The Initial Research Of β-cyclodextrin Glycosyltransferase And The Strain Producing The Enzyme

Cyclodextrin (CD) is a kind of ring oligose.It is connected by α -1,4 glucoside linkage with D- glucopyranose. With the different number of glucose molecular there are α,β,γ- cyclodextrin in the CD mixture. They have different properties because of their different structures. The hollow cylinder radius of the β-CD is just right so the β-CD has the same safety as the starch and the cyclodextrin. Because of its good functions, its development and application become to be the focuse.Due to the unordinary structure of β-CD, it builds a molecular gelatine capsules which can conceal a guest-molecular. Thus it has been widely applied in chemical, food and medical industries etc.β -cyclodextrin glycosyltransferases (β -CGTase) are starch-degrading enzymes which mainly convert starch and related substrates into cyclodextrins. According to researches, many kinds of bacteria can produce β -CGTase. When β-CGTase and starch produce β-CD high tempreture and high alkalinity are essential. So many kinds of β -CGTases which have the properties have not economic value. It is one of the important causes that leads to be restricted on the application of β-CD.So the goal of the study is screening the thermophilic and alkalophilic strain to increase the production of β-CD.