JPH07238031A - Antihyperglycemic agent - Google Patents

Abstract

PURPOSE:To provide an antihyperglycemic agent exhibiting an excellent antihyperglycemic activity. CONSTITUTION:An antihyperglycemic agent contains as an active ingredient an acidic heterogeneous polysaccharide which is separated from the fruit body or mycelium of KINJI (a mushroom belonging to the Tremellaceae in the Tremellales, and including Tremella aurantia, Tremella mesenterica, and Tremella encephola), and which is insoluble in organic solvents and soluble in water. The acidic heterogeneous polysaccharide is obtained by extracting the fruit body or mycelium of the KINJI, its crushed product or ground product, or its dried product or dried and crushed product with an organic solvent, preferably ethyl alcohol, extracting the extraction residue with water or an aqueous solution containing a polar organic solvent in an amount of <=20wt.%, concentrating the extraction solution under reduced pressure, subjecting the concentrated solution to a precipitation treatment with a polar organic solvent (preferably ethyl alcohol), and subsequently filtering or centrifugally separating the obtained precipitates. Prior to the precipitation treatment, a dialysis treatment is preferably performed. The extraction solution before the precipitation treatment, its concentrated solution or dried product can also be used as the active ingredient of the antihyperglycemic agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood glucose elevation inhibitor, and more particularly to a blood glucose elevation inhibitor having an acidic heteropolysaccharide as an active ingredient, which is separated from the fruit body or mycelium of the golden ear.

[0002]

2. Description of the Related Art Conventionally, it has been reported that polysaccharides isolated from mushroom fruit bodies or mycelium have a hypoglycemic effect. For example, it has been reported that a protein polysaccharide isolated from a fruiting body or a mycelium of Agaricales has a hypoglycemic effect (JP-A-60-4553).
2) In addition, it has been reported that a polysaccharide isolated from the fruiting body of Ganoderma lucidum belonging to the family Asteraceae also has a hypoglycemic effect (JP-A-60-184025).

[0003]

However, there is no specific report on the blood sugar elevation-inhibiting action of polysaccharides or protein polysaccharides isolated from the fruiting bodies of mushrooms or mycelia, among which the fruiting bodies of golden ears or There is no report on the inhibitory effect of polysaccharides isolated from mycelium on blood sugar elevation.

[0004]

However, the present inventors have
In view of the above circumstances, among the mushrooms, the polysaccharide isolated from the fruiting body or mycelium of the golden ear has been studied for its inhibitory effect on blood sugar increase. As a result, it is isolated from the fruiting body or mycelium of the golden ear. It was found that an acidic heteropolysaccharide which is insoluble in an organic solvent and soluble in water exhibits an excellent effect of suppressing blood glucose increase.

That is, the present invention relates to a blood glucose elevation inhibitor which is separated from the fruit body or mycelium of the golden ear and contains as an active ingredient an acidic heteropolysaccharide which is insoluble in an organic solvent and soluble in water.

In the present invention, the gold ears used as a raw material are the genus Tremellales and the family
Tremellaceae) is a mushroom belonging to another name, which is also known as the golden and silver ears, the golden ears, the yellow ears, and the golden and silver ears. As a gold ear, Tremella aura
ntia), Tremella mesenterica (Tremellamesenter)
ica), Tremella enceph
ola) etc. are known, and they are produced all over the Yunnan province of China.

The acidic heteropolysaccharide, which is the active ingredient of the blood sugar elevation inhibitor of the present invention, is obtained from the fruit body or mycelium of the above-mentioned golden ear through the following first step, second step and third step.

[0008] In the first step, the fruiting body or mycelium of golden ear, its crushed or ground product, its dried product or its dried crushed product is subjected to an extraction treatment with an organic solvent to obtain an extraction residue. As the organic solvent in this case, any organic solvent such as methyl alcohol, ethyl alcohol, acetone, dimethylsulfoxide, diethyl ether, hexane, etc. can be used, and the polarity in which water is dissolved in the range of 30% by weight or less can be used. It is possible to use a solvent solution, but it is preferable to use ethyl alcohol. For example, 10 to 20 times the amount of ethyl alcohol is added to the dried product of the fruit body of the golden ear, and at room temperature or under heating, preferably with stirring,
Extraction treatment is performed for about 10 to 50 hours, and filtration or centrifugation is performed to obtain an extraction residue. It is also possible to add ethyl alcohol to the extraction residue and repeat the extraction process in the same manner.

