JPH07196676A - Method for producing inositol phosphate - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a method for easily producing inositol phosphate from phytic acid and / or a salt thereof at high yield and at low cost. [Structure] A solution containing phytic acid and / or a salt thereof is partially dephosphorized by a method such as acid decomposition, enzymatic decomposition, or thermal decomposition to give inositol phosphoric acid having 1 to 5 phosphoric acid groups. The resulting inositol phosphate-containing solution is electrodialyzed to remove inorganic components such as phosphoric acid mixed in the solution and purified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing inositol phosphate, and more particularly to a method for producing inositol 1-5 phosphate having 1 to 5 phosphate groups bonded to inositol.

[0002]

2. Description of the Related Art Phytic acid is an inositol to which 6 phosphate groups are bound, and is abundantly contained as a phosphate storage substance in plant foods such as cereals and beans, which humans have a long eating experience with. Has been done.

Phytic acid and its salts have been known to inhibit the body's absorption of minerals, especially calcium (Sinoda, S. and Yoshida, T .: Nutr. Rep. Int., 40.
909 (1989)). However, it was found that inositol phosphate having a phosphate group number of 1 to 5 by partially dephosphorylating phytic acid and its salt has a calcium absorption promoting effect (Japanese nutrition. Journal of Food Science Vol.46 N
o.1 83-88 (1993)), it has been proposed to use it as a calcium absorption promoter (Japanese Patent Application No. 3-75811).
No., JP-A-4-270296).

Inositol phosphoric acid having 1 to 5 phosphoric acid groups is prepared by partially dephosphorizing a solution containing phytic acid and / or a salt thereof and then removing inorganic components such as by-produced free phosphoric acid. Obtained by removing. In this case, if the purification is not sufficient, not only the product becomes sour due to the phosphoric acid remaining in the solution, but also this phosphoric acid reacts with calcium ions to form an insoluble calcium salt, which inhibits the absorption of calcium. There are problems such as fear.

Japanese Patent Application No. 3-75 discloses a method for purifying inositol phosphate from a solution obtained by dephosphorizing phytic acid.
In No. 811, a method is used in which inositol phosphate is adsorbed to the resin by liquid chromatography using an ion exchange resin and then eluted from the resin with a dilute hydrochloric acid solution or the like. Further, in JP-A-4-270296, a method for separating phosphoric acid by calcium fractional precipitation utilizing the difference in solubility of phytic acid, inositol 1-5 phosphoric acid, and calcium salts of phosphoric acid in water and alcohol. Has been adopted.

[0006]

However, in the method of treating a mixed solution of inositol phosphate and phosphoric acid by liquid chromatography, the amount that can be treated at one time is limited and the treatment takes a long time. It wasn't the right way.

Further, the method by the calcium fractional precipitation is
Not only is the precipitation of calcium salts very time consuming,
It was difficult to completely separate inositol phosphate and phosphoric acid because there was not much difference in the solubility of each calcium salt. Further, since a large amount of alcohol is required, there is a problem that the production cost of inositol phosphate becomes very high.

Therefore, an object of the present invention is to provide a method for easily producing inositol phosphoric acid having 1 to 5 phosphoric acid groups from phytic acid and / or a salt thereof at a high yield and at a low cost. It is in.

[0009]

In order to achieve the above object, the method for producing inositol phosphates of the present invention is a method in which a solution containing phytic acid and / or a salt thereof is partially dephosphorized to produce phosphoric acid. The method is characterized by including a step of producing inositol phosphate having a base number of 1 to 5 and a step of purifying the solution containing the inositol phosphate by electrodialysis.

The present invention will be described in more detail below with reference to preferred embodiments.

First, the step of producing inositol phosphoric acid having 1 to 5 phosphoric acid groups will be described. The phytic acid and / or its salt as a raw material is not particularly limited, and various commercially available products may be used. You may prepare from the natural product containing these.

As a product prepared from a natural product, for example, a dispersion obtained by dispersing natural bran, germ, bran or the like in water or a dilute acid solution, or a product obtained by extracting phytic acid and / or its salt from this dispersion Further, it is possible to use a product obtained by removing insoluble substances from this extract.

