JP3043888B2 - Colorectal cancer prophylactic agent containing glucomannan partial hydrolyzate as active ingredient - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an acetylene compound having an average molecular weight of 2,000.
0 to partial hydrolyzate of glucomannan derived Kon'n'nyaku 5,000 (hereinafter sometimes referred to as a hydrolyzate) on prevention agent for colon cancer shall be the active ingredient.

[0002] In the present specification, percentages are values by weight unless otherwise specified.

[0003]

2. Description of the Related Art Konjac flour is indigestible (edited by Tokuro Soda and edited by Fujio Egami, "Polysaccharide Chemistry", p. 280, Kyoritsu Shuppan, 1955), and contains about 80% of glucomannan, a water-soluble polysaccharide. It is used as a water-soluble dietary fiber, or as a natural low-energy food and pharmaceutical raw material because of its content. Konjac flour has a beneficial effect as dietary fiber when consumed by humans,
(1) The viscosity of the aqueous solution increases in the processing step;
The konjac flour is disadvantageous in that (2) its use and form of use are limited due to an unpleasant flavor accompanied by an off-flavor, and (3) it has the property of adsorbing minerals necessary for human nutrition. However, when ingesting a food to which the konjac flour is added at the same time as other foods, it absorbs calcium in the food, thereby inhibiting the absorption of calcium, negatively affecting the calcium balance of the living body, and reducing bone tissue ash content. It causes a decrease and causes problems such as osteomalacia [Journal of Nutrition, vol. 112, p. 410, 1982].

When konjac glucomannan is ingested by humans, it is not digested by human digestive enzymes, and adsorbs and excretes cholesterol derived from the diet or bile acids and bile acids in bile, resulting in blood cholesterol. [Journal of Nutrition (Jour
nal of Nutrition), Vol. 97, No. 3
82, 1968], but the polymer structure of dietary fiber is an essential condition for this cholesterol-lowering effect (Satoshi Innan and Shuhei Kiriyama, "Dietary Fiber", p. 145, 1st publishing, 1982). Therefore, the blood cholesterol lowering effect of glucomannan hydrolyzed with cellulase or acid disappears [Journa of Nutrition (Journa).
l of Nutrition), Vol. 102, 168
9 pages, 1972. Agricultural and biological chemistry
and Biological Chemistr
y), 34, 641, 1970].

[0005] The present inventors have previously found that konjac flour having an average molecular weight of 2,000 to 15,000 does not inhibit the absorption of useful minerals such as calcium and does not induce diarrhea even when overdosed. Invented and filed a water-soluble dietary fiber for foods and drinks comprising a decomposed product of polysaccharide (Japanese Patent Laid-Open No. 22-22 / 1990).
No. 2659. Hereinafter referred to as the earlier application).

[0006]

After filing the prior application, the present inventors conducted intensive research on the pharmacological action of the partial hydrolyzate of glucomannan derived from konjac of the prior application.
As a result, the average molecular weight having no polymer structure is 2,000.
The present inventors have discovered a novel fact that a specific glucomannan partial hydrolyzate of 0 to 5,000 has a blood cholesterol lowering effect.

Further, the present inventors have found that the average molecular weight is
The specific glucomannan partial hydrolyzate of from 2,000 to 5,000, in addition to its blood cholesterol-lowering effect, also has a secondary bile acid deoxycholic acid, which is known as a colorectal cancer promoter or mutagen, and Lithocholic acid (Toshimitsu Mitsuoka, “Metabolism of intestinal flora”, No. 140
Page, Academic Publishing Center, 1988).

[0008] The present invention has been completed based on the above-described novel findings.

It is an object of the present invention to provide a glucomannan partial hydrolyzate which does not have any of the above-mentioned drawbacks and problems found in konjac flour and has a blood cholesterol lowering effect and a colorectal cancer preventive effect. And

Another object of the present invention is to provide a blood cholesterol lowering agent having an average molecular weight of 2,000 to 50,000.
It is to provide a glucomannan partial hydrolyzate which is 00.

Another object of the present invention is to provide a glucomannan partial hydrolyzate having an average molecular weight of 2,000 to 5,000, which has a blood cholesterol lowering effect and a colorectal cancer preventing effect. is there.

Another object of the present invention is to provide a polymer having an average molecular weight of 2,0.
It is an object of the present invention to provide a colorectal cancer preventive agent comprising a glucomannan partial hydrolyzate of from 00 to 5,000 as an active ingredient.

[0013]

SUMMARY OF THE INVENTION The object (namely, object) of the present invention is that the average molecular weight is from 2,000 to 5,000.
Is a specific partial hydrolyzate of glucomannan derived from konjac (hereinafter simply having an average molecular weight of 2,000 to 5,
000 glucomannan partial hydrolyzate. ) Is achieved.

Hereinafter, the present invention will be described in detail. The glucomannan partial hydrolyzate having an average molecular weight of 2,000 to 5,000 in the present invention is produced as follows.

