Crystal of reduced glutathione

Patent metadata

Field	Value
Publication number	US-10640532-B2
Application number	US-201615563581-A
Country	US
Kind code	B2
Filing date	Mar 31, 2016
Priority date	Mar 31, 2015
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

The present invention provides a crystal of reduced glutathione that is stable, and is easy to process, and a method for producing the crystal. According to the present invention, a crystal of a metal salt of reduced glutathione is produced by suspending an amorphous solid of a metal salt of reduced glutathione in a hydrophobic organic solvent, and adding water to the resulting suspension to precipitate a crystal of a metal salt of reduced glutathione.

First claim

The invention claimed is:

1. A crystal of a metal salt of reduced glutathione, which is a monohydrate crystal of a salt of reduced glutathione and sodium, and has peaks at a diffraction angle (2θ) of 19.90°±0.20°, 25.58°±0.20°, and 26.88°±0.20° in powder X-ray diffraction.

2. The crystal according to claim 1 , which has peaks also at a diffraction angle (2θ) of 20.16°±0.20°, 24.68°±0.20°, 26.30°±0.20°, 27.68°±0.20°, and 33.20±0.20° in powder X-ray diffraction.

3. The crystal according to claim 2 , which has peaks also at a diffraction angle (2θ) of 17.90°±0.20°, 20.86°±0.20°, 22.10°±0.20°, and 25.30°±0.20° in powder X-ray diffraction.

4. The crystal according to claim 3 , which has peaks also at a diffraction angle (2θ) of 6.42±0.20°, 18.90±0.20°, and 29.30±0.20° in powder X-ray diffraction.

5. A crystal of a metal salt of reduced glutathione, which is a monohydrate crystal of a salt of reduced glutathione and sodium, and has the following brief unit cell parameters: a=27.881 Å, b=10.818 Å, c=4.881 Å, α=90°, β=90°, γ=90°, V=1472.2 Å 3 , and Z=4 with a space group P2 1 2 1 2 1 (#19), as measured by single-crystal X-ray structure analysis at −173° C.

6. A method for producing a crystal of a metal salt of reduced glutathione, the method comprising dissolving a free form of reduced glutathione in a metal hydroxide aqueous solution, and adjusting the pH of the solution to 5.0 to 8.0 to obtain an aqueous solution of a metal salt of reduced glutathione; concentrating the resulting aqueous solution, and gradually adding a C1 to C6 alcohol to the concentrated aqueous solution in small portions in an amount 0.1 to 3 times the amount of the concentrated aqueous solution; and adding a crystal of a metal salt of reduced glutathione as a seed crystal to precipitate a crystal of a metal salt of reduced glutathione.

7. The method for producing a crystal of a metal salt of reduced glutathione according to claim 6 , wherein the C1 to C6 alcohol is methanol or ethanol.

8. The method for producing a crystal of a metal salt of reduced glutathione according to claim 6 , wherein the crystal of a metal salt of reduced glutathione is a monohydrate crystal of a salt of reduced glutathione and a metal selected from the group consisting of sodium, potassium, calcium, and magnesium.

9. The method for producing a crystal of a metal salt of reduced glutathione according to claim 6 , wherein the crystal of a metal salt of reduced glutathione is a monohydrate crystal of a reduced glutathione-sodium salt.

Assignees

• Univ Osaka Public Corp
• Kyowa Hakko Bio Co Ltd

Inventors

• Ooshima Hiroshi
• Igarashi Koichi
• Nagano Hiroshi
• Fujimoto Akihiro
• Fukumoto Kenta
• Fukumoto Kazunari
• Yokoi Tomoya

Classifications

• B01D9/0036

  Crystallisation on to a bed of product crystals; Seeding · CPC title

• B01D2009/009

  Separation of organic compounds by selective or extractive crystallisation with the aid of auxiliary substances forming complex or molecular compounds, e.g. with ureum, thioureum or metal salts · CPC title

• B01D9/04

  concentrating solutions by removing frozen solvent therefrom · CPC title

• B01D9/0054

  Use of anti-solvent · CPC title

• B01D9/005

  Selection of auxiliary, e.g. for control of crystallisation nuclei, of crystal growth, of adherence to walls; Arrangements for introduction thereof · CPC title