JPH0649053A - Production of proanthocyanidin - Google Patents

Abstract

PURPOSE:To recover proanthocyanidin at high rate and in high purity from a proanthocyanidin-contg. solution. CONSTITUTION:A proanthocyanidin-contg. solution is adsorbed onto a polystyrene-based adsorptive resin, and the resulting resin is dried and then leached using a solvent of low polarity, thus recovering the objective proanthocyanidin.

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 proanthocyanidins which are effectively used as antioxidants for foods or for fading color components, or as physiologically active substances.

[0002]

2. Description of the Related Art JP-A-63-1626 as a prior art
No. 85 discloses a method for recovering and producing proanthocyanidins from a solution containing proanthocyanidins, in which a solution containing proanthocyanidins is first adsorbed on a polystyrene-based adsorption resin, and then the adsorption resin is washed with water or the like. Then, a method is proposed in which elution is carried out at a temperature of 60 ° C. or higher with a polar solvent such as water or ethanol.

[0003]

However, this prior art method for producing proanthocyanidins uses a polar solvent at a temperature of 60 ° C. or higher in order to maintain a high recovery rate of proanthocyanidins from a solution. In addition to the need for a heating device and its heat source, it is difficult to handle at a high temperature in a low boiling point polar solvent because it is a substance to be eluted and must be strictly temperature-controlled at a high temperature. However, there is a problem that the manufacturing process and the manufacturing equipment become complicated, resulting in a large increase in manufacturing cost.

Moreover, in the above-mentioned prior art method, the adsorbent resin after being washed with water or the like is transferred to elution using a polar solvent at a temperature of 60 ° C. or higher, which is the next step, in a wet state. In a polar solvent such as ethyl acetate, which can be dissolved only in a fixed ratio in water, since the affinity with the adsorbing resin in a wet state is poor, the yield of proanthocyanidins is low. There was also the problem of being extremely low.

Further, in the above-mentioned method of the prior art, in order to increase the purity of the recovered proanthocyanidin, the adsorbed resin after adsorption is washed with water or the like,
The impurities adhering to the surface of the adsorption resin are removed, but if this washing is incomplete, in the subsequent elution step, the impurities will elute in the polar solvent together with proanthocyanidin. However, the purity of the collected proanthocyanidins will be reduced.

For this reason, the cleaning with water or the like must be carried out completely and with sufficient time and effort, which results in a significant increase in cost. The present invention provides a method for achieving proanthocyanidins from a solution containing proanthocyanidins, at a high recovery rate, and recovering / manufacturing with high purity at a low cost. As a result of various experiments and examinations for achieving the above object, the present invention has been completed.

[0007]

Means for Solving the Problems That is, the present invention is that a solution containing a proanthocyanidin is adsorbed on a polystyrene-based adsorbent resin, and then the adsorbent resin is once dried and then a polar solvent having a small polarity is used. It was decided to elute. The proanthocyanidins in the present invention are contained in most of the plants existing in the natural world, and as a constitutional unit, a low polymer having a degree of polymerization of flavan-3-ol of 2 to 6 is referred to. The following general formula,

[0008]

[Chemical 1]

[0009] Further, the proanthocyanidin-containing solution that is the raw material may be any as long as it contains proanthocyanidins, for example,
A raw material can also be a solution containing impurities such as proteins, such as astringent cut water of beans such as red beans or boiled juice of beans discharged from the bean jam manufacturing process.

Further, as the polystyrene-based adsorption resin, for example, one commercially available under the trade name "Sepa beads SP-850" from Mitsubishi Kasei Co., Ltd. is used.

[0011]

[Operation] After adsorbing the proanthocyanidin-containing solution, the adsorbent resin is once dried. The drying of the adsorption resin is carried out at a temperature of about 80 ° C. or lower in order to avoid deterioration of the proanthocyanidins adsorbed on the adsorption resin. By drying the adsorption resin, the recovery rate of proanthocyanidins can be maintained at a high value without performing the subsequent elution step at a high temperature, as described below and in the Examples.