That is, commercially available konjac flour such as refined, medium and coarse flour, glucomannan separated from konjac flour, or konjac flour decolorized and deodorized with alcohol are used as starting materials. Partial hydrolysis (low molecular weight) of these starting materials can be performed by a known acid hydrolysis method or enzymatic decomposition method. In the acid hydrolysis, the side chain of the polysaccharide is degraded faster than the main chain (Japanese Patent Application Laid-Open (JP-A) No. 63-26).
In order to adjust the degree of decomposition, enzymatic decomposition is desirable. A commercially available enzyme having a function of hydrolyzing glucomannan can be used as the enzyme used for the enzymatic decomposition. Such enzymes include, for example, Aspergillus
Niger (Aspergillus niger), Trichoderma virido ( Trichoderma vir)
ide), Penicillium notatum (Penicil)
ium notatum), a microorganism belonging to the genus Streptomyces (Streptomyces sp.),
Rizopus niveus
u), Bacillus
circulans), mannanase of konjac tubers, and the like. Of these, endo-type enzymes that hydrolyze intramolecular β-glucoside bonds of glucomannan, particularly cellulases derived from microorganisms belonging to the genus Aspergillus, are desirable.

The pH and reaction time during the enzymatic decomposition have a great influence on the molecular weight of the product. That is, since a commercially available enzyme preparation is a mixture of an endo-type enzyme and an exo-type enzyme, an enzyme reaction is carried out under conditions that reduce the activity of the exo-type enzyme contained in the enzyme, and a reaction that minimizes the amount of released monosaccharides. The pH of the solution and the reaction time must be determined in advance by experiments. For example, as in Examples 1 to 3 described below, the reaction conditions are maintained at 40 to 60 ° C. for 4 to 16 hours. Next, the pH of the reaction solution was adjusted to 2 to 5, and the protein was removed at the same time as heating to inactivate the enzyme, the supernatant was collected, and activated carbon, a synthetic adsorbent, or an ion exchange resin was used.
Remove impurities. Further, if necessary, a monosaccharide can be removed or a desired molecular weight fraction can be collected by gel filtration using a UF membrane, a loose RO membrane, or Sephadex, concentrated, dried and powdered.

The partially hydrolyzed glucomannan having an average molecular weight of 2,000 to 5,000 according to the present invention can be directly orally ingested as it is. In this case, a partial hydrolyzate of glucomannan having an average molecular weight of 2,000 to 5,000 according to the present invention may be mixed with an excipient to prepare a formulation, and other blood cholesterol lowering agents or colorectal cancer prevention It can also be used as a preparation in combination with an agent.
Also, the glucomannan partial hydrolyzate can be added to various foods without changing their properties. In the latter case, it can be stably added not only to solid foods such as frozen desserts, breads and jellies, but also to liquid foods such as milk and fruit juice.

Next, the present invention will be described in detail with reference to test examples.

(Test Example 1) This test was conducted to examine the action of the hydrolyzate.

(1) Preparation of samples Feeds having the components shown in Table 1 were used. The basal feed is a standard feed in a conventional method, but the test feed contains 5% of the sucrose in the basal feed as described in Example 1 described below (average molecular weight: 2,000) and Example 2 described later. (Average molecular weight: 3,
000) and Example 3 described below (average molecular weight: 5,000).
0), a water prepared by the same method as Comparative Example 1 (average molecular weight: 600), Comparative Example 2 (average molecular weight: 15,000) described later, and Comparative Example 3 (average molecular weight: 7,000) described later. This is a test feed that has been replaced with a degradation product.

[0021]

[Table 1] *: Glucomannan partial hydrolyzate obtained in each of Examples and Comparative Examples

(2) Test Method Seven test animal groups, each group consisting of eight SD rats, were fed a test feed having the components shown in Table 1 and a basic feed for 21 days. Blood was collected from the tail vein at 7-day intervals, and heparin, an anticoagulant, was added.
Centrifugation was performed for 15 minutes to obtain plasma.

The plasma cholesterol level was measured using a total cholesterol measurement kit (Kyowa Medix, Determiner TC5).
55) and colorimetrically determined.

Further, on the last day of breeding, fresh feces were collected, freeze-dried, and bile acids were extracted by a conventional method. Bile acid was analyzed by HPLC using reverse-phase column chromatography to obtain 3α-hydroxysteroid dehydrogen.
The analysis was performed by the enzyme post-labeling method using R. genase.

(3) Test Results The test results are as shown in FIG. 1 and Table 2. The vertical and horizontal axes in the figure represent blood cholesterol and the number of days, respectively. In the figure,-●-is a basal feed administration group,-○-is a 5% administration group using the partial hydrolyzate of Example 1,- ◇-is a 5% administration group using the partial hydrolyzate of Example 2,-◆-is a 5% administration group using the partial hydrolyzate of Example 3,-□-
Is a 5% administration group using the partial hydrolyzate of Comparative Example 1,-△
-Is a 5% administration group using the partial hydrolyzate of Comparative Example 2,-
−- indicates a 5% administration group using the partial hydrolyzate of Comparative Example 3, respectively.

