JPH08291076A - Anorectic agent - Google Patents

Abstract

PURPOSE: To obtain an anorectic agent high in safety, inexpensive, having anorectic effect and also a sustainability of its effect, and useful for preventing obesity by using a chitosan oligo-sugar as an active ingredient. CONSTITUTION: This anoretic agent contains at least one kind selected from a chitosan oligo-sugar and their salts, preferably at least one kind selected from chitobiose, chitotriose and their salts as an active ingredient. Further, the oligo-sugars are expressed by the formula [X is one or more kinds selected from inorganic and organic anions; (n) is 0-4], and e.g. they are preferably obtained by deacetylating a chitin obtained from the shells of Crustacea such as crabs, shrimps, etc., and partially hydrolyzing the obtained chitosan.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an antifeedant containing chitosan oligosaccharide and a salt thereof as an active ingredient.

[0002]

2. Description of the Related Art It is known that the center of animal feeding behavior is in the hypothalamus of the diencephalon. The satiety center and the feeding center are involved in so-called satiety and hunger. That is, when an animal eats food, changes in the levels of satiety and fasting substances in blood occur, and the ventromedial hypothalamic glucose-responsive neurons, which are the satiety centers, or the lateral hypothalamic glucose-sensitive neurons, which are the feeding centers. Stimulate, and each activity is promoted and suppressed, and you feel full.

[0003] Therefore, by administering a substance that changes the activity of these sensitive neurons, it is possible to give a feeling of hunger or a feeling of satiety to induce or suppress feeding behavior, so-called feeding control.

Based on this idea, various glucose analogs have been evaluated conventionally. For example, 5-
Thio-D-glucose, 3-O-methyl-D-glucose [American Physiological Society (Endocrinal Meta
b.1) 238 (1980)], 2-deoxy-D-glucose [Br
ain Research; 202 (1980) 474-478], 2-deoxy-glucose derivative [JP-A-62-20], 2-amino-D-glucose (D-glucosamine) [Aquatic product health function effective utilization development research] 20-25 (1991) Sakata et al.], 1-deoxy-D-glucose [1st Obesity Study Group records 18-20 (1980) Sakata et al.] Are considered to have an effect of inducing food intake. There is.

On the other hand, glucosamine derivatives such as 1-deoxyglucosamine and 1-deoxy-N-acetylglucosamine [JP-A-60-81127] are known as antifeedants.

[0006] In recent years, it is said to be an era of satiety, but obesity is said to be a cause of many diseases such as adult diseases, and an antifeedant substance is attracting attention in order to prevent obesity.

[0007]

However, many of these antifeedant substances do not exist in nature, or even if they are present in very small amounts, they are biochemically or organically chemical for industrial use. In addition, there was a problem in safety and cost when used as a drug or food material. Further, since each of them is a low molecular weight compound, there is a problem that the food intake inhibitory effect is fast but not long lasting.

The present invention has been made in view of the above-mentioned problems of the prior art, and its purpose is high safety, low cost,
It is intended to provide an antifeedant having an antifeedant effect and having a long-lasting effect.

[0009]

Means for Solving the Problems The present inventor has conducted extensive studies in order to achieve the above object, and as a result, when chitosan oligosaccharides and salts thereof were administered to rats, transient weak feeding was observed at an early stage. The present invention was completed by discovering that it has a strong and persistent antifeedant effect despite food induction.

That is, the antifeedant of the present invention is characterized by containing at least one selected from chitosan oligosaccharides and salts thereof as an active ingredient.

The present invention will be described in detail below with reference to preferred embodiments. In the present invention, chitosan oligosaccharide is a compound represented by the following chemical formula 1.

[0012]

Embedded image

X in the chemical formula 1 is an inorganic or organic anion, and specific examples thereof include Cl ⁻ and SO.
₄ ²⁻ , CH ₃ COO ⁻ , CH ₃ CH (OH) COO ^{− and the} like.

Chitosan oligosaccharides are chitosan obtained by deacetylating chitin obtained from crustaceans such as crabs and shrimps, or cell wall components of zygomycetes such as Mucor rouxii which is a kind of mold. Can be obtained by partially hydrolyzing chitosan.

Chitin is present in crustaceans such as crabs and shrimps, as well as in the shells of beetles such as crickets and beetles, and as constituents of cell walls of bacterial cells. It is an abundant biomass resource estimated to be 100 million tons. Chitin can be obtained from these by decalcification and deproteinization.