In the second step, the extraction residue obtained in the first step is subjected to an extraction treatment with water or an aqueous solution in which a polar organic solvent is dissolved within a range of 20% by weight or less to obtain an extract. In this case, methyl alcohol, ethyl alcohol, acetone or the like can be used as the polar organic solvent. In the second step, the extraction residue obtained in the first step is subjected to extraction treatment with water or the above-mentioned aqueous solution, but it is preferable to perform extraction treatment with hot water. For example, 10 to 20 times the amount of hot water is added to the extraction residue obtained in the first step, and the mixture is heated to 3 times with stirring.
Extraction is performed for about 15 hours, and then filtered or centrifuged to obtain an extract. Hot water may be further added to the extraction residue to similarly obtain an extract.

Since the target acidic heteropolysaccharide is contained in the extract obtained in the second step, the extract, its concentrate or its dried product may also be used as an active ingredient of the blood sugar elevation inhibitor. it can.

In the third step, the extract obtained in the second step is
Usually, after concentrating under reduced pressure, precipitation treatment with a polar organic solvent is performed to obtain acidic heteropolysaccharide as a precipitate. As the polar organic solvent in this case, methyl alcohol, ethyl alcohol, acetone or the like can be used, but it is preferable to use ethyl alcohol. For example, after concentrating the extract obtained in the second step to about 1/3 to 1/5 amount, 1 to 5 times amount of ethyl alcohol is added to the concentrate,
The target acidic heteropolysaccharide is precipitated by allowing it to stand at room temperature and then filtered or centrifuged to obtain the acidic heteropolysaccharide as a precipitate.

In the third step, the extract obtained in the second step or its concentrated solution can be directly subjected to the above-mentioned precipitation treatment, but the extract obtained in the second step is usually concentrated under reduced pressure. After that, it is preferable that the concentrated solution is subjected to dialysis treatment, the residual solution is usually concentrated again under reduced pressure, and the concentrated solution is subjected to the above-mentioned precipitation treatment.

The acidic heteropolysaccharide obtained in the third step has the following 1)
~ 7) has the following characteristics. 1) Shows one peak in gel filtration using Toyopearl HW-65 (trade name, manufactured by Tosoh Corporation) 2) Dextran-converted number average molecular weight by gel filtration method is 700,000 to 1.3 million 3) D line of sodium The specific rotation at 20 ° C. is −7 ° 4) From elemental analysis, C = 42.01%, H = 6.08
%, N = 0%, O = 51.89%, Ash = 0.02%
5) Gas chromatography analysis showed that mannose / xylose / glucuronic acid = 4/2/1 (molar ratio) was the main constituent sugar, and in addition, trace amounts of glucose, arabinose and O-acetyl were also included. 6) ¹³ C-NMR analysis reveals that α-D-mannose and β-
D-xylose, β-D-glucuronic acid and a trace amount of O-
Acetyl group exists 7) From the Relaxation Smith decomposition method and the methylation analysis method, 1 → 3
The mannose chain of the bond is the main chain, and the xylose chain of the 1 → 3 bond is the side chain. From the above characteristics, the acidic heteropolysaccharide obtained in the third step is α
The main chain is a D-mannose chain of (1 → 3) bond,
It has a β (1 → 3) -bonded D-xylose chain bonded to the 2-position of the D-mannose residue as a side chain,
Further, it is considered to have a β-D-glucuronic acid residue, a β-D-xylose residue, a trace amount of glucose residue and an arabinose residue.

Thus, the acidic heteropolysaccharide having the above-mentioned characteristics, which is separated from the fruiting body or mycelium of the golden ear, exhibits an excellent effect of suppressing an increase in blood sugar, as described later in detail in Examples.

[0015]

【Example】

Test Category 1 (Separation of acidic heteropolysaccharide) 51.7 g of dried fruit body of Tremella aurantia from Kunming, Yunnan Province, China was crushed, 800 ml of ethyl alcohol was added thereto, and the mixture was stirred at room temperature. While 30
After time extraction treatment, centrifugation was performed to obtain a first extraction residue. To the first extraction residue, 500 ml of 70% ethyl alcohol aqueous solution was added, and the mixture was subjected to extraction treatment for 10 hours while stirring with heating in a boiling water bath, followed by centrifugation to obtain a second extraction residue. It was The same extraction treatment was repeated three more times to obtain a fifth extraction residue.

700 ml of hot water was added to the residue of the fifth extraction, the mixture was subjected to extraction treatment for 8 hours while stirring under heating under reflux, and then centrifuged to obtain a first extraction liquid. The same extraction treatment was repeated 5 times on the extraction residue to obtain the second to sixth extraction liquids.

