Process for producing aglycon and flavor-improved food containing the aglycon by diglycosidase, and converting agent to be used in the process

Abstract

A physiologically active substance of aglycon type, in particular, aglycon isoflavone, can be efficiently produced, without resort to any acid/alkali treatment or fermentation and substantially without changing the physical properties of a material, by treating the material with a sufficient amount of diglycosidase for a sufficient period of time at an appropriate temperature and pH so that a physiologically active substance of glycoside type contained in the material can be converted into the physiologically active substance of aglycon type. Moreover, by using diglycosidase and/or a specific enzyme preparation, the aglycon content in a protein or protein-containing food can be increased and the flavor thereof can be improved.

1 . A process for producing a protein having an increased aglycon content or a food containing the protein, which comprises a step of treating a protein or protein-containing food with diglycosidase, wherein said diglycosidase has activity to act upon a disaccharide glycoside to release saccharides in a disaccharide unit.  
   
   
       2 . The process for producing a protein having an increased aglycon content or a food containing the protein according to  claim 1 , wherein the protein or protein-containing food contains a glycoside containing an isoflavone as the aglycon.  
   
   
       3 . The process for producing a protein having an increased aglycon content or a food containing the protein according to  claim 1  or  2 , wherein the protein or protein-containing food to be produced is a further flavor-improved one.  
   
   
       4 . The process for producing a protein having an increased aglycon content or a food containing the protein according to  claim 1  or  2 , wherein the glycoside containing an isoflavone as the aglycon is one or more selected from the group consisting of daidzin, genistin, or glycitin and acetyl derivatives, succinyl derivatives, or malonyl derivatives thereof.  
   
   
       5 . The process for producing a protein having an increased aglycon content or a food containing the protein according to  claim 1  or  2 , which further comprises a step of treating with an enzyme preparation containing mainly at least one enzyme selected from the group consisting of amylases, proteases, lipases, β-glucosidases, and yeast-dissolving enzymes.  
   
   
       6 . The process for producing a protein having an increased aglycon content or a food containing the protein according to  claim 1  or  2 , wherein the improvement of flavor is reduction of bitterness and/or astringency.  
   
   
       7 . A process for producing a flavor-improved protein or a food containing the protein, which comprises a step of treating a protein or protein containing food with a diglycosidase and an enzyme preparation containing mainly at least one enzyme selected from the group consisting of amylases, cellulases, pectinases, proteases, lipases, β-glucosidases, β-galactosidases, and yeast-dissolving enzymes, wherein said diglycosidase has activity to act upon a disaccharide glycoside to release an aglycon and saccharides in a disaccharide unit.  
   
   
       8 . The process for producing a flavor-improved protein or a food containing the protein according to  claim 7 , wherein the protein or protein-containing food contains a glycoside containing a flavonoid as the aglycon.  
   
   
       9 . The process for producing a flavor-improved protein or a food containing the protein according to  claim 7  or  8 , wherein the protein or protein-containing food contains a glycoside containing an isoflavone as the aglycon.  
   
   
       10 . A method of administering diglycosidase orally to form an aglycon from a glycoside in a living body, wherein said diglycosidase has activity to act upon a disaccharide glycoside to release saccharides in a disaccharide unit.  
   
   
       11 . The method according to  claim 10 , wherein diglycosidase is orally administered to form an aglycon in a living body from a glycoside containing an isoflavone as the aglycon.  
   
   
       12 . A method of accelerating a bioabsorption of a physiologically active substance, which comprises administering diglycosidase orally before, during, or after the ingestion of a food containing a physiologically active substance of glycoside type, wherein said diglycosidase has activity to act upon a disaccharide glycoside to release saccharides in a disaccharide unit.  
   
   
       13 . An agent for converting a physiologically active substance of glycoside type into the physiologically active substance of aglycon type, which contains at least a diglycosidase, wherein said diglycosidase has activity to act upon a disaccharide glycoside to release saccharides in a disaccharide unit.