title: Production of isocyclomaltopentaose from starch using isocyclomaltooligosaccharide glucanotransferase.
abstract: Production of a novel cyclomaltopentaose cyclized by an alpha-1,6-linkage, [ICG5; cyclo-{-->6)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->}], from starch was performed using isocyclomaltooligosaccharide glucanotransferase (IGTase) derived from Bacillus circulans AM7. The optimal conditions for ICG5-production from partially hydrolyzed starch were as follows: substrate concentration, 1.0% (w/v); pH, 5.5; temperature, 45 degrees C; reaction time, 24 h, IGTase, 1.0 unit/g-dry solid (DS); isoamylase, 2,500 units/g-DS. The yield of ICG5 reached 25.9% under optimal conditions. ICG5-production was achieved from partially hydrolyzed starch using a crude enzyme preparation containing IGTase. Finally, ICG5 was obtained in a yield of 17.9% (99.3% purity, 2,681 g-DS). A digestive test with a human salivary amylase, an artificial gastric juice, a pancreatic amylase, and small intestinal enzymes showed that ICG5 was an indigestible oligosaccharide.
authors.affiliation: Glycoscience Institute, Research Center, Hayashibara Biochemical Laboratories, Inc. h-watanabe@hayashibara.co.jp
authors.forename: Hikaru
authors.initials: H
authors.lastname: Watanabe
authors.forename: Rohko
authors.initials: R
authors.lastname: Takakura-Yamamoto
authors.forename: Mayumi
authors.initials: M
authors.lastname: Kurose
authors.forename: Kenshi
authors.initials: K
authors.lastname: Yoshida
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Oku
authors.forename: Ikuo
authors.initials: I
authors.lastname: Sawatani
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Nishimoto
authors.forename: Michio
authors.initials: M
authors.lastname: Kubota
authors.forename: Hiroto
authors.initials: H
authors.lastname: Chaen
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Fukuda
mesh_terms: D001407:Bacillus / Q000201:enzymology; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D005964:Glucosyltransferases / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007517:Isoamylase / Q000378:metabolism; D007700:Kinetics; D009844:Oligosaccharides / Q000138:chemical synthesis*; D013213:Starch / Q000737:chemistry*; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D009844:Oligosaccharides; C514763:cyclo(-6-glucopyranosyl-1-4-glucopyranosyl-1-4-glucopyranosyl-1-4-glucopyranosyl-1-4-glucopyranosyl-1); D013213:Starch; D005964:Glucosyltransferases; C514764:isocyclomaltooligosaccharide glucanotransferase, Bacillus circulans; D007517:Isoamylase