To partially dephosphorylate a solution containing the above phytic acid and / or salt thereof, for example, acid decomposition,
Means such as enzymatic decomposition and thermal decomposition are adopted. In the case of acid decomposition, it is preferable to use an inorganic acid, and it is more preferable to use hydrochloric acid. In the case of enzymatic degradation, it is preferable to add phytase or fosterase, or wheat bran containing these enzymes, for treatment. Furthermore, in the case of thermal decomposition, it is preferable to perform heating by heating under pressure using an autoclave or the like to a temperature of 100 ° C. or higher.
After dephosphorization, if necessary, decantation,
It is preferable to remove insoluble matter by a method such as centrifugation or filtration.

Next, the electrodialysis treatment step for removing inorganic components such as free phosphoric acid from the inositol phosphate-containing solution will be explained. This electrodialysis treatment involves separation membranes such as ion exchange membranes and molecular sieve membranes. It is preferable to carry out using the electrodialysis device used.

FIG. 1 shows an example of such an electrodialysis device. That is, between the anode 1 and the cathode 3,
A large number of anion-exchange membranes 5 and cation-exchange membranes 6 are alternately arranged, and when the anion-exchange membrane 5 and the cation-exchange membrane 6 are arranged in this order from the anode 1 side, the liquid to be treated is Flowing desalination chamber 7, cation exchange membrane 6, anion exchange membrane 5
The space between the films arranged in this order is an ion recovery chamber 8 in which cations and anions in the liquid to be treated are collected.

In the anode chamber 2 and the cathode chamber 4, the electrode liquid flow path 1 is provided.
The electrode liquid is circulated by the pump 11 through 0, and the liquid to be treated, that is, the inositol-phosphate-containing solution is circulated in the desalination chamber 7 by the pump 13 through the liquid passage 12 to be treated. Further, a recovery liquid is circulated in the ion recovery chamber 8 by a pump 15 through a recovery liquid flow path 14.

When a voltage is applied between the anode 1 and the cathode 3, the cations in the inositol phosphate-containing solution are
The anions in the inositol phosphate-containing solution are collected in the recovery chamber 8 through the cation exchange membrane 6, and are collected in the recovery chamber 8 through the anion exchange membrane 5. Although inositol phosphate itself is also ionized, it cannot pass through the ion exchange membrane and remains in the desalting chamber 7 because of its large molecular weight. In this way, phosphate ions and the like in the inositol phosphate-containing solution are removed, and a purified inositol phosphate-containing solution can be obtained from the desalting chamber 7 side.

In the above, the ion exchange membranes 5 and 6 have a molecular weight cutoff of 30 because they block permeation of inositol phosphate itself and selectively permeate ions such as phosphoric acid.
Ion exchange membranes or molecular sieve membranes of 0 or less are preferably used. As a commercially available product, for example, "AC110" (trade name, manufactured by Asahi Kasei Co., Ltd.) or the like can be preferably used.

An acidic solution, an inorganic salt solution, or the like is used as the ion recovery solution. It is preferable to use a hydrochloric acid solution as the acidic solution, and its concentration is 0.05 to 3.5.
% Is preferred. A salt solution is preferably used as the inorganic salt solution, and its concentration is preferably 0.05 to 3.5%.

The purified inositol-phosphate-containing solution thus recovered from the desalting chamber 7 side is concentrated and crystallized as necessary to be commercialized.

[0021]

According to the present invention, a solution containing phytic acid and / or a salt thereof is partially dephosphorized, and then electrodialyzed to purify the solution, whereby inorganic substances such as phosphoric acid mixed in the solution are mixed. The components can be removed efficiently. Therefore, inositol phosphoric acid having 1 to 5 phosphoric acid groups can be easily produced at low cost.

[0022]

