Antioxidant capacity 1.03 t 0.085 1.37 0 07 0.89 t 0.0* (mmol/l) It is noted that the products of the present invention have a plasma 5 antioxidant activity that is entirely surprising and not comparable to that of chitosan, which inhibits the plasma antioxidant activity. c- Assaying liver enzyme activities Preparation of cytosolic fractions of liver. The liver enzyme activity is 10 measured on cytosolic fractions; specifically, since the enzymes are in the cytosol, it is necessary to perform a two-step ultracentrifugation: a first centrifugation of the liver homogenates at 5% in 0.15M NaCl, at 8000 x g for 20 minutes at 4 0 C, which makes it possible to recover a supernatant. The latter then undergoes a centrifugation at 105 000 x g for one hour at 15 4 0 C. The cytosol is stored at -80 0 C for the assays. The protein assay is carried out by the bicinchoninic acid method, according to Smith et al., (Smith PK et al., (1985) Measurement of protein using bicinchoninic acid. Anal. Biochem. 150:76). Glutathione peroxidase activity (Se-GSHPx). The measurement of 20 the activity of this enzyme is based on the ability of the sample to catalyse the oxidation of glutathione by aqueous hydrogen peroxide, according to the method of Wendel (Wendel A. (1981) Glutathione peroxydase. Methods in enzymology, 77:327) 27 Table 10- Specific activity of liver Se-GSHPx Control F4 F7 Se-GSHPx 109.12 t 88.945 134.04 * 1.495 142.85 ± 54.605 (U/mg proteins) It is noted that the products of the present invention have a liver enzyme 5 activity equivalent to that of chitosan. Superoxide dismutase activity (SOD). The activity of SOD is determined with the SOD 525 Kit (Tebu-Bio) according to the method of Paoletti and Mocali (Paoletti F & Mocali A. (1990) Determination of 10 superoxide dismutase activity by purely chemical system based on NADCPJH oxidation, Methods Enzymology. 186:209). Table 11 : Specific activity of liver SOD Control F4 F7 SOD 0.58 t 0.565 0.03 ± 0

.

0 2 bd 0.04 i 0.01c' (U/mg proteins) 15 It is noted that the products of the invention have an activity on superoxide dismutase comparable to that of chitosan. To summarize the results, Tables 12 and 13 bring together the variations 20 in the various parameters expressed as % relative to the control group.

28 Table 12- Variations in the surface area of aortic lipid deposits and in the liver enzyme activities expressed as % relative to the control group Se-GSHPx SOD Percentage lipid (U/mg proteins) (U/mg proteins) deposits F4 +22.8% -94.8% -97.6% F7 +30.9% -93.1% -96.1% 5 Table 13- Variations in the various biochemical parameters expressed as %, relative to the control group. Total Triglycerides HDL LDL Antioxidant Uric acid Urea cholesterol (/) (g/) (g/l) capacity (pmol/l) (mmol/1) (0/) (mmol/l) F4 -18.4% -46.9% +252.6% -88.7% +33.1% -60.5% -73.1% F7 -23.5% -69.4% +222.8% -87.8% -13.6% -67.7% -64.7% Total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol are 10 biochemical parameters which make it possible to note the blood cholesterol-lowering effects of the hydrolysed chitin-glucan and of chitosan. In fact, the decrease in total cholesterol and in LDL-cholesterol (significant decrease by a factor of 10) compared to the control group make it possible to confirm the effectiveness of the hydrolysed chitin 15 glucan and of chitosan in preventing the development of atheroma plaque and, consequently, on cardiovascular diseases. The increase in HDL-cholesterol is spectacular. It reflects the fact that the efflux of cholesterol from the peripheral organs to the liver is promoted, 20 thus decreasing the risk of deposits and of oxidation of particles rich in cholesterol in the organs and the arteries. The treatments based on F4 and F7 make it possible to invert the HDL/LDL levels compared to the control. The percentage of the surface area of the aortic arch covered with lipid 5 deposits and foam cells is a direct indicator of the development of atheromateous lesions. Compared with the controls, the two types of treatment very significantly reduce this percentage, with a level of effectiveness that is virtually similar, around 97%. Now, compounds reputed to be very effective in reducing lipid deposits, such as wine 10 polyphenols, exhibit a reduction in surface area of the aortic arch covered with lipid deposits of 70 to 90% according to the molecules studied with the same hamster molecule on an atherogenic diet (Auger R et al., J. Agric. Food Chem. (2005) 53:9823; Auger R et al., (2005) J. Agric. Food Chem. 53:2015; Auger R et al., (2004) J. Agric. Food Chem. 52:5297). 15 Only F4 increases the plasma antioxidant capacity, by 33.1% compared with the control group. As regards the activities of the liver enzymes involved in the antioxidant system, it is observed that the selenium dependent glutathione peroxidase activity is increased, and that the SOD 20 activity is greatly decreased by the treatments with F4 and F7 compared with the control group. A very large decrease (60 to 70%) in uric acid and also in urea in the plasma can also be noted for two groups treated with F4 and F7. The 25 decreases observed reflect a greater elimination of uric acid and of urea by the kidneys, which decreases the risk of hyperuricemia, a parameter which is known to promote atheroma plaque development.