The deacetylation of chitin is carried out by heat treatment with concentrated alkali.

Further, the partial hydrolysis of chitosan is carried out by heating chitosan with an acid such as hydrochloric acid, acetic acid, formic acid or the like, and then removing the acid, or neutralizing and desalting chitosan, crystallizing and further drying. It can be carried out by a method of pulverizing or dissolving chitosan in a dilute acid and then allowing a chitosan degrading enzyme such as chitosanase or D-glucosaminidase to act. The chitosan oligosaccharide obtained by these methods is usually a mixture of disaccharides to hexasaccharides. In the present invention, it is possible to use in the state of a mixture, but fractionated to each of the desired degree of polymerization,
For purification, methods such as column chromatography and solvent fractionation method can be adopted.

In the present invention, as salts of chitosan oligosaccharides, inorganic acid salts such as hydrochlorides and sulfates of chitosan oligosaccharides and organic acid salts such as acetates, lactates and formates of chitosan oligosaccharides are preferably used.

The antifeedant of the present invention may contain at least one selected from chitosan oligosaccharides and salts thereof as an active ingredient, and can be directly ingested or administered as chitosan oligosaccharides and salts thereof. Also, it can be used by being added or blended with foods, pharmaceuticals, feeds, feeds and the like. For example, when it is used as a medicine, various administration methods such as oral administration, intravenous injection and intramuscular injection can be adopted. In addition, since chitosan oligosaccharide and its salt are easily dissolved in water, addition and blending are easy.

The dose of chitosan oligosaccharide for animals (humans, pets, livestock, fish farming, etc.) depends on the type of animal,
It varies depending on the administration period, the food, drug, feed, feed, etc. to be mixed, but as chitosan oligosaccharide, 0.1 to 1000 mg orally per kg of body weight, 0.01 to 100 m if intravenously injected.
g, 0.01 to 100 mg for intramuscular injection is preferable. Also food,
The amount to be added to the feed or feed is preferably about 0.01 to 10% by weight.

Although the safety of chitosan oligosaccharide has been confirmed, the acute toxicity test result of oral administration in rats was LD ₅₀ > 5 g / kg, just in case.

[0022]

When the antifeedant agent of the present invention is administered to rats, as shown in the Examples below, it induces transient and weak feeding at an early stage, but thereafter exhibits strong and long-lasting effects. It shows an antifeedant effect.

Although the reason for this is not clear, when chitosan oligosaccharides and salts thereof are ingested by an animal, they first stimulate the lateral hypothalamic glucose-sensitive neurons, which are the feeding centers, to transiently weakly ingest them. After exhibiting a food-inducing effect, it is thought that glucose is stimulated in the ventromedial hypothalamus, which is the center of satiety, to give a feeling of satiety, and thus suppresses food intake. In addition, since chitosan oligosaccharides and salts thereof are relatively slow in digestion and absorption as compared with monosaccharides such as glucosamine derivatives, it is considered that the effect of suppressing feeding is sustained. It is considered that this action appears not only in rats but also in other animals including humans.

Further, since the antifeedant of the present invention contains chitosan oligosaccharide and its salt as an active ingredient, which is derived from naturally occurring abundant polysaccharide, it has a high safety and a relatively simple process. Since it can be manufactured by, it is advantageous in terms of cost.

Furthermore, since chitosan oligosaccharides and salts thereof are easily dissolved in water, they can be easily added to and blended with foods, pharmaceuticals, feeds, feeds, etc. , Various injection methods such as intravenous injection and intramuscular injection can be adopted.

[0026]

【Example】

Example 1 (Production of Chitosan Oligosaccharide Hydrochloride Mixture) 100 g of chitosan originating from crab shell and 400 N of 12N hydrochloric acid
ml, and after stirring for 2 hours in a 70 ° C water bath, 400 ml of water
Was added to terminate the reaction, and insoluble matter was removed by filtration with a filter.

Next, 10 g of activated carbon was added, the mixture was stirred for 1 hour for decolorization, and then filtered through a filter to remove the activated carbon.
700 ml of the separated decolorizing solution was obtained.

