JPH02145658A - Purification of carthamin - Google Patents

Abstract

PURPOSE:To obtain carthamin (a red pigment) having high purity by treating a carthamin-containing raw material with an alkaline aqueous solution, contacting with a porous polymer resin after pH adjustment to effect the adsorp tion of the pigment, washing the resin with water, etc., and treating with a water-containing organic solvent. CONSTITUTION:A carthamin-containing raw material (e.g., safflower) is treated with an alkaline aqueous solution and the obtained extracted liquid is adjusted to pH5-9. The solution is made to contact with a porous polymer resin and the resin containing adsorbed pigment is washed with water and/or hydrated alcohols having a water-content of >=70% and then treated with a hydrated organic solvent (e.g., methanol or acetone) having a water-content of <=50% to elute the adsorbed carthamin.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for purifying carsamine to obtain highly purified carsamine from a carsamine-containing raw material such as safflower. More specifically, the present invention relates to a method for isolating and purifying cursamine from a pigment component of a cursamine-containing raw material.

(Prior Art) Red safflower pigment (cursamine) has been used as a traditional craft for dyeing textiles and the like since ancient times. The method involves eluting cursamine with alkaline water, adding vinegar to it, and dyeing the fibers with the acidic solution.

As an improvement on this traditional method, for example, a method of separating cursamine from safflower using a water-containing organic solvent (
(Japanese Patent Publication No. 30-8943), a method of extracting carthamine from safflower with a water-containing organic solvent, precipitating the carthamine at -10°C after removing the solvent, and separating the carthamine with a mixed solvent of tetrahydrofuran, benzene, and water (a method of separating the carthamine with a mixed solvent of tetrahydrofuran, benzene, and water). Kosho 47
-50762) has been proposed. These methods had the disadvantage that impurities were also extracted and separation of these impurities was difficult.

Furthermore, a method in which an alkaline solution in which carthamine is extracted from safflower is insolubilized using an acid, adsorbed onto chitosan and/or cellulose, and extracted with alkali and an organic solvent to obtain carthamine (Japanese Unexamined Patent Publication No. 117069/1982); A method has been proposed in which purified cursamine is obtained by adding silica gel to an alkaline solution in which cursamine is extracted from safflower to adsorb cursamine, making it insolubilized with acid, and then extracting with hydrous acetone (Japanese Patent Laid-Open Publication No. 53375/1983).

- (Problem to be solved by the invention) However, adsorbents such as chitosan and/or cellulose and silica gel as described above have low adsorption selectivity for casamine, and in order to remove safflower yellow and other impurities, it is necessary to adjust the pH to 2. The process was extremely complicated, as it was necessary to insolubilize the cursamine by lowering the concentration to .about.3, dry the adsorbent adsorbing the cursamine, and then extract it with a water-soluble organic solvent. Moreover, these methods were still insufficient to obtain cursamine with high purity.

An object of the present invention is to solve the above-mentioned conventional drawbacks and to provide a new method for obtaining a highly purified carthamine with a clear color tone in a simple manner and industrially advantageous.

(Means for Solving the Problems) According to the present invention, a carsamine-containing raw material is treated with an alkaline aqueous solution, the resulting extract is adjusted to pH 8 to 9, and then brought into contact with a porous polymer resin to adsorb the pigment. A method for purifying carthamine, which comprises washing the resin with water and/or a hydrous alcohol having a water content of 70% or more, and then treating it with a water-containing organic solvent having a water content of 50% or less to elute the carthamine. provided.

It is already known that water-soluble anthocyanin pigments such as grape skin pigment and hibiscus pigment can be collected by treating them with a porous resin adsorbent (Japanese Patent Laid-Open No. 48-661
No. 28, Japanese Patent Publication No. 59-50262). However, the water-insoluble carthamine, which is the red pigment of safflower, is brought into contact with a porous polymer resin under slightly alkaline conditions to adsorb the carthamine, and after removing the water-soluble pigment by washing with water, it is eluted with a water-containing organic solvent to collect the carthamine. is not known.

Examples of the cursamine-containing raw material used in the present invention include safflower, dried safflower, and warp kasuri.

These raw materials may be shredded into appropriate sizes as desired. Carsamine-containing raw materials are washed with water in a conventional manner to remove part of the yellow pigment in advance, and then treated with an alkaline aqueous solution to extract carsamine.

Examples of the alkaline aqueous solution include about 0.1 to 10% by weight, preferably about 0.1 to 10% by weight, of alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, or alkali metal carbonates such as sodium carbonate and potassium carbonate. 0.5-5.
An aqueous solution of about 0% by weight is used.

The amount of alkaline aqueous solution used is, for example, 1 dry safflower petal.
Examples include amounts such as about 10 to 20 parts by weight.

In the method for extracting cursamine, a cursamine-containing raw material is added to an alkaline aqueous solution and stirred at about 0 to 30°C for about 10 minutes to 2 hours. After the extraction process, solid-liquid separation is performed by filtration, centrifugation, etc., and the extract is collected.