30 The considerable improvement in the lipid profile and in the associated parameters for the animal model used makes it possible to conclude that the regular consumption of hydrolysed chitin-glucan is of benefit in preventing atherosclerosis and, by extension, obesity, with effects that are 5 comparable to, or even better than, those induced by the consumption of chitosan. Example 4 Effect of the oral administration of chitin-glucan on the gastrointestinal tract, carbohydrate profile and lipid profile in 10 the rat Protocol The model used is the normal rat given a standard diet and drink enriched in fructose (21%), which promotes hepatic steatosis, via rapid 15 metabolisation of the fructose by the liver, resulting in hypertriglyceridemia and hyperinsulinemia and a reduction in the action of insulin in skeletal muscle and the liver. The chitin-glucan (table 14) is administered in the daily diet of the rats at 20 a rate of 10%, which is a dose capable of generating an acute effect in the animal. The short-term and long-term effects are studied. The control group receives a standard diet enriched in fructose (table 15). 10 male Wistar rats weighing approximately 100-125 g are divided up into cages in two groups (control/treated) in a room at 23 0 C, with a hygrometry of 70% 25 and with a photoperiod of 12 hours (12N/12D). Food consumption and weight change are measured once a week. The production of faeces over 24 h and the water content of the latter are estimated after 2 weeks of treatment. After the acclimatization period (1 31 week), during which the animals receive a standard diet not enriched in fructose, an evaluation of gastric emptying and of the glycaemic response in the presence of the chitin-glucan is carried out. The rats are given no food for 18 hours. The treated group receives a solution of glucose 5 paracetamol-chitin-glucan (10%) by gavage, while the control group receives a glucose-paracetamol solution. Blood samples are taken for 2 hours (blood glucose level, blood insulin level, paracetamol). Similarly, an evaluation of gastric emptying and of the glycaemic response in the absence of chitin-glucan is carried out after 3 weeks of treatment. In this 10 case, the rats are given no food for 18 h and a glucose-paracetamol solution is administered by gavage for 2 days. Blood samples are taken for 2 hours (blood glucose level, blood insulin level, paracetamol). Over the course of the third week of treatment, the rats are given no food for 18 hours. Subsequently, an evaluation of the orofecal transit time is carried 15 out. Diets coloured with a solution of carmine red are given to the rats. The time for the first coloured faeces to appear is determined. After 4 weeks of treatment, the rats are anaesthetized and a laparotomy is performed. The blood from the portal vein and the vena cava is 20 centrifuged in order to recover the serum and/or the plasma. The lipid (total cholesterol, HDL-cholesterol, LDL-cholesterol) and carbohydrate (glucose, insulin) profiles are analysed using the latter. The various organs are removed, weighed and conserved in order to estimate the caecal fermentation (caecal proliferation, caecal pH, short-chain carboxylic acid 25 content), the lipid content of the liver and the faeces, and the adipose mass (weight of epidydimal and visceral adipose tissues).

32 Results The results show that a regular consumption of chitin-glucan promotes a balanced intestinal transit and a balanced homeostasis of lipid and carbohydrate profiles in a rat model. It Is seen that the "fibre effect" 5 has a preventive effect on parameters directly related to metabolic diseases such as hypercholesterolaemia, diabetes or, by extension, metabolic syndrome and obesity. In fact, the fibre reduces the caloric density of food (number of calories per 100 g), significantly slowing down gastric emptying and food digestion, and significantly reduce insulin 10 secretion. These effects together result in a spontaneous reduction in calorie consumption and in the feeling of being hungry. The chitin-glucan induces fermentation at the caecal level. This fermentation is accompanied by short-chain fatty acid production which is 15 signficantly higher in the group receiving the chitin-glucan compared with the control group, by influencing epithelial cell homeostasis. This thus contributes to reducing the risks of atrophy, to stimulating the recovery of a damaged intestinal epithelium, and/or to inhibiting cell hyperproliferation. 20 Table 14- Molecular characteristics and composition of the chitin-glucan copolymer Chitin-glucan Ash Proteins Lipids Heavy metals ratio 35/65 2.3 7.71 1.5 < 20 25 Table 15- Rat food composition (standard A04 diet, UAR, France) Proteins 19.3 Carbohydrates : 70.4 - Cellulose 5 - Starch 38 - Sucrose 3 - Other undigestible 8 substances Lipids 3 Mineral/vitamin mixtures 7.3 Table 16- Variation in the biochemical and physiological parameters of the groups of rats having consumed the chitin-glucan, compared with the control group Chitin-glucan (CG) Weight change Food consumption Blood glucose level Blood insulin level Adipose mass Faecal production over 24 h ?1 Gastric emptying Orofaecal transit Caecal fermentation ?' 5 NI significantly lower than the value for the control group (p<0.05); ?1: significantly higher than the value for the control group (p<0.05); significantly unchanged (p<0.05) 10 Example 5 Water absorption capacity of chitin-glucan In order to mimic the behaviour of the chitin-glucan in the gastrointestinal tract, powdered chitin-glucan is brought into contact with water, NaCl and aqueous solutions at various pHs. After a contact time of 12 hours with stirring, the chitin-glucan is separated by centrifugation and the wet mass 15 is determined.