The separated decolorizing solution was concentrated under reduced pressure while distilling off with hydrochloric acid, and the resulting syrupy concentrate was added with methanol.
300 ml was added, and further 900 ml of acetone was added to precipitate a crystalline precipitate. The precipitate was collected by filtration through a filter and dried under vacuum to obtain 120 g of a chitosan oligosaccharide hydrochloride mixture.

Example 2 (Production of chitosan oligosaccharide acetate mixture) To 250 g of chitosan originating from crab shell, 5 L (liter) of water and 90 g of glacial acetic acid were added and dissolved overnight with stirring.
A viscous solution was obtained.

To this chitosan solution, 50 mg of Bacillus pumilus-derived chitosanase (manufactured by Meiji Seika Co., Ltd.) was added, and the mixture was stirred in a hot water bath at 40 ° C. for 18 hours. After completion of the reaction, the enzyme was inactivated by heating at 80 ° C. for 10 minutes to obtain a chitosan oligosaccharide solution.

Next, the chitosan oligosaccharide solution was spray-dried using a disk type spray dryer (PM type manufactured by Ashizawa Niro Atomizer Co., Ltd.) to obtain 210 g of a chitosan oligosaccharide acetate mixture.

Example 3 (Production of Chitosan Oligosaccharide Hydrochloride of 2 to 6 Sugars) 100 g of the chitosan oligosaccharide hydrochloride mixture (containing monosaccharide to 6 sugars) obtained in Example 1 was added to 300 ml of water. Dissolved.

Then, this solution is treated with an ion exchange resin "DO".
WEX 50W "(trade name, manufactured by Muromachi Chemical Industry Co., Ltd.) was loaded on a glass column (φ8 cm × 100 cm),
A linear concentration gradient of 0 to 5 N hydrochloric acid was used to elute and separate chitosan oligosaccharides having various degrees of polymerization. Each of the chitosan oligosaccharides was converted into a crystalline precipitate by the methanol-acetone precipitation method in the same manner as in Example 1, dried in vacuum, and the dito-6-sugar chitosan oligosaccharide hydrochloride, chitobiose hydrochloride,
Chitotriose hydrochloride, chitotetraose hydrochloride, chitopentaose hydrochloride, and chitohexaose hydrochloride were obtained.

Table 1 shows the yield of each chitosan oligosaccharide hydrochloride and the purity analyzed by liquid chromatography.

[0035]

[Table 1]

Test Example 1 (feeding behavior 1 hour after administration) Wistar King A male adult rats were subjected to a light-dark cycle of 12 hours (light period from 8 am to 8 pm), constant temperature of 21 ± 1 ° C., 45 ± 5.
It was bred under a constant humidity and soundproof environment.

As an experimental group, a solution prepared by dissolving 12 μmol of chitobiose hydrochloride and 8 μmol of chitotriose hydrochloride obtained in Example 3 in a phosphate buffer was injected into the rats through the third intracerebral chronic indwelling catheter. .
In addition, as a comparison group, the monosaccharide glucosamine hydrochloride 24 μmol
Was injected with a solution dissolved in a phosphate buffer solution, and only a phosphate buffer solution was injected into the control group. The injection was performed at 11 o'clock in the light period when the feeding behavior of the rat was not observed, and the feeding behavior of the rat was observed for 1 hour thereafter. The results are shown in Table 2.

[0038]

[Table 2] In Table 2, ND means that it could not be measured because there was no eating behavior.

From the results shown in Table 2, it can be seen that a feeding-inducing effect is observed in each of the experimental groups and the comparative group as compared with the control group administered with the phosphate buffer. However, it can be seen that this effect is more remarkable in the monosaccharide glucosamine hydrochloride used as the comparison group than in the experimental group chitosan oligosaccharide hydrochloride.

Test Example 2 (feeding behavior for 1 hour and 30 minutes after administration) The same rats as used in Test Example 1 were bred under the same conditions as in Test Example 1. From 1 week before the experiment, every morning
At 10 o'clock, 1 ml of distilled water was administered from the gastric tube to allow adaptation to this experiment.

To this rat, as an experimental group, 1200 μmol of chitobiose hydrochloride and 1200 μmol of chitotriose hydrochloride obtained in Example 3, and as a comparative group, 1200 μmol of glucosamine hydrochloride were each dissolved in 1 ml of distilled water and administered. . 1 ml of distilled water was administered to the control group. The administration was performed at 10 o'clock in the light period, and thereafter, the feeding behavior of the rats was observed for 1 hour and 30 minutes. Table 3 shows the results.

