Cyclodextrins Properties and Applications

Enzymes for the production of cyclodextrins (CD) are produced by various bacteria (Table 22.1). No fungi or other organisms have been reported to produce CDTGase. Enzymes obtained from these bacteria differ in the relative amounts of a-, (3- and -cyclodextrins produced. Typically, a mixture of two or three cyclodextrins 

Starch Chemistry and Technology, Third Edition ISBN 978-0-12-746275-2 

In the transglycosylation reaction, a cyclodextrin or starch chain is cleaved and another starch chain is added to the cleaved chain, resulting in one longer linear chain and one shorter linear chain of glucopyranosyl units. This allows for the formation of a mixture of cydodextrins from a single reaction. 

CDTGase displays a-amylase activity. In this case, water is the acceptor and starch or the cyclodextrin is cleaved, resulting in a shorter starch chain or a linear malto-oligosaccharide when a cyclodextrin is the substrate. 

By using water-soluble organic solvents, usually referred to as precipitants, the reaction can be directed to produce only one cyclodextrin. In the presence of toluene, the enzyme from B. macerans produces only (3-cyclodextrin and linear starch chains. Beta-cyclodextrin can be separated from the soluble starch chains and recovered as a precipitated toluene complex. In the presence of decanol, a-cyclodextrin is the only cyclodextrin produced using the enzyme from B. macerans.21,22 Precipitants such as large cyclic compounds similar to musk oil23 or a-naphthol and methyl ethyl ketone (butanone)24 can be used to produce 8-cyclodextrin. 

---

S. Munoz-Botella, B. Del Castillo, M.A.Martyn, Cyclodextrin properties and applications of inclusion complex formation, Ars. Pharm., 36,187-98,1995. 

---