35 Table 17- Swelling capacity of chitin-glucan in various media (g of water absorbed per 100 g of dry chitin-glucan) Water 5% NaCl pH 3 pH 5 pH 7 pH 9 7 7 7 6 7 7 5 Results It is seen from this example that the chitin-glucan is capable of absorbing approximately 6 times its mass of water or of an aqueous medium, which is of the same order of magnitude as the degree of swelling of the known 10 commercial insoluble dietary fibres, for instance hemicellulose and pectin (4 to 8 times their mass of water). Example 6 Demonstration of the anti-atherosclerosis, antioxidant, blood-cholesterol-lowering and blood-lipid-lowering 15 effect after oral administration of chitin-glucan in the hamster Protocol The model used is the same as that presented in example 3. In this example, two compounds, the characteristics of which are summarized in 20 table 18. were administered in the daily diet of hamsters: e CG2 group: 42.85 mg/kg/day of chitin-glucan (i.e. 2 g/day for a man weighing 70 kg) " CG1.5 group : 21.43 mg/kg/day of chitin-glucan (i.e. 1.5 g/day for a man weighing 70 kg) 25 o Cs2 group: 28.57 mg/kg/day of chitosan (i.e. 2 g/day for a man weighing 70 kg) 3b The control group receives water by daily gavage in order to obtain the same experimental conditions. Table 18- Characteristics of the chitin-glucan and chitosan compounds 5 Chitin-glucan Chitosan (CG) (Cs) Molecular mass N/A 29,000 Chitin (% of the chitin-glucan 35 N/A copolymer) Beta-glucan (mol% of the chitin 65 2.1 component) Glucosamine (mol% of the chitin 0 89 component) Ash (%) 2.3 2.66 Protein (%) 7.7 0.31 As soon as they are received, 48 Syrian golden hamsters weighing approximately 100 g are placed under the same experimental conditions of example 3. The food consumption and their weights are measured 10 every day. The groups receive the same food as that presented in example 3 (table 5). Results 37 The samplings, the statistical analyses and the analytical methods are the same as those presented in example 3. All the results are presented in table 19. 5 Table 19- Variation in the biochemical parameters of the groups of hamsters having consumed the chitin-glucan and the chitosan, compared with the control group CG2 group CG1.5 Cs2 group (2 g/day) group (1.5 (2 g/day) g/day) Total cholesterol N N S Triglycerides N N S HDL-cholesterol ?1 71 71 LDL-cholesterol N N N Antioxidant capacity ? Uric acid Urea N Se GSHPx ? SOD Percentage of lipid deposits N : significantly lower than the value for the control group (p<0.05); 71: significantly higher than the value for the control group (p<0.05) 10 It is seen from this example that the chitin-glucan brings about the same variations in the biochemical parameters of the rats on an atherogenic diet as the products studied in example 3. The chitin-glucan considerably improves the lipid profile and the associated parameters, at the two doses 38 studied. Regular consumption of chitin-glucan is therefore beneficial in the prevention of atherosclerosis and, by extension, of related pathologies. It is to be understood that, if any prior art publication is referred to 5 herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country. In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express 10 language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. 15

Claims (19)

1. Use of at least one polysaccharide of fungal origin comprising predominantly a chitin-glucan copolymer, for the manufacture of a 5 composition administered orally to a human being or an animal, for obtaining an effect chosen from the group consisting of an antioxidant, blood cholesterol-lowering or blood-lipid-lowering effect, a stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating 10 and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia.

2. Method for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a 15 stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and 20 hyperuricemia, comprising administering orally to a human being or an animal an effective amount of a composition comprising at least one polysaccharide of fungal origin comprising predominantly a chitin-glucan copolymer.

