JPS61106516A - Hypoglycemic agent - Google Patents

Abstract

PURPOSE:A hypoglycemic agent containing a polysaccharide which is a water-soluble component of a plant belonging to Dioscorea genus, Dioscoreaeae family, as an active component. CONSTITUTION:The raw or dried rhizome or propagule of a plant belonging to Dioscorea genus, Dioscoreaeae family (e.g. Dioscorea japonica, Dioscorea batatas, Dioscorea bulbifera, Dioscorea gracillima) is crushed or pulverized, and extracted with water or aqueous organic solvent (e.g. methanol). The amount of the extractant is 1.5-4 times volume of the raw material. The extracted liquid is concentrated and dried under reduced pressure, and further purified to obtain the polysaccharide useful as the active component. A hypoglycemic agent having little side effect can be prepared by using said polysaccharide as the active component. Dose: 10-300mg, preferably 30-100mg of the active component daily in 2-3 divided doses, in the form of an oral drug such as tablet, capsule, syrup, etc., or an injection.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the family Dioscoreaceae (D 1oscoreacea).
e) A hypoglycemic agent containing as an active ingredient a polysaccharide that has a hypoglycemic effect and is contained in a plant belonging to the genus Dioscorea.

Herbal medicines from plants belonging to the genus Dioscorea, especially Dioscorea, have been used for a long time as tonics, sedatives, hypothermics, antipyretics, and complementary medicines in Chinese medicine. It is not known to have any effect.

The inventors of this invention discovered that the above-mentioned herbal medicine had a hypoglycemic effect, and as a result of further research, they found that the water-soluble components of the herbal medicine (Yamayaku) from Nagaimo, which belongs to the family Dioscoreaceae and the genus Dioscorea, precipitate in ethanol and reduce blood sugar levels. The present invention was achieved by obtaining a polysaccharide having a depressing effect.

The properties of the obtained polysaccharide vary depending on the type of raw material plant, but all have the following unique properties.

(i) Water soluble (ii) Hypoglycemic (iii) A mixture of 2% phenol aqueous solution and concentrated sulfuric acid exhibits a pale yellow-red color and is positive in silver mirror reaction and Fehling's test solution (
Thus, the present invention provides a hypoglycemic agent containing as an active ingredient a polysaccharide, which is a water-soluble component of a plant belonging to the Dioscoreaceae family and is characterized by having a hypoglycemic effect. It provides:

Examples of plants belonging to the family Dioscoreaceae and the genus Dioscorea that contain the polysaccharide of the present invention include the following.

Dioscorea (Deioscoria japonica sumbe):
Dioscorea japonica Thunb,
), Dioscorea Batatas Decne,
), Nigakashiyu (Deioscoria vulvihuera)
Lin: Dioscorea bulbiferaLi
nn, ), Tachidokoro (Dioscoria gracilima φ)
Miku: Dioscorea gracillia+a
Miq, ), Tsukushitachidoko O (Dioscorea
ascleptadea Prain etBurk
among them, yam and yam are easily available and convenient.

As raw materials for the active ingredient of this invention, raw or dried rhizomes of the above-mentioned plants or rhizomes are used. Of course,
A herbal medicine made from the rhizome of Japanese yam can also be used as a raw material in this invention.

The polysaccharide which is the active ingredient of this invention can be obtained as follows.

First, the rhizomes or stems of the above-mentioned raw material plants are washed with water, crushed or crushed, and then washed with water or an aqueous organic solvent.
1.5 to 4 times the amount of the raw material). Although water is sufficient for extraction, an aqueous organic solvent may be used to prevent spoilage of the extract and to promote extraction. Alternatively, both may be extracted. As the organic solvent of the aqueous organic solvent, a lower alcohol such as methanol or ethanol is used, and depending on the type of raw materials, an organic solvent containing 50% or less, preferably 30% or less is used. This extraction is also facilitated by heating.

