JPH0631208B2 - Method for producing proanthocyanidins - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for efficiently producing proanthocyanidins useful as a raw material for producing antioxidants such as foods and cosmetics and pharmaceuticals.

[Conventional technology]

As a conventionally known method for separating proanthocyanidins, for example, a column chromatography method using a dextran derivative such as Sephadex LH-20 as a carrier [RS Tom
Pson et al., J. Chem. SoC. Perkin I, No. 11, 1387 (1972)]
Column chromatography method using polyamide as a carrier [JP Van Buren et al., J. Food Sci., Vol. 31, 964 (196
6)], or a countercurrent partitioning method, eg, by countercurrent partitioning between water and ethyl acetate [Andrew GH Lea, J. Sci. Fd Agr.
ic., vol.29, 471-477 (1978)] and the like.

[Problems to be solved by the invention]

Among the above-mentioned separation methods, the method using a dextran derivative has the drawback that the cost of the derivative is extremely high and that it takes a long time to elute the target substance. Although the target substance is adsorbed to the resin, it has the drawback that the amount of proanthocyanidin to be eluted is extremely small or very small, and in the countercurrent distribution method, a solvent having extremely high flammability is used. However, there are drawbacks such as complicated and dangerous operations.

[Means for solving problems]

In view of the above circumstances, the present inventors have made extensive studies to select a separation method useful for efficiently separating proanthocyanidins, and as a fractionation separation membrane, a molecular weight cutoff of 5000 or less is an ultrafiltration membrane. And / or it was found that high-purity proanthocyanidins can be obtained extremely efficiently and by a simple operation by treating with a reverse osmosis membrane having a salt exclusion rate of 30% or less, and the present invention has been completed. It was

That is, the present invention provides a proanthocyanidin-containing solution with an ultrafiltration membrane having a molecular weight cutoff of 5,000 or less and / or a salt exclusion ratio of 30.
% Or less after treatment with reverse osmosis membrane
A method for producing proanthocyanidins, which comprises collecting 0 fractions.

Hereinafter, the present invention will be described in detail.

The proanthocyanidins referred to in the present invention are a group of condensed tannins present in various plants, that is, a compound group in which flavan-3-ol or flavan-3,4-diol is bonded as a constituent unit by condensation or polymerization,
These are given this name because they produce anthocyanidins such as cyanidin, techfinidine, and pelargonidin by acid treatment.

Therefore, as the proanthocyanidin, a dimer, a trimer, a tetramer of the above structural unit, a proanthocyanidin such as a polymer procyanidin, a prodelphinidin, and a properargonidin having 20 or less monomers, and stereoisomers thereof are used. All included, the following general formula (In the formula, R ₁ is hydrogen or a hydroxyl group, R ₂ , R ₃ , and R ₄ are hydrogen, a hydroxyl group, or a methoxyl group, and R ₅ is hydrogen, a galloyl group, or a glycopyranosyl group). It is a 2-20 mer etc. which made -3,4-diol a structural unit.

First, the proanthocyanidin-containing liquid used in the present invention is
Any solution may be used as long as it contains a proanthocyanidin, for example, an aqueous extract of fruits such as apple, bud, persimmon, and cranberry, red beans, submerged liquid of beans such as black soybean,
Hydrous alcoholic extract of medicinal herbs such as rhubarb, mahuang, and Yangmei peel,
Alternatively, a hydroalcoholic solution of a proanthocyanidin synthesis reaction product or the like may be used, and the amount of proanthocyanidins in these contained liquids is preferably adjusted to about 10 p.pm or more in advance.

If necessary, vitamin C, sorbic acid, sulfurous acid, potassium metabisulfite, etc. may be added to the above-mentioned proanthocyanidin-containing liquid in an appropriate amount, for example, about 20 to 2000 p.pm, for the purpose of preventing oxidative deterioration and antiseptic.

Next, as the ultrafiltration membrane having a molecular weight cut off of 5000 or less used in the present invention, for example, ultrafiltration membrane module SEP-1013
(Manufactured by Asahi Kasei Corporation), ultrafiltration membrane DUY-HH, diamond filters G-05H, G-01T, G-05T (all manufactured by ULVAC SERVICE), diaflow membrane UM05, UM2, DM5 (all are Amicon. Far East Co.) or the like, or as an ultrafiltration device equipped with the above ultrafiltration membrane, TCD-40, TAD-40, B-
28, P-28 (both manufactured by Daicel Chemical Co., Ltd.) and the like. Examples of reverse osmosis membranes having a salt rejection rate of 30% or less include reverse osmosis module DRS-10 (manufactured by Daicel Chemical Co., Ltd.) and reverse osmosis tubular module. NTR-1510 (manufactured by Nitto Denko), RO-T2 reverse osmosis equipment
0, RO-HF55-1, RO-SW-1 (all manufactured by ULVAC SERVICE) and the like.

As described above, the fraction containing the proanthocyanidin-containing liquid with a molecular weight cutoff of 50
The conditions for treatment with an ultrafiltration membrane of 00 or less and / or a reverse osmosis membrane with a salt exclusion rate of 30% or less will be described.

First, when the ultrafiltration membrane is used, the temperature is 0 to 80.
° C., usually 5 to 50 ° C., pressure: normal 0.2~10kg / cm ² (gauge pressure), the average water permeation rate; when subjected to filtration at 5~100 / m ³ · hr or so, also the use of reverse osmosis membrane, Temperature; 0-80
Permeation treatment is carried out at a temperature of usually 50 to 50 ° C, a pressure of usually 20 to 100 kg / cm ² (gauge pressure), and an average water permeation rate of 30 to ²⁰⁰ / m ³ · hr.

