Process for producing cyclodextrins

Claim 2

A process for the production and recovery of cyclodextrins which consists of the steps of: (a) reacting gelatinized or liquefied starch with cyclodextrin glycosyltransferase to prepare a mixture containing cyclodextrins and acyclic dextrins; (b) reacting said mixture from step (a) with a saccharogenic enzyme capable of hydrolyzing said acyclic dextrins and having substantially no hydrolytic action on said cyclodextrins, to convert said acyclic dextrins into reducing sugars, whereby a sugar solution containing cyclodextrins and reducing sugars as primary components is obtained; (c) passing said sugar solution from step (b) through a column packed with an alkali or an alkaline earth metal salt of a strongly acidic cation exchange resin; and (d) eluting the cyclodextrins from the column with water to recover them.

Claim 3

The process according to claim 1, wherein said saccharogenic enzyme is selected from the group consisting of glucoamylase, β-amylase, a mixture of α-1,6-glucosidase with glucoamylase, and a mixture of α-1,6-glucosidase with β-amylase.

Claim 4

The process according to claim 1, wherein said strongly acidic cation exchange resin is a cross-linked styrene-divinylbenzene copolymer having sulfonyl groups.

Claim 5

A process for the production and recovery of α-cyclodextrin which consists of the steps of: (a) reacting gelatinized or liquefied starch with cyclodextrin glycosyltransferase to prepare a mixture containing α, β and γ-cyclodextrins and acyclic dextrins; (b) reacting the mixture from step (a) with a saccharogenic enzyme capable of hydrolyzing said acyclic dextrins, γ-cyclodextrin and β-cyclodextrin, said enzyme having substantially no hydrolytic action on α-cyclodextrin, whereby said γ-cyclodextrin and β-cyclodextrin and said acyclic dextrins are converted into reducing sugars, and a sugar solution is obtained containing α-cyclodextrin and reducing sugars as primary ingredients; (c) passing the sugar solution from step (b) through a column packed with an alkali or an alkaline earth metal salt of a strongly acidic cation exchange resin; and (d) eluting α-cyclodextrin with water from the column to recover it.

Claim 6

A process for the production and recovery of α-cyclodextrin which consists of the steps of: (a) reacting gelatinized or liquefied starch with cyclodextrin glycosyltransferase to prepare a mixture containing α, β and γ-cyclodextrins and acyclic dextrins; (b) reacting the mixture from step (a) with a saccharogenic enzyme capable of hydrolyzing said acyclic dextrins, γ-cyclodextrin and β-cyclodextrin, said enzyme having substantially no hydrolytic action on α-cyclodextrin, whereby said γ-cyclodextrin and β-cyclodextrin and said acyclic dextrins are converted into reducing sugars, and a sugar solution is obtained containing α-cyclodextrin and reducing sugars as primary ingredients; (c) passing the sugar solution from step (b) through a column packed with an alkali or an alkaline earth metal salt of a strongly acidic cation exchange resin; and (d) eluting α-cyclodextrin with water from the column to recover it.

Claim 7

The process according to claim 4, wherein said saccharogenic enzyme is selected from the group consisting of bacterial saccharogenic α-amylase, fungal α-amylase, a mixture of bacterial saccharogenic α-amylase with glucoamylase, and a mixture of fungal α-amylase with glucoamylase.

Claim 8

The process according to claim 4, wherein said strongly acidic cation exchange resin is a cross-linked styrene-divinylbenzene copolymer having sulfonyl groups.

Claim 9

The process according to claim 1, wherein the particle size of the resin is 20-200 mesh and said step (c) is carried out at a temperature of 50°-80° C., and pH of 3-6.

Claim 10

The process according to claim 4, wherein the particle size of the resin is 20-200 mesh and said step (c) is carried out at a temperature of 50°-80° C., and pH of 3-6.