[0042]

[Table 3] In Table 3, ND represents that it could not be measured because there was no eating behavior.

From the results shown in Table 3, it can be seen that a feeding-inducing effect is observed in each of the experimental groups and the comparative group as compared with the control group in which only distilled water was administered. However, the experimental group chitosan oligosaccharide hydrochloride had a lower feeding-inducing effect than the comparative group monosaccharide glucosamine hydrochloride, and in particular, with chitotriose hydrochloride, the effect was observed only in 1 out of 6 animals. You can see that did not appear.

Test Example 3 (Change in food intake after administration) The same rats as used in Test Example 1 were bred under the same conditions as in Test Example 1. As an experimental group, a solution prepared by dissolving 12 μmol of chitobiose hydrochloride and 8 μmol of chitotriose hydrochloride obtained in Example 3 in a phosphate buffer was injected into the rats through the third indwelling chronic ventricular catheter. In addition, the control group was injected with only the phosphate buffer. The injection was performed at 19:00 immediately before the dark period, and thereafter, the change in the food intake of the rat was observed every 24 hours. Table 4 shows the results.

[0045]

[Table 4]

From the results shown in Table 4, it can be seen that the feeding suppression effect of each experimental group is more remarkable than that of the control group. Considering together with the results of Test Examples 1 and 2, when chitosan oligosaccharide hydrochloride was administered, there was a transient weak induction of feeding at a very early stage, and thereafter, there was a delay and a strong persistence. It can be seen that it has an antifeeding effect. That is, it can be said that chitosan oligosaccharide hydrochloride is effective as a highly durable antifeedant.

Example 4 (Production of nutritional drink containing chitosan oligosaccharide hydrochloride mixture) Using the chitosan oligosaccharide hydrochloride mixture obtained in Example 1, each component was dissolved in water according to the formulation shown in Table 5. Finally, water was added to 100 ml to prepare a chitosan oligosaccharide hydrochloride mixture-containing nutritional drink. The chitosan oligosaccharide hydrochloride mixture was easily dissolved in water.

[0048]

[Table 5]

Example 5 (Production of Granules Containing Chitosan Oligosaccharide Hydrochloride Mixture) Using the chitosan oligosaccharide hydrochloride mixture obtained in Example 1, the components were powder blended in the formulation shown in Table 6. 2.8kg of granules containing chitosan oligosaccharide hydrochloride mixture were obtained by fluidized granulation using 0.5 wt% guar gum solution as a binder.
Was prepared.

[0050]

[Table 6]

Example 6 (Production of Soft Capsule Containing Chitosan Oligosaccharide Acetate Mixture) Using the chitosan oligosaccharide acetate mixture obtained in Example 2, the components were mixed according to the formulation shown in Table 7 to prepare a stock solution. Then, 300 mg each of this stock solution was filled in a gelatin soft capsule to produce about 3000 soft capsules containing a chitosan oligosaccharide acetate mixture.

[0052]

[Table 7]

Example 7 (Production of Tablet Containing Chitosan Oligosaccharide Acetate Mixture) With the formulation shown in Table 8, each component was powder blended and fluidized granulated using a 0.5 wt% guar gum solution. 2% by weight of sucrose fatty acid ester was added to the granulated product, and 250 mg /
Tablets were made into individual tablets to produce about 10,000 tablets containing the chitosan oligosaccharide acetate mixture.

[0054]

[Table 8]

[0055]

As described above, according to the present invention,
Since the active ingredient is at least one selected from chitosan oligosaccharides and salts thereof that are decomposition products of natural polysaccharides,
It is possible to provide an antifeedant which is highly safe, inexpensive, and excellent in sustaining effects. In addition, this antifeedant,
As it dissolves easily in water, it is easy to handle,
It is easy to add and mix with medicines, feeds, feeds, etc. Therefore, it can be expected to be used as an antifeedant for the prevention of obesity, which is said to cause various diseases.

Claims (2)

[Claims] 1. An antifeedant comprising at least one selected from chitosan oligosaccharides and salts thereof as an active ingredient. 2. The antifeedant according to claim 1, which comprises at least one selected from chitobiose, chitotriose, and salts thereof as an active ingredient.