Separation medium, use for separation medium, steviol glycoside separation method using separation medium, and steviol glycoside production method using separation method

Abstract

An object of the present invention is to provide a separation medium and a separation method, ensuring high selectivity and good separation efficiency for specific steviol glycosides. The present invention is related to a separation medium in which polyethyleneimine is immobilized to porous particles of a (meth)acrylic polymer having a crosslinked structure and a hydroxyl group.

1 . A separation medium in which polyethyleneimine is immobilized to porous particles of a (meth)acrylic polymer having a crosslinked structure and a hydroxyl group. 
     
     
         2 . The separation medium according to  claim 1 , wherein a mass average molecular weight of the polyethyleneimine is 200 or more. 
     
     
         3 . The separation medium according to  claim 1 , wherein a nitrogen content rate is from 0.3 to 30% by mass. 
     
     
         4 . The separation medium according to  claim 1 , wherein a pore diameter of the porous particles is from 1 to 1,000 nm. 
     
     
         5 . A separation medium used for separation of a steviol glycoside, in which polyethyleneimine is immobilized to at least one porous particles selected from the group consisting of a (meth)acrylic polymer, a vinyl acetate polymer, polysaccharides, silica and glass. 
     
     
         6 . The separation medium according to  claim 5 , wherein the porous particles contain a (meth)acrylic polymer. 
     
     
         7 . The separation medium according to  claim 5 , wherein a nitrogen content rate is from 0.3 to 30% by mass. 
     
     
         8 . Use of the separation medium according to  claim 1  for separation of a steviol glycoside. 
     
     
         9 . A separation method for a steviol glycoside, comprising a liquid chromatography step of loading a solution containing two or more types of steviol glycosides to the separation medium according to  claim 1  and flowing a solvent A through the separation medium, thereby separating at least two types of steviol glycosides included in the steviol glycosides. 
     
     
         10 . The separation method for steviol glycosides according to  claim 9 , wherein the solution containing two or more types of steviol glycosides contain rebaudioside A and at least one fraction obtained in the liquid chromatography step is a fraction containing rebaudioside A as a main component. 
     
     
         11 . The separation method for steviol glycosides according to  claim 9 , wherein the solvent A contains alcohols freely miscible with water. 
     
     
         12 . The separation method for steviol glycosides according to  claim 9 , wherein in the liquid chromatography step, decolorization of a pigment component in the solution is performed at the same time. 
     
     
         13 . A separation method for a steviol glycoside, comprising an adsorption step of bringing a solution containing two or more types of steviol glycosides and a solvent B into contact with the separation medium according to  claim 1  to adsorb the steviol glycosides to the separation medium, and an elution step of eluting the steviol glycosides from the separation medium by using a solvent C, thereby obtaining two or more fractions containing different steviol glycosides as a main component, respectively. 
     
     
         14 . The separation method for a steviol glycoside according to  claim 13 , wherein the solution containing two or more types of steviol glycosides contains rebaudioside A and at least one fraction obtained in the elution step is a fraction containing rebaudioside A as a main component. 
     
     
         15 . The separation method for steviol glycosides according to  claim 13 , wherein the solvent B and the solvent C contain alcohols freely miscible with water. 
     
     
         16 . The separation method for steviol glycosides according to  claim 13 , wherein the solvent C is higher in polarity than the solvent B. 
     
     
         17 . The separation method for steviol glycosides according to  claim 13 , wherein the solvent B is propyl alcohol, ethyl alcohol or methyl alcohol. 
     
     
         18 . The separation method for steviol glycosides according to  claim 13 , wherein in the elution step, decolorization of a pigment component in the solution is performed at the same time. 
     
     
         19 . A production method for steviol glycosides, comprising a step of separating at least two types of steviol glycosides from a solution containing two or more types of steviol glycosides by the separation method for a steviol glycoside according to  claim 9 .