Moreover, after the adsorption resin is adsorbed, once it is dried, impurities such as proteins adhering to the adsorption resin undergo denaturation, so that in the subsequent elution step, the adsorbent resin against the polar solvent is removed. Since the solubility of the impurities becomes low, the purity of the recovered proanthocyanidins can be prevented from being lowered by the impurities contained in the raw material proanthocyanidin-containing solution. In other words, the purity of the proanthocyanidins is the adsorption step. The degree of change depending on the presence or absence of the subsequent washing step and the degree of washing can be made lower than in the case of the prior art.

Further, after the adsorption resin is subjected to the adsorption step, once it is dried, the surface of the adsorption resin becomes in a dry state.
Even if a polar solvent such as ethyl acetate that can be dissolved only in a fixed ratio in water is used, it is possible to retain a high affinity for the adsorption resin, in other words, in the elution step. Therefore, it becomes possible to use a polar solvent that can be dissolved only in a fixed ratio in water.

To elute the proanthocyanidins from the adsorption resin, a polar solvent having a low polarity is used. That is, it is not suitable to use a polar solvent having high polarity such as water or methanol among polar solvents, and it is suitable to use a polar solvent having low polarity such as ethanol or acetone. In this case, when ethanol is used as the polar solvent, its concentration is preferably 40% (v / v) or more.

On the other hand, ethyl acetate, butanol, propanol or the like is suitable as the polar solvent which can be dissolved in water at a fixed ratio. Further, the temperature during the elution step is 60 ° C. as in the prior art.
It is not necessary to make the temperature higher than the above, and it is carried out at a low temperature of 30 ° C. or lower. Since the elution step at this low temperature makes it possible to make the recovery rate of proanthocyanidins substantially the same as in the prior art. Yes, i.e., the elution step can be carried out at a lower temperature, so as in the prior art,
It does not require temperature control to reach high temperature,
It does not cause difficulty in handling when a low boiling point polar solvent is used.

Particularly, in this elution step, as described above,
By using a polar solvent such as ethyl acetate which can be dissolved only in a fixed ratio in water, the recovery rate of proanthocyanidins from a solution containing proanthocyanidins is significantly increased as compared with the case of the prior art. It is possible.

[0017]

As described above, according to the present invention, it is possible to recover and produce proanthocyanidins with a high recovery rate and a high purity from a solution containing a proanthocyanidin which is a raw material. Without doing
Therefore, there is an effect that it can be achieved reliably without causing an increase in cost.

In addition to the above effects, the purity of the collected proanthocyanidins can be further improved by adding a washing step as in "claim 2." Furthermore, according to "Claim 3", in addition to the above-mentioned effect, alteration of the proanthocyanidins adsorbed to the adsorption resin can be prevented when the adsorption resin is dried. Therefore, the proanthocyanidins are dried by drying the adsorption resin. It is possible to avoid a decrease in the recovery rate of.

On the other hand, according to "Claim 4", proanthocyanidins can be recovered from the soaking water of beans or the astringent cutting water discharged from the manufacturing process of bean jam or the broth of beans, so that the production cost is further reduced. Has the effect that can.

[0020]

EXAMPLES Examples of the present invention will be described below. Example 1 Obtained by immersing 10 kg of dried azuki beans in 25 liters of water for about 16 hours 15
1 liter of immersion water was used as the starting solution containing proanthocyanidins.

To this 15 liters of immersion water, add 750 cc of polystyrene-based adsorption resin commercially available under the trade name "Sepa beads SP-850" from Mitsubishi Kasei Co., Ltd. and stir at room temperature for about 2 hours. The proanthocyanidins in the immersion water are adsorbed on the adsorption resin by. Next, the adsorbed resin was separated (water drained) with a 80-mesh sieve, and then rapidly dried at a temperature of 70 ° C. or lower with a vacuum evaporation dryer to obtain a dried adsorbent resin. .

Each of the eight dried adsorbent resins was placed in a stoppered Erlenmeyer flask with an internal volume of 200 cc and prepared separately.
Add g each. Furthermore, in each stoppered Erlenmeyer flask,
When 70 cc of the polar solvent shown in "Table 1" and "Table 2" is added, and the elution is performed by shaking (shaking) for 2 hours at the temperature shown in "Table 1" and "Table 2". I did a test to say.