3. Use according to Claim 1 or method according to Claim 2, wherein the 25 hypoglycaemic effect is obtained in a human or animal having diabetes.

4. Use or method according to any one of Claims 1 to 3, wherein the animal is a non-human mammal. 40

5. Use of at least one polysaccharide of fungal origin that is insoluble in an aqueous or organic medium, said polysaccharide comprising predominantly a chitin-glucan copolymer, for the manufacture of a composition administered orally, as antioxidant, blood-cholesterol-lowering or blood-lipid-lowering 5 composition, for stimulating the immune system, for a hypoglycaemic effect, for a satiety effect, for improving food transit, or for preventing, or treating, or combating a pathology selected from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes, and hyperuricemia. 10

6. Method for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating and/or combating a pathology chosen from the 15 group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia, comprising administering orally an effective amount of a composition comprising at least one polysaccharide of fungal origin that is insoluble in an aqueous or organic medium, said polysaccharide comprising 20 predominantly a chitin-glucan copolymer.

7. Use or method according to any one of Claims 1 to 4, wherein said chitin-glucan copolymer comprises a ratio of chitin to beta-glucans of between 70:30 and 20:80.

8. Use of at least one extract of fungal origin containing essentially a 25 polysaccharide as defined in any one of the preceding claims, for the manufacture of a composition administered orally, as antioxidant, blood-cholesterol-lowering or blood-lipid-lowering composition, for stimulating the immune system, for a hypoglycaemic effect, for a satiety 41 effect, for improving food transit, or for preventing, or treating, or combating a pathology selected from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes, and hyperuricemia. 5

9. Method for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting in preventing and/or treating and/or combating a pathology chosen from the 10 group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia, comprising administering orally an effective amount of a composition comprising at least one extract of fungal origin containing essentially a polysaccharide as defined in any one of the preceding claims. 15

10. Use according to Claim 8 or method according to Claim 9, characterized in that the polysaccharide comprises more than 7 0% of chitin-glucan polysaccharides by mass relative to the total mass of the extract of fungal origin.

11. Use or method according to Claim 10, characterized in that the 20 polysaccharide comprises greater than 85% of chitin-glucan polysaccharides by mass relative to the total mass of the extract of fungal origin.

12. Use or method according to any one of the preceding claims, characterized in that Aspergillus nigeris used as fungal origin.

13. Use or method according to any one of the preceding claims, 25 characterized in that a hydrolysate of the polysaccharide defined in any one of the preceding claims is used. 42

14. Use or method according to Claim 13, characterized in that the chitin glucan hydrolysate has a ratio of chitin to beta-glucans of between 60:40 and 15:85 (m/m).

15. Use or method according to any one of the preceding claims, 5 characterized in that at least 85% of the chitin part of the chitin-glucan copolymer is N-acetyl-D-glucosamine units, and that at most 15% is D glucosamine units.

16. Use or method according to any one of the preceding claims, characterized in that the composition is intended for an effect blood 10 cholesterol-lowering or blood-lipid-lowering effect.

17. An oral pharmaceutical formulation comprising a pharmaceutically effective amount of at least one extract of fungal origin comprising predominantly a chitin-glucan copolymer or hydrolysate thereof and pharmaceutically orally acceptable excipients and optionally other active 15 ingredients, said chitin-glucan copolymer or hydrolysate thereof comprising a mass ratio (m/m) of chitin to beta-glucans of between 50:50 and 10:90, when used for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a stimulatory effect on the Immune system, a hypoglycaemic effect, a satiety 20 effect, an effect which improves food transit, and an effect consisting in preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and hyperuricemia. 25

18. A food composition comprising at least one extract of fungal origin comprising predominantly a chltin-glucan copolymer or hydrolysate thereof, 4731308_1 (GHMaders) P79261 AU 43 said chitin-glucan copolymer or hydrolysate thereof comprising a mass ratio (m/m) of chitin to beta-glucans of between 50:50 and 10:90, when used for obtaining an effect chosen from the group consisting of an antioxidant, blood-cholesterol-lowering or blood-lipid-lowering effect, a 5 stimulatory effect on the immune system, a hypoglycaemic effect, a satiety effect, an effect which improves food transit, and an effect consisting In preventing and/or treating and/or combating a pathology chosen from the group consisting of dyslipidemia, atherosclerosis, obesity, an obesity-related disease, a cardiovascular disease, metabolic syndrome, diabetes and 10 hyperuricemia.

19. Use according to any one of Claims 1, 5 and 8; method according to any one of Claims 2, 6 and 9; an oral pharmaceutical composition according to Claim 17; or a food composition according to Claim 18; substantially as herein described with reference to any one of the Examples. 15 4731306_1 (GHMatteir) P79261.AU