title: Conversion of cyclodextrin into high-amylose starch of low molecular mass by means of cyclodextrin glucanotransferase.
abstract: alpha-Cyclodextrin (CD) was converted by Bacillus macerans cyclodextrin glucanotransferase into highly insoluble high-amylose starch with a low average degree of polymerization (56-73), in yields as high as 78% over a wide range of temperatures (25-70 degreesC). Ability to undergo this conversion was highly concentration-dependent. gamma-CD was also convertible in good yield; however, beta-CD was relatively resistant to conversion. Degrees of polymerization and the percentages of amylose in the high-amylose products were estimated from spectrophotometric measurements on their iodine complexes. A plausible mechanism for conversion of CD into starch is proposed.
authors.affiliation: Biopolymer Research Unit, National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Agricultural Research Service, 1815 N. University St., Peoria, IL 61604, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Rendleman
authors.forename: C A
authors.initials: CA
authors.lastname: Knutson
mesh_terms: D000688:Amylose / Q000032:analysis*; D003505:Cyclodextrins / Q000737:chemistry*; D005964:Glucosyltransferases / Q000737:chemistry*; D008970:Molecular Weight; D011134:Polysaccharides / Q000737:chemistry; D013213:Starch / Q000737:chemistry*; D013379:Substrate Specificity; D013696:Temperature; D047391:alpha-Cyclodextrins
chemical_list: D003505:Cyclodextrins; D011134:Polysaccharides; D047391:alpha-Cyclodextrins; D013213:Starch; D000688:Amylose; D005964:Glucosyltransferases; C019963:cyclomaltodextrin glucanotransferase; C032613:alpha-cyclodextrin