However, "water-ethyl acetate" in "Table 2" is a solution of ethyl acetate dissolved in water to a saturated state. On the other hand, the adsorption resin having adsorbed proanthocyanidins was once washed with water, then, without being dried, in a wet state (water content of 63%), 20 g of each was placed in each of eight stoppered Erlenmeyer flasks, Furthermore, 70 cc of the polar solvent shown in "Table 1" and "Table 2" (however, in the case of ethanol, ethanol was added so that the final concentration was each concentration) was added to each of the ground-in stopper Erlenmeyer flasks. A test was conducted in which the mixture was added, and at the temperatures shown in "Table 1" and "Table 2", it was dissolved by shaking (swinging) for 2 hours.

Then, the eluate in each of the stoppered Erlenmeyer flasks described above was evaporated in a vacuum evaporator at a temperature of 60 ° C. or lower to obtain a crude proanthocyanidin powder. Then, the amount of the proanthocyanidin low polymer in each of the crude proanthocyanidin powders was adjusted by the hydrochloric acid-butanol method [W.
E. Hillis: J. Sci. Fd. Agric. (1959)], the result measured as the amount of leucoanthocyanin "OD ₅₅₀ nm" was as shown in "Table 1" and "Table 2".

[0025]

[Table 1]

[0026]

[Table 2]

As is clear from "Table 1", when the adsorbent resin is not dried, that is, when the adsorbent resin is in a wet state (prior art), in order to improve the recovery of the proanthocyanidin low polymer, the elution Although it is necessary to raise the temperature, when the adsorption resin is dried as in the present invention,
Even if the elution temperature was not raised, the recovery rate of the proanthocyanidin low polymer could be made approximately the same as in the case of the prior art.

That is, in the case of a polar solvent having a low polarity, the proanthocyanidin low polymer is recovered at a high recovery rate without raising the elution temperature by once drying the adsorption resin before the transition to the elution step. It was possible. Further, as is clear from "Table 2", in the method of elution of the adsorbed resin in a wet state at a high temperature as in the prior art, no improvement in the recovery rate was observed, and rather the elution at a low temperature was observed. Was more effective in improving the recovery rate as a result.

On the other hand, in the method of once drying the adsorption resin as in the present invention, the recovery rate of the proanthocyanidin low polymer is substantially constant regardless of the elution temperature, which is higher than that in the prior art. It could be greatly improved. In addition, since the polar solvent used here is a low boiling point polar solvent, handling becomes difficult at high temperature elution, so low temperature elution is preferable. [Example 2] 7.5 kg of broth prepared by boiling 5 kg of dried azuki beans in 15 liters of water was subjected to the test as a solution containing proanthocyanidins. This broth contains, in addition to proanthocyanidins, a large amount of impurities such as proteins and starch.

To the above-mentioned broth, 375 cc of polystyrene-based adsorption resin commercially available under the trade name "Sepa beads SP-850" from Mitsubishi Kasei Co., Ltd. was added and the adsorption was carried out by stirring at room temperature for about 2 hours. Adsorb proanthocyanidins in the broth to the resin. Next, the adsorbent resin is washed with 1.5 liters of water at 25 ° C., drained, and then dried in a vacuum evaporation type drier.
A dry adsorption resin was obtained by rapidly drying at a temperature of 0 ° C. or lower.

7.4 g of each of the dried adsorbent resins is placed in each of six separately prepared Erlenmeyer flasks with an internal volume of 200 cc. Furthermore, to each of the ground-in stopper Erlenmeyer flasks, 70 cc of the polar solvent shown in "Table 3" was added,
At the temperature shown in "Table 3", a test of elution by shaking (shaking) for 2 hours was performed.
On the other hand, the adsorption resin having adsorbed proanthocyanidin was once washed with water and then put into each of three three-stopper Erlenmeyer flasks with 20 g each in a wet state (water content 63%) without being dried. Further, to each of the ground-in stopper Erlenmeyer flasks, 70 cc of the polar solvent shown in "Table 3" (however, in the case of ethanol, ethanol was added so that the final concentration was each concentration) was added, and " At the temperature shown in "Table 3," a test was conducted in which elution was carried out by shaking (shaking) for 2 hours.