The obtained extract is concentrated to dryness under reduced pressure at a temperature below 40°C. If foaming occurs at this time, it can be defoamed by adding 11-i butanol. Profit 1
The resulting powder is poured into 20 to 40 times the amount of water and stirred sufficiently to dissolve. After filtering the obtained solution under reduced pressure using a Nutsche filter, a glass filter, etc. to remove insoluble matter,
The filtrate is added dropwise little by little to 4 to 6 times the amount of lower alcohol such as methanol or ethanol. This ethanol solution is allowed to stand to sufficiently form a precipitate. This precipitate is filtered under reduced pressure using a Nutsche filter, a glass filter, etc., and a lower alcohol mixed with a small amount of water, such as water:ethanol (1:
5) Washing with the mixed solution and then drying in a desiccator yields a powdered polysaccharide which is the active ingredient of the present invention.

It has been found that the polysaccharide obtained as described above has an excellent hypoglycemic effect and almost no side effects, as described below.

The dosage of the hypoglycemic agent of this invention varies depending on the medical condition, but when administered internally to adults, the amount of the above-mentioned active ingredient is 10 to 300 μ per day, preferably 30 to 100 μ per day, divided into 2 to 3 doses. It can be effective by

The hypoglycemic agent according to the present invention consists of the above polysaccharide alone or a mixture thereof, and a solid or liquid excipient. The administration method and dosage form are usually powders, tablets including sublingual tablets, emulsions, capsules, drugs,
There are oral forms such as granules and liquids (including liquid extracts and syrups). It may also be in the form of an injection.
Solid or liquid excipients used here include:
Those known in the art are preferably formulated to contain the compounds of this invention required for a single dose, such as those just described above.

Excipients in powders and other powders for internal use include lactose, starch, dextrin, calcium phosphate, calcium carbonate, synthetic and natural aluminum silicates, magnesium oxide, dry aluminum hydroxide, stearin, to name a few specific examples. Examples include magnesium acid, sodium bicarbonate, and dried yeast.

In addition, transdermal absorption agents prepared by adding ordinary excipients are also included in the present invention.

The polysaccharide of this invention can be used as a health food in an amount that does not exhibit any medicinal therapeutic effect and is sufficient to maintain health. The swelling agents include liquid preparations, capsules, soft capsules,
Granules, tea preparations, etc. are suitable.

Next, the present invention will be explained using manufacturing examples and animal experiments.

Ta JJL! Dry product (410 g) of Japanese wild medicine (450 g) of rhizomes of Lt-wounded Japanese yam (Deioscoria batatus Decune) was ground, and the resulting powder was mixed with 800 mff1 of methanol.
It was extracted by immersing it in a water (1:1) mixture overnight at room temperature.

After performing this extraction twice, do the same for 800mj! Extracted three times with each portion of water. The extracts were combined and filtered through Celite, and the filtrate was concentrated to dryness under reduced pressure at 40°C or below.
g of light brown powder was obtained.

This powder was poured into 1,400 ml of water, sufficiently stirred to dissolve it, and the insoluble matter was removed by suction filtration through a glass filter.
Stirring L q h < ra drops -F, ta. . . After the two solutions were allowed to stand overnight, the resulting precipitate was collected by suction filtration through a glass filter and washed with a small amount of ethanol:water (5:1) mixture. It was then dried in a desiccator overnight to obtain 28.2 g of the polysaccharide of the present invention as a white powder.

The ethanol filtrate was evaporated to dryness to obtain 10.0 g of an ethanol-soluble pale yellow powder.

The physical properties of the white powder polysaccharide are as follows, and it has a hypoglycemic effect as described below: i) Infrared absorption spectrum (KBr method) ymax: 3380 (broad), 1720.
1590.1400.1130.1070 and 625a
m"if) nuclear magnetic resonance spectrum (90MHz,
D20) 5.24 (s), 4.97 (S), 4
．． 87-4.42 (s+), 4.39 (s), 4.
12(s), 3.65(s), 3.49(s),
3.24(s), 2.42(s) and 1.15(t
+j =7.16) iii) Decomposition temperature 165℃ iv) pH 100■ with distilled water IQ+mj! The pH of the solution is 5.45.

