JPS61178953A - Method for purifying tyrosine - Google Patents

Abstract

PURPOSE:To purify tyrosine by simple procedures, by bringing a tyrosine solution containing phenylalanine as a main impurity into contact with a nonpolar porous synthetic adsorbent. CONSTITUTION:A tyrosine solution containing phenylalanine as a main impurity is brought into contact with a nonpolar porous synthetic intermediate, e.g. HP 10, HP 20 or SP 207 (manufactured by Mitsubishi Chemical Industries Ltd.) or XFS-4022 (manufactured by Dow Chemical Co.) to adsorb the phenylalanine thereon and give the purified tyrosine containing no phenylalanine or with remarkably reduced concentration thereof. The above-mentioned method is preferably carried out by the column method.

Description

Detailed Description of the Invention The present invention involves treating a tyrosine solution containing phenylalanine as a main contaminant with a non-polar porous synthetic adsorbent to obtain tyrosine that does not contain phenylalanine or has a significantly reduced concentration. It's about how to do it.

Obtaining tyrosine from protein hydrolysis solutions and fermentation solutions has already been carried out industrially. In many cases, tyrosine obtained by these methods contains phenylalanine as a contaminant, and it is difficult to separate it from phenylalanine using conventional purification methods such as recrystallization and ion exchange resin methods. Kosho 33-3789).

An object of the present invention is to provide a method for obtaining tyrosine that does not contain phenylalanine or has a significantly reduced concentration by a simple operation from a tyrosine solution containing phenylalanine as a main impurity.

The present inventor has discovered that by contacting a tyrosine solution contaminated with phenylalanine etc. with a non-polar porous synthetic adsorbent based on polystyrene divinylbenzene, and adsorbing only phenylalanine to the resin, a high purity L-tyrosine solution is used. It has been found that it can be easily obtained.

In the present invention, phenylalanine and tyrosine may be optically active or racemic.

The tyrosine solution referred to in the present invention refers to tyrosine fermentation liquid, protein hydrolysis liquid, intermediate process liquid for recovering cytyrosine from such fermentation liquid and hydrolysis liquid, and crude tyrosine containing phenylalanine obtained from these. crystal solution,
Other impurities include a tyrosine solution containing at least phenylalanine.

The concentration of tyrosine may be any value as long as it is below the solubility, but it is advantageous to dissolve it in acidic or alkaline liquids to increase the solubility. However, since the amount of phenylalanine adsorbed to the adsorbent increases in alkaline conditions than in acidic conditions, dissolving phenylalanine in an alkaline solution is more advantageous in purifying tyrosine. Furthermore, the salt in the solution (N*
Since the amount of phenylalanine adsorbed to the adsorbent increases as the concentration (C1,N&2So4゜NH2Cl, etc.) increases, these salts may be added to the tyrosine solution and then brought into contact with the adsorbent. The phenylalanine concentration is not particularly limited.

The non-polar porous synthetic adsorbents referred to in the present invention include, for example, Diaion HP 10.1 (P2O, 5P207 (Mitsubishi Chemical Corporation fA), XAD-2, XAD-4, XAD-20
00 (manufactured by Amu & Haas), XFS-4022
(manufactured by Dow Chemical Company), but it is not limited to these, and any other non-polar porous synthetic adsorbent that has similar properties as these can be used. Good too.

As a method of contacting Prozin solution and adsorbent,
Although there is a column method, it is preferable to use the column method.

For example, when a column is filled with a non-polar porous synthetic adsorbent and a tyrosine solution containing phenylalanine as a contaminant is passed from the top of the column, phenylalanine has a greater adsorption force on the adsorbent, so phenylalanine reaches saturation adsorption. Until this point, phenylalanine is preferentially adsorbed, and a tyrosine solution containing no phenylalanine can be obtained as a flowthrough.

A tyrosine solution is passed through a column containing a porous synthetic adsorbent, and when the concentration of phenylalanine in the tyrosine solution flowing out from the adsorbent exceeds an allowable amount, the flow is stopped and the adsorbent is regenerated. Regeneration is carried out in a conventional manner, first by extruding the tyrosine solution in the adsorbent bed with water and recovering it. Phenylalanine adsorbed on the adsorbent can be easily eluted with, for example, an aqueous solution of water, an alkali, an acid, a lower aliphatic alcohol such as methanol, emenol, inglobil alcohol, an acetone aqueous solution, or a mixed solution thereof. After the regeneration is completed, the adsorbent is washed with water and the tyrosine solution is passed through it again.

Example I L-tyrosine solution containing L-tyrosine (concentration 2.4%) and L-phenylalanine (concentration 0.15%) (adjusted to −=1.0 with sodium hydroxide) 75Qsu was purified using a column method. Polar porous synthetic adsorbent 5P207 (manufactured by Mitsubishi Chemical Corporation)
I QQd (height 50α, diameter 1.6αO color A)
By passing the solution through K 5V=1.0 and collecting both portions from 70d to 700d, 630ju of L-prosine solution containing no L-phenylalanine (L-tyrosine concentration 2.0d) was obtained.
37chi) was obtained.

This solution was neutralized and crystallized using hydrochloric acid in a conventional manner to obtain L-tyrosine crystal 14.0.9 containing no L-phenylalanine. T, L, C, (thin layer chromatography) monos?, t.

Example 2 L-tyrosine solution containing L-tyrosine (concentration 2.4%) and L-phenylalanine (concentration 0.15%) (using hydrochloric acid - = 1.0KvI4) 60 (Ml-force formula) Non-polar porous synthetic adsorbent 5P207 (Mitsubishi Kasei Corporation i)
) 100m/(height 50α, diameter 1.6α column) at 5V=1.0 and collect the fractions from 180Wj to 560x/ to obtain L-tyrosine that does not contain any L-2 enylalanine. Solution 380d (L-tyrosine concentration 2.
4%).

This solution was neutralized and crystallized using sodium hydroxide in a conventional manner to obtain 8.8 g of L-tyrosine crystals.

Example 3 350 d of an L-tyrosine solution (adjusted to -=11.5 using sodium hydroxide) containing L-tyrosine (concentration 5.0%) and L-phenylalanine (concentration 1.5%) was prepared in a column manner. , non-polar porous synthetic adsorbent XAD-2000
'(Roat A 77t/% - made by S.A.) 100ju (
Height 50cm5! 5v=i, for a column with a diameter of 1.6α).

A solution of I,-tyrosine 239d (4.9% L-tyrosine) containing no L-phenylalanine was obtained by collecting fractions from 701Lt to 3001Lt.

This solution was neutralized and crystallized using rosacean acid in a conventional manner to obtain L-tyrosine crystals 10.9.9.

Example 4 Monotyrosine solution (adjusted to -11.0 with sodium hydroxide v4) containing L-tyrosine (concentration 0.5%) and L-phenylalanine (concentration 4.5%) 3001/ in a column system, Non-polar porous synthetic adsorbent XFS-4022 (manufactured by Dow Chemical Company)
crpt (D column) ic 5V=2.0 was passed through the column, and fractions 7Qd to 270117 were collected to obtain L-tyrosine solution 200d. This solution contains 0.00 L-tyrosine.
67%.

It contained 0010% of L-2 engineered nylalanine.

As understood from this example, phenylalanine has a much greater adhesion force to the non-polar porous synthetic adsorbent than tyrosine.

Claims (1)

[Claims] A method for purifying tyrosine, which comprises contacting a tyrosine solution containing phenylalanine as a main impurity with a non-polar porous synthetic adsorbent to adsorb phenylalanine.