In the present invention, both the above-mentioned ultrafiltration membrane and reverse osmosis membrane may be used, and in that case, it is desirable to carry out the ultrafiltration membrane treatment prior to the reverse osmosis membrane treatment.

After the above membrane treatment, the molecular weight cutoff is 500 to 5
Fraction 000 is collected to obtain highly pure proanthocyanidins.

The proanthocyanidin obtained by the above operation may be used as a product as it is, or may be powdered by a conventional method such as freeze-drying or spray-drying if necessary.

By the above operation, the desired high-purity proanthocyanidin can be obtained in a good yield by a simple operation.

〔The invention's effect〕

According to the present invention, a highly pure proanthocyanidin can be obtained in a simple operation with a high yield, and the present invention is extremely significant industrially.

Hereinafter, the present invention will be specifically described with reference to examples.

〔Example〕

Example 1 1 kg of inner bark of fresh cypress (scientific name, Chamaecyparis obtusa)
Triturate (dry matter equivalent) with 70% ethanol 10 in a Waring blender to obtain an aqueous ethanol extract 9
Got After washing it three times with petroleum ether 9,
Ethanol was removed by concentration under reduced pressure at ˜38 ° C., and then a water-containing ethanol solution having each alcohol concentration was added to obtain Proanthocyanidin-containing liquid 3.

This solution was filtered through an ultrafiltration membrane SEP-1013 (Asahi Kasei Co., Ltd., nominal molecular weight cutoff 3000), and the obtained filtrate was then reverse osmosis membrane DRS-10 (manufactured by Daicel Chemical Industries, salt rejection (10 ~ 20
%) To concentrate the membrane to obtain 300 ml of a concentrated solution.

This was freeze-dried, and a yellowish brown crude proanthocyanidin powder was obtained.

The analytical values of the obtained crude proanthocyanidins are shown in Table 1.

In Table 1, the amount of proanthocyanidin was determined by first dissolving 50 mg of the sample in 5 ml of water and washing 3 times with 5 ml of diethyl ether to remove flavanol monomers, and then removing all flavanols in the aqueous layer from RB Broadhurst. Et al. (J.Sci.Fd
Agric., 1978, 29, 788-794). As a standard product, the method of R. Eastmond (J. Inst Brew., 1974, vol.
80,188-192) dimeric procyanidin B-
A calibration curve was prepared using 3 and the quantitative value was calculated as a dimer procyanidin B-3 conversion value.

Example 2 1 kg (dry matter equivalent) of inner bark of fresh mackerel (Chamaecyparis pisifera) was ground and extracted with 70% ethanol 10 in a Waring blender to obtain an aqueous ethanol extract 9. This was washed 3 times with petroleum ether 9, concentrated under reduced pressure at 35 to 38 ° C. to remove ethanol, and then a 20% ethanol solution was added to obtain a proanthocyanidin-containing liquid 3.

This solution was filtered using an ultrafiltration membrane DM5 (manufactured by Amicon Far East Limited, nominal molecular weight cutoff 5000), and the resulting filtrate was then applied to an ultrafiltration membrane UM2 (nominal molecular weight cutoff 1000). And filtered to collect the filtrate 3.

This was freeze-dried, and the yellowish brown proanthocyanidin powder was 72.3 g (proanthocyanidin minor content 86.2%).
was gotten.

Example 3 Using 10 g of (±) -catechin and 10 g of (±) -taxifolin as raw materials, the method of R. Eastmond (J. Inst. Brew., 1974, vol. 8).
0,188-192) was used to synthesize procyanidin B-3, and the pH was adjusted (pH 5.0) using acetic acid.

Proanthocyanidin-containing liquid DRS-10 thus obtained
240 ml with (Daicel Chemical Co., Ltd., salt rejection rate 10-20%)
Concentrated to. 16.7% hydrous ethanol was added to this concentrated solution.
2.16 was added and the above reverse osmosis was performed again.
0 ml was obtained.

This was freeze-dried to obtain 4.3 g of a pale yellowish brown powder (content of procyanidin dimer: 83%). The molecular weight distribution of this product is determined by the method of AGH Lea et al. (J. Sci. Fd Agric., 1978, 29, 471).
-477) and separated by TLC, and analyzed with a high-speed thin-layer chromatography scanner (CS-920 type, manufactured by Shimadzu Corporation). At that time, as a standard product, a synthetic procyanidin B-3 prepared by the method of R. Eastmond was used.

Claims (4)

[Claims] 1. A proanthocyanidin-containing solution is treated with an ultrafiltration membrane having a molecular weight cutoff of 5000 or less and / or a salt exclusion rate of 30%.
After treatment with the following reverse osmosis membrane, the molecular weight cutoff is 500-5000.
A method for producing proanthocyanidins, which comprises collecting the fraction of 2. The process for producing proanthocyanidins according to claim 1, wherein the proanthocyanidin-containing liquid is a proanthocyanidin-containing liquid of 10 p.pm or more. 3. A solution containing a proanthocyanidin is 5 (V /
V) The method for producing proanthocyanidins according to claim (1), which is an alcohol-containing liquid having a concentration of at least%. 4. A proanthocyanidin-containing liquid is filtered through an ultrafiltration membrane having a molecular weight cutoff of 5000 or less, and the filtrate is concentrated by a reverse osmosis membrane having a salt rejection rate of 30% or less.
The method for producing proanthocyanidins according to item (1).