■) Specific optical rotation [α] 2♂+1.8° (c=0.5, H2O>vi
) Solubility Soluble in water, benzene, ether, chloroform,
Insoluble in alcohol and acetone.

vi) Coloration reaction A pale yellow-red color is formed with a mixture of 2% phenol aqueous solution and concentrated sulfuric acid,
Positive for silver mirror reaction and Fehling's test solution.

Ta J! ] J8L Zobetsu” - Grind the dried product (124.2 g) of the shell (360 g) of Japanese yam (Deioscoria japonica sumbe), and mix the obtained powder with 500111β methanol:water (1
: 1) Extracted by immersing in the mixture overnight at room temperature. After this extraction was performed twice, the mixture was similarly extracted three times with 500 mji of water each time. The extracts were combined and filtered through Celite, and the filtrate was concentrated to dryness under reduced pressure at 40° C. or lower to obtain 10.3 g of light brown powder. This powder was poured into 3001111 water and sufficiently stirred to dissolve it, suction filtered through a glass filter to remove insoluble materials, and the filtrate was dropped into 1500 mj+ ethanol. After this ethanol solution was left overnight, the formed precipitate was collected by suction filtration through a glass filter, washed with a small amount of ethanol:water (5:1) mixture, and then dried overnight in a desiccator to give a light yellowish brown color to the present invention. 3.7 g of polysaccharide was obtained. The ethanol filtrate was evaporated to dryness to obtain 3.9 g of an ethanol-soluble pale yellowish brown powder.

The obtained polysaccharide has the following physical properties and has a hypoglycemic effect as described below.

i) Solubility Soluble in water, insoluble in benzene, ether, chloroform, alcohol and acetone.

ii) Color reaction A pale yellow-red color is obtained with a mixture of 2% phenol aqueous solution and concentrated sulfuric acid,
Positive for silver mirror reaction and Fehling's test solution.

Groups of 5 mice (Std, ddY, weighing 25-30 g) were created. Blood was collected from the fundus vein of each mouse using a hematocrit tube, and immediately centrifuged at 12,000 rpm for 5 minutes to collect plasma. get. The amount of glucose in the plasma is measured using a glucose analyzer (Yatron M-7000, manufactured by Yatron Co., Ltd.) and taken as the blood sugar level before administration (Ohr). Immediately after Ohr's blood collection, the sample dissolved in physiological saline is administered intraperitoneally.

Blood was collected 7 hours and 24 hours after administration of the sample, and the amount of glucose in the plasma was measured.The relative value when the Qhr blood sugar level was taken as 100 was determined, and the relative blood sugar level was shown in Table 1. Results were expressed as standard error above the mean, and significant differences were determined by one-dimensional analysis of variance.

(Margins below, continued on next page) Table 1 Notes = (1) Samples other than those on the manufacturing side were manufactured using the respective raw materials in a manner similar to Manufacturing Example 1. 1(2
) ****, ** and * are P < 0.001, respectively.
, P < 0.01 and P < 0.05 significance levels.

From the above results, it is clear that polysaccharides from plants of the genus Dioscorea have an excellent hypoglycemic effect.

Claims (1)

[Scope of Claims] 1. A hypoglycemic agent characterized by containing as an active ingredient a polysaccharide which is a water-soluble component of a plant belonging to the genus Dioscorea of the family Dioscoreaceae and is characterized by having a hypoglycemic effect. 2. Plants belonging to the genus Dioscorea of the Dioscoreaceae family are Dioscorea (Deioscoria japonica sumbe), Nagaimo (Deioscoria batatus, Decune), Nigakashiyu (Deioscoria vulvihuera Linn), Tachidokoro (Deioscoria gracilima miku), and Tsukushitachidokoro (Deioscoria gracilima miku).・The hypoglycemic agent according to claim 1, which is Asclepiadeia plain e Berkill).