【Example】

Example 1 Commercially available 50% phytic acid (Daiichi Pharmaceutical Co., Ltd.) 200
500 g of water was added to g, and the pH was adjusted to 6.0 with a 20% aqueous sodium hydroxide solution. This solution was added to the method of Nagai et al. (Nagai, Y. and Funahashi, S .: Agric. Biol. Chem.,
26, 794 (1962)) and 40,000 U of phytase prepared from wheat bran according to 26, 794 (1962)) or 10 g of a commercially available phytase enzyme agent (manufactured by Amano Pharmaceutical Co., Ltd.) was added to make 1 liter, and then the enzyme was added at 40 ° C. for 6 to 48 hours. The reaction was carried out. The reaction mixture was heated in boiling water for 30 minutes to inactivate the enzyme, then 5000
Insoluble matter was removed by centrifugation at rpm for 15 minutes, and a commercially available electrodialyzer "Micro Acylyzer G3" (trade name,
Asahi Kasei Co., Ltd.) was used for purification to remove free phosphoric acid and the like to obtain a solution containing inositol phosphoric acid having 1 to 5 phosphoric acid groups. As the membrane cartridge of the electrodialysis device, a membrane having a molecular weight cutoff of 100, "AC
110 "(trade name, manufactured by Asahi Kasei Co., Ltd.) was used, and 0.3% hydrochloric acid or 0.3% sodium chloride aqueous solution was used as the ion recovery liquid.

FIG. 2 shows the relationship between the operating time of the electrodialyzer and the amount of phosphoric acid in the sample solution. In the figure, □ is the result when 0.3% hydrochloric acid was used as the ion recovery solution, and ◯ is the result when 0.3% sodium chloride aqueous solution was used as the ion recovery solution. As is clear from the figure, it was found that phosphoric acid was effectively removed from the sample liquid regardless of which ion recovery liquid was used.

Example 2 To 2.5 kg of rice bran, 12.5 liters of 0.3N hydrochloric acid was added, stirred for 1 hour and then subjected to a continuous centrifuge to obtain about 10 liters of the extract. A 20% aqueous sodium hydroxide solution was added to this extract to adjust the pH to 8.0 and
After standing for a time, centrifugation was performed again to obtain a crude phytin precipitate. To this precipitate, add 500 ml of 10% hydrochloric acid,
In the autoclave, the decomposition reaction under pressure at 121 ° C. for 3 hours was performed, and then the activated carbon treatment was performed. After dehydrochlorinating and dephosphorizing this reaction solution with an electrodialyzer "Micro Acylyzer EX3" (trade name, manufactured by Asahi Kasei Co., Ltd.), the reaction solution is concentrated to give inositol phosphorus having 1 to 5 phosphate groups. A solution containing the acid was obtained. As the membrane cartridge of the electrodialysis device, "AC110" (trade name, manufactured by Asahi Kasei Co., Ltd.), which is a membrane with a molecular weight cutoff of 100, was used, and as the ion recovery liquid, 0.3% hydrochloric acid or 0.3% was used. %
An aqueous solution of sodium chloride was used.

[0025]

As described above, according to the present invention,
Inorganic components such as by-produced free phosphoric acid can be efficiently removed from a solution obtained by partially dephosphorizing phytic acid and / or its salt. Therefore, the number of phosphoric acid groups is 1 to 5
Individual inositol phosphates can be produced easily and at low cost.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an example of an electrodialysis device used in the present invention.

FIG. 2 is a chart showing a relationship between an operating time and an amount of phosphoric acid in a solution when an inositol phosphoric acid-containing solution is electrodialyzed.

[Explanation of symbols]

 1 Positive Electrode 2 Positive Electrode Chamber 3 Negative Electrode 4 Negative Electrode Chamber 5 Anion Exchange Membrane 6 Cation Exchange Membrane 7 Desalination Chamber 8 Ion Collection Chamber 10 Electrode Liquid Flow Path 12 Processed Liquid Flow Path 14 Recovered Liquid Flow Path 11, 13, 15 pump

Claims (4)

[Claims] 1. A step of partially dephosphorylating a solution containing phytic acid and / or a salt thereof to produce inositol phosphoric acid having 1 to 5 phosphoric acid groups, and the inositol phosphoric acid-containing solution. And the step of purifying the product by electrodialysis. 2. The method for producing inositol phosphate according to claim 1, wherein the solution containing phytic acid and / or a salt thereof is prepared from at least one selected from bran, germ and bran. 3. The method according to claim 1, wherein the solution containing phytic acid and / or its salt is partially dephosphorized by any one method selected from acid decomposition, enzymatic decomposition and thermal decomposition. A method for producing inositol phosphate. 4. The inositol phosphate according to claim 1, wherein the solution containing inositol phosphate is electrodialyzed using an ion exchange membrane having a molecular weight cut off of 300 or less or a separation sieve membrane. Manufacturing method.