Then, the eluate in each Erlenmeyer flask with a ground stopper was evaporated at a temperature of 60 ° C. or lower in a vacuum evaporator to obtain a crude proanthocyanidin powder. Then, the amount A of the proanthocyanidin low polymer in each of the crude proanthocyanidin powders,
The amount B of the protein and the ratio of the protein to the proanthocyanidin low polymer, that is, the degree of purification A / B were calculated, and the results are shown in "Table 3".

The amount A of the proanthocyanidin low polymer was measured by the hydrochloric acid-butanol method as the amount of leucoanthocyane "OD ₅₅₀ nm", and the amount B of the protein was measured by Lowry-Folin Method Lowry, O.M. H. etc:
J. The amount of bovine serum albumin was measured as "OD ₆₆₀ nm" by Biol. Chem. (1951).

[0034]

[Table 3]

The red bean juice used in this third embodiment is
In order to selectively recover proanthocyanidins from this broth by containing a large amount of impurities in addition to proanthocyanidins, the major factors are the removal of sugars such as starch, which is the main impurity, and the removal of proteins. Becomes Of these, carbohydrates are difficult to dissolve in solvents other than water, and can be easily removed.However, in the case of proteins, there are all types of proteins, from hydrophilic to hydrophobic, It cannot be easily removed.

Therefore, in order to study a method for selectively recovering proanthocyanidins, the degree of purification of proanthocyanidins was compared by a value obtained by dividing the amount A of a proanthocyanidin low polymer by the amount B of proteins.
The results are shown in "Table 3", and the prior art method of eluting the wet resin at a high temperature shows a significant increase compared to the method of eluting from the dry resin as far as the degree of purification of proanthocyanidins is concerned. It turns out to be inferior.

On the other hand, when eluting from the dry resin, it was found that the degree of purification of proanthocyanidins can be improved by using a polar solvent having a low polarity. That is, in order to recover proanthocyanidins from a solution containing proanthocyanidins containing impurities such as proteins, the adsorption resin is once dried before elution and then at a low temperature,
By eluting with a polar solvent having low polarity, proanthocyanidins can be recovered with high recovery and high purity. [Example 3] 6 kg of water was added to 3 kg of dried products and heated, and 3 liters of astringent water when astringent cutting was performed were subjected to the test.

With respect to 3 liters of the astringent water, 150 cc of polystyrene-based adsorbent resin marketed by Mitsubishi Kasei Co., Ltd. under the trade name "Sepa beads SP-850" was used.
Then, the proanthocyanidin is adsorbed on the adsorption resin by stirring for about 2 hours at room temperature. Then, the adsorbent resin is washed with 1 liter of water to remove most impurities, and then rapidly dried at a temperature of 70 ° C. or lower in a vacuum evaporation dryer.

Then, the dried adsorption resin was swollen in 300 cc of ether and then the inner diameter was 2.1 cm.
It was packed in a glass column with a length of 45 cm, and in this state,
3. In the glass column, add 300 cc of ether.
A low molecular weight phenolic substance such as catechins and pigments and hydrophobic impurities are removed by flowing at a speed such that the entire amount passes in 5 minutes.

Then, 3 liters of water-ethyl acetate was caused to flow in the glass column at the same rate as above to elute proanthocyanidins, and then, at a temperature of 60 ° C. or lower in a vacuum evaporator. By evaporating
3.79 g of crude proanthocyanidin powder was obtained.

Claims (4)

[Claims] 1. A solution containing a proanthocyanidin is adsorbed on a polystyrene-based adsorption resin, and then the adsorption resin is
A method for producing proanthocyanidins, which comprises once drying and then eluting with a polar solvent having a small polarity. 2. A solution containing a proanthocyanidin is adsorbed on a polystyrene-based adsorption resin, and then the adsorption resin is
A method for producing proanthocyanidins, which comprises washing, drying, and then eluting with a polar solvent having a small polarity. 3. The method for producing proanthocyanidins according to claim 1, wherein the adsorption resin is dried at a temperature of 80 ° C. or lower. 4. The method according to claim 1, wherein the solution containing proanthocyanidin is immersion water or astringent water of beans discharged from the manufacturing process of bean jam, or broth of beans.
The method for producing proanthocyanidins according to 1.