The pH of the Cursamine extract is adjusted to 8 to 9 using an acid.

Examples of acids used for pH adjustment include inorganic acids such as hydrochloric acid, phosphoric acid, and carbonic acid; and organic acids such as acetic acid, citric acid, malic acid, and tartaric acid.

The pH-adjusted extract is then treated with a porous polymeric resin to adsorb cursamine. Examples of the porous polymer resin include styrene-divinylbenzene copolymer, methacrylic acid ester polymer, crosslinked polystyrene, acrylonitrile-divinylbenzene copolymer, and the like.

All of these porous polymer resins are commercially available, for example, Diaion (HPIo, 20, 30.40.5
0; 5P-207, 5P-206 manufactured by Mitsubishi Chemical Industries);
Amberly L- (XAD-2゜XAD-4: manufactured by Rohm and Haas): Chromosorp Fist Centiury Chr
omosorb century 101~108 (
Johns Manville, Inc.).

The adsorption treatment method for porous polymeric resin is carried out by bringing the extract into contact with the porous polymeric resin, but preferably, for example, by passing the extract through a column filled with porous polymeric resin, the adsorption treatment is carried out by force. Samin is adsorbed onto the porous polymeric resin.

The amount of porous polymer resin used in the extract solution varies depending on the concentration of cursamine in the extract solution.
About 0.04 to 1 part by weight of the resin is used. The porous polymer resin filled in the column is moistened by flowing water in advance, and the cursamine extract is, for example, Sv about 0.
．． This is done by passing the liquid at a flow rate of 5-5. After the adsorption treatment, the column is heated with water and/or with a water content of about 70-9
Washing with water-containing methanol or water-containing ethanol having a water content of 5% by weight, preferably about 70-80% by weight, removes safflower yellow and other impurities.

Next, the cursamine adsorbed on these resins is eluted using a water-containing organic solvent. Examples of such water-containing organic solvents include water-miscible organic solvents such as methanol, ethanol, and acetone having a water content of about 50% by weight or less. In the elution process, these organic solvents are used, for example, at sv about 0
．． Run through the column at a flow rate of 5-5.

By removing the solvent from the resulting eluate, extremely pure casamine can be obtained in high yield.

Next, embodiments of the present invention will be explained in more detail with reference to Examples.

(Example) Example 1 100 g of dried safflower petals was washed with 200 mQ of water to remove yellow pigment. Next, 1.200 g of a 4% sodium carbonate solution was added to the washed safflower petals to extract cursamine. After adjusting the pH to 8.5 by adding 6N hydrochloric acid to the obtained carthamine extract, the liquid was passed through a column packed with 150 mff of porous polymer resin 5P-20 (Mitsubishi Kasei) at a Sv of about 1 to adsorb carthamine. Then, 300 mf of water
Wash sequentially with 300 g of 20% methanol and
Remaining salts and yellow pigment were removed. Next, 600 rx (2) of 80% methanol was flowed to desorb carthamine, and methanol was removed from the resulting solution by vacuum distillation to obtain 150 mg of highly pure carthamine.

Example 2 500 g of safflower petals were crushed and washed with 10Q of water to remove yellow pigment. 1.500 g of a 4% potassium carbonate aqueous solution was added to the washed safflower petals and stirred to extract cursamine. The pH of the obtained extract was adjusted to 8 and 8 in the same manner as in Example 1.
After adjusting to 5, porous polymer resin HP-20 (Mitsubishi Kasei) 2
SVI was passed through a column filled with 00mQ to adsorb cursamine.

The resin adsorbed with Carsamine was washed with 400 mQ of water and 400 mQ of 25% ethanol, respectively, to remove impurities such as remaining salts and yellow pigment.

Carsamine was then desorbed using 800rnQ of 95% ethanol, and ethanol was removed by vacuum distillation to obtain 230 mg of highly pure carsamine.

(Effects of the Invention) According to the method of the present invention, by using a porous polymer resin with excellent adsorption selectivity for carthamine, carthamine in an alkaline extract of safflower adsorbed to the resin can be adjusted to pH 2 to 3. pH without lowering and insolubilization treatment
It became possible to wash with water under slightly alkaline conditions of 8 to 9.

As a result, it is possible to eliminate impurities other than cursamine, which were conventionally included when insolubilizing cursamine, and it is possible to easily remove impurities such as safflower yellow by washing with water under the slightly alkaline conditions described above12, making a dramatic leap forward. Carsamine of high purity and high quality can be obtained industrially with great advantage.

Patent applicant: Hasegawa Fragrance Co., Ltd. Representative Patent Attorney Masaaki Kobayashi

Claims (1)

[Claims] After treating the Carsamine-containing raw material with an alkaline aqueous solution and adjusting the pH of the obtained extract to 8 to 9, it is brought into contact with a porous polymer resin to adsorb the dye, and the resin is mixed with water and/or with a water content of 70% or more. A method for purifying carthamine, which comprises washing with a water-containing alcohol and then treating with a water-containing organic solvent having a water content of 50% or less to elute the carthamine.