The first to sixth extraction liquids were combined and the temperature was 40 ° C.
Then, it was concentrated under reduced pressure to 1/5 volume. The concentrated solution was placed in a dialysis membrane (trade name: cellulose tube, size C-65, manufactured by Visques) and dialyzed in running water for 15 hours. The residual liquid (the liquid inside the dialysis membrane) was concentrated under reduced pressure at 40 ° C. to 1/3 volume, to which was added 2 volumes of ethyl alcohol, and the mixture was stirred and allowed to stand at room temperature. The resulting precipitate was centrifuged and dried under reduced pressure at 40 ° C to obtain 21.7 g of the desired acidic heteropolysaccharide. This acidic heteropolysaccharide (hereinafter, TA
(Referred to as P) was subjected to a test for a blood glucose elevation inhibitory effect.

Separately, in the same manner as described above, 51.7 g of a dried product of fruiting bodies of golden ears was obtained to obtain a fifth extraction residue, which was subjected to extraction treatment with hot water to extract the first to sixth extractions. After obtaining the liquid, these were combined and dried under reduced pressure at 40 ° C. to obtain 27.6 g of a dried product of the extract containing the acidic heteropolysaccharide. This dried product (hereinafter, referred to as TA) was subjected to a test for a blood sugar elevation suppressing effect.

Test Category 2 (Test for inhibition of blood glucose increase) In each test group, the blood glucose level immediately before the test was 180 to 200 mg
10 normal mice of dl / dl (ddY strain mice) were used in the test. In the TAP or TA administration group, TAP or TA
To a concentration of 0.5 g / liter and glucose to a concentration of 0.5% by weight, which were dissolved in water and allowed to freely ingest each mouse. A negative control group was allowed to freely ingest a 0.5% by weight aqueous solution, and the temperature was 21 ± 1 ° C. and the humidity was 60%.
Grew up in. Immediately before the start of the test and after the start of the test 1, 4, 7,
On the 10th, 15th and 20th days, the blood glucose level of each mouse was measured by the following method.

Measurement of blood glucose level: Blood was collected from the orbital venous plexus of each mouse using a heparinized hematocrit tube,
Immediately, centrifugation (12000 rpm, 5 minutes) was performed to collect serum. Glucose concentration in serum was measured using Glucose B Test Wako (trade name, manufactured by Wako Pure Chemical Industries, Ltd.)
The blood glucose level was measured by the AA method.

The results are shown in Tables 1 and 2, and the relative blood glucose level in each table is the percentage of the blood glucose level on each day after the start of the test with respect to the blood glucose level immediately before the start (0th day) in percentage. It represents.

[0022]

[Table 1]

[0023]

[Table 2]

[0024]

As is apparent from the above, the present invention described above has an effect of exhibiting an excellent blood glucose elevation suppressing action.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Fumihiro Kojima 495 Kuroiso, Kuroiso City, Tochigi Prefecture No. 10 Shibui House No. 10 (72) Inventor Hideki Sakamoto 47 No. 12 Iguchi, Nishinasuno-cho, Nasu-gun, Tochigi Prefecture (72) Ishiguro Yukio 5-96, Higashimishima, Nishinasuno-cho, Nasu-gun, Tochigi Prefecture

Claims (6)

[Claims] 1. A blood glucose elevation inhibitor, which comprises an acidic heteropolysaccharide that is insoluble in an organic solvent and is soluble in water, which is separated from the fruit body or mycelium of the golden ear, as an active ingredient. 2. A blood glucose elevation inhibitor comprising an acidic heteropolysaccharide as an active ingredient, which is obtained through the following first step, second step and third step. First step: a step of extracting fruit body or mycelium of golden ear, crushed or ground material thereof, dried product thereof or dried crushed product thereof with an organic solvent to obtain an extraction residue. Second step: extraction residue is water. Alternatively, a step of performing extraction treatment with an aqueous solution in which a polar organic solvent is dissolved within a range of 20% by weight or less to obtain the extract solution Third step: Precipitation treatment of the extract solution with a polar organic solvent, and the acidic heteropolysaccharide as the precipitate To get 3. The third step, wherein the extract is dialyzed and the residual liquid is precipitated with a polar organic solvent.
The blood sugar elevation suppressant described. 4. The blood glucose elevation inhibitor according to claim 2 or 3, which is subjected to a precipitation treatment with ethyl alcohol in the third step. 5. An antihyperglycemic agent comprising an extract containing acidic heteropolysaccharide, a concentrate thereof or a dried product thereof as an active ingredient, which is obtained through the following first step and second step. First step: a step of extracting fruit body or mycelium of golden ear, crushed or ground material thereof, dried product thereof or dried crushed product thereof with an organic solvent to obtain an extraction residue. Second step: extraction residue is water. Or a step of obtaining an extract by extracting with an aqueous solution in which a polar organic solvent is dissolved within a range of 20% by weight or less 6. The blood glucose elevation inhibitor according to claim 2, 3, 4 or 5, which is extracted with hot water in the second step.