Synthesis of novel heterobranched beta-cyclodextrins from alpha-D-mannosylmaltotriose and beta-cyclodextrin by the reverse action of pullulanase, and isolation and characterization of the products.
Alpha-D-mannosyl-maltotriose (Man-G3) were synthesized from methyl alpha-mannoside and maltotriose by the transfer action of alpha-mannosidase. (Man-G3)-betaCD and (Man-G3)2-betaCD were produced in about 20% and 4% yield, respectively when Aerobacter aerogenes pullulanase (160 units per 1 g of Man-G3) was incubated with the mixture of 1.6 M Man-G3 and 0.16 M betaCD at 50 degrees C for 4 days. The reaction products, (Man-G3)-betaCD were separated to three peaks by HPLC analysis on a YMC-PACK A-323-3 column and (Man-G3)2-betaCD were separated to several peaks by HPLC analysis on a Daisopak ODS column. The major product of (Man-G3)-betaCDs was identified as 6-O-alpha-(6(3)-O-alpha-D-mannosylmaltotriosyl)-betaCD by FAB-MS and NMR spectroscopies. The structures of (Man-G3)2-betaCDs were analyzed by TOF-MS and NMR spectroscopies, and confirmed by comparison of elution profiles of their hydrolyzates by alpha-mannosidase and glucoamylase on a graphitized carbon column with those of the authentic di-glucosyl-betaCDs. The structures of three main components of (Man-G3)2-betaCDs were identified as 6(1),6(2)-, 6(1),6(3)- and 6(1),64-di-O-(63-O-alpha-D-mannosyl-maltotriosyl)-betaCD.
Kitahata
S
S
Osaka Municipal Technical Research Institute, Japan. kitahata@omtri.city.osaka.jp
Tanimoto
T
T
Okada
Y
Y
Ikuta
A
A
Tanaka
K
K
Murakami
H
H
Nakano
H
H
Koizumi
K
K
D003505:Cyclodextrins / Q000138:chemical synthesis* / Q000737:chemistry*; D021902:Enterobacter aerogenes / Q000201:enzymology; D006026:Glycoside Hydrolases / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D047392:beta-Cyclodextrins
D003505:Cyclodextrins; D047392:beta-Cyclodextrins; D006026:Glycoside Hydrolases; C100181:pullulanase; C031215:betadex