As is clear from FIG. 1, in the group to which the hydrolyzate of the present invention was administered, no effect was observed for 7 days after the administration, but a marked decrease in blood cholesterol was observed after 7 days. . However, average molecular weight 600,
No effect was observed in the hydrolyzate having an average molecular weight of 7,000 and an average molecular weight of 15,000.

Table 2 shows the amounts of secondary bile acids deoxycholic acid and lithocholic acid produced.

From the results in Table 2, the following was found. That is, the glucomannan partial hydrolyzate administration group of Examples 1, 2 and 3 described below is a basal feed administration group, Comparative Example 1 described below,
The amount of secondary bile acids was reduced as compared with the glucomannan partial hydrolyzate administration groups 2 and 3. In addition, when the glucomannan hydrolyzate prepared by another method was used, almost the same results were obtained.

[0029]

[Table 2]

[0030]

Comparative Example 1 Glucomannan partial hydrolysis was carried out in the same manner as in Example 1 below, except that the time of the enzyme reaction with cellulase was set to 24 hours and the pH during heating was adjusted to 2.0. About 2,500 g of the product was obtained. The average molecular weight of this partial hydrolyzate was 600.

[0031]

[Comparative Example 2] The enzymatic reaction time by cellulase was 3.5.
A glucomannan partial hydrolyzate purified by the same method as in Example 3 described below except that
00 g were obtained. The average molecular weight of this partial hydrolyzate is 1
It was 5,000.

[0032]

Comparative Example 3 Glucomannan partial hydrolysis was carried out in the same manner as in Example 1 below, except that the time of the enzyme reaction with cellulase was set to 8 hours and the pH during heating was adjusted to 3.0. About 980 g of the product was obtained. The average molecular weight of this partial hydrolyzate was 7,000.

Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples.

[0034]

Example 1 A commercially available cellulase Amano (manufactured by Amano Pharmaceutical Co., Ltd., fibrous saccharifying power 15.0) was added to 40 l of a phosphate buffer (pH 6.5).
(00 U / g), and 120 kg of commercially available konjac flour was stirred and dissolved while heating to 50 ° C., kept at 50 ° C. for 16 hours, and then adjusted to pH 4.5 with hydrochloric acid.
Heated at ° C for 10 minutes. The residue was separated from the reaction solution by diatomaceous earth filtration, and the supernatant was used for activated carbon (500 ml) and cation exchange resin Dowex (50 W × 8 (H ⁺ ), 1,000 ml).
And anion exchange resin Dowex 1 × 8 (OH ^-)
The mixture was passed through 4,000 ml in order to purify, desalted, concentrated, spray-dried, and partially hydrolyzed with glucomannan of about 2,550.
g was obtained. The average molecular weight of this partial hydrolyzate is 2,000
It was 0.

[0035]

Example 2 A glucomannan partial hydrolyzate was prepared in the same manner as in Example 1 except that the time of the enzyme reaction with cellulase was set to 12 hours, and the pH during heating was adjusted to 5.0. 2,540 g were obtained. The average molecular weight of this partial hydrolyzate was 3,000.

[0036]

Example 3 60 g of commercially available cellulase Nagase (manufactured by Nagase Seikagaku Kogyo Co., Ltd., with a saccharifying power of 1,000 U / g) was added to 90 l of an acetate buffer (pH 4.5), and the mixture was heated to 60 ° C. and marketed Dissolve 10.0 kg of konjac flour with stirring.
Hold at 0 ° C. for 5 hours, then adjust to pH 4.5 with hydrochloric acid,
Heated at 95 ° C. for 10 minutes. The residue was separated from the reaction mixture by diatomaceous earth filtration, and the supernatant was separated from activated carbon (2,000 ml) and a cation exchange resin Dowex 50W × 8 (H ⁺ ) 2.5.
00 ml and anion exchange resin Dowex 1 × 8 (O
H ⁻ ) was sequentially passed through 6,000 ml, desalted and purified, concentrated, spray-dried, and partially hydrolyzed with glucomannan partially
130 g were obtained. The average molecular weight of this partial hydrolyzate was 5,000.

[0037]

The effects provided by the present invention are as follows.

(1) The glucomannan partial hydrolyzate of the present invention having an average molecular weight of 2,000 to 5,000 has a blood cholesterol lowering effect.

(2) The glucomannan partial hydrolyzate of the present invention having an average molecular weight of 2,000 to 5,000 has an inhibitory effect on secondary bile acid production, and is therefore effective in preventing colon cancer.

(3) The partial hydrolyzate of glucomannan having an average molecular weight of 2,000 to 5,000 according to the present invention does not affect the sensory characteristics of food even when it is added to food.

[Brief description of the drawings]

FIG. 1 shows the relationship between the days of breeding and blood cholesterol.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-22659 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61K 31/715 C08B 37/00

Claims (1)

(57) [Claims] An agent for preventing colorectal cancer comprising as an active ingredient a partially hydrolyzed glucomannan having an average molecular weight of 2,000 to 5,000, which is obtained by enzymatically decomposing and purifying konjac-derived glucomannan.