Journal of Applied Glycoscience
Online ISSN : 1880-7291
Print ISSN : 1344-7882
ISSN-L : 1344-7882
Volume 54, Issue 4
Displaying 1-6 of 6 articles from this issue
Regular Papers
  • Kazutoshi Ogawa, Yoko Ikeda, Kazuyuki Umemura
    2007 Volume 54 Issue 4 Pages 203-209
    Published: 2007
    Released on J-STAGE: December 10, 2007
    JOURNAL FREE ACCESS
    The chemical structure of a new water-absorbing polysaccharide (WAP), which was isolated from a liquid culture of bacterium belonging to the family Oxalobacteraceae, was analyzed by fragmentation analysis and methylation techniques. Mild acid hydrolysis of WAP gave six di-, four tri-, two tetra-, two penta-, and one hexasaccharides composed of mannose, glucose and/or galactose. These structures were elucidated by extensive 2D NMR spectroscopic analyses. The structure of the WAP has been proposed to have a new heptasaccharide as a repeating unit, →4)-β-D-Glcp-(1→4)-β-D-Manp-(1→4)-β-D-Glcp-(1→4)-[β-D-Galp-(1→3)-β-D-Glcp-(1→3)-β-D-Galp-(1→3)]-β-D-Galp-(1→.
    Download PDF (327K)
  • Kazunori Takamine, Jun-ichi Abe, Kaori Shimono, Yoshihiro Sameshima, S ...
    2007 Volume 54 Issue 4 Pages 211-216
    Published: 2007
    Released on J-STAGE: December 10, 2007
    JOURNAL FREE ACCESS
    A novel pectin was extracted from sweet potato (Ipomoea batatas) pulp (SPP) using 50 mM disodium phosphate solution. Uronic acids in the pectin extract were almost completely removed from the supernatant after the addition of 0.3 volumes 95% ethanol. The sweet potato pectin consisted of 64.8% galacturonic acid and small amounts of neutral sugars. The ash concentration was 21.6% and sodium comprised 6.1 g per 100 g of the pectin. The degree of esterification of the pectin was 1.4%. The infrared spectrum of the pectin was similar to that of sodium polypectate. These results indicate that most of the carboxyl groups of the pectin are replaced by sodium. The pectin had average molecular-weights of approximately 7.85×105 and 2.42×105 Da. The viscosity was of the pectin (2%) the 130 mm2/s at 5°C. The effect of extrinsic parameters, such as pH and concentrations of pectin, calcium and sucrose, on the breaking pressure of the pectin gel was evaluated. The results of the breaking pressure analysis of the pectin gel indicate that the pectin has properties typical of low methoxyl pectin.
    Download PDF (369K)
  • Yoshimitsu Matsui, Sanae Okada, Tai Uchimura, Akihiko Kondo, Eiichi Sa ...
    2007 Volume 54 Issue 4 Pages 217-222
    Published: 2007
    Released on J-STAGE: December 10, 2007
    JOURNAL FREE ACCESS
    We analyzed the functional structure of Streptococcus bovis 148 α-amylase (AmyA) to determine the starch binding domain (SBD) of this enzyme. Several derivative AmyAs and putative SBD segments were constructed and assayed their adsorption ability onto raw starch. On the basis of the results, a putative linker domain region and two SBDs (SBDα and SBDβ) were found at the C-terminal region of AmyA. SBDα and SBDβ showed 56% amino acid sequence similarity; these SBDs were considered to be tandem repeat motif. In addition, we constructed a chimeric enzyme CsaB, which consisted of S. bovis 148 irresolvable intracellular α-amylase (AmyB) as for insoluble starch and a putative linker plus two SBDs. This enzyme succeeded in conferring starch adsorption and hydrolysis abilities, which suggests that SBD reacts with the surface of raw starch and breaks down its structure.
    Download PDF (415K)
  • Fiame Leo, Shukichi Hashida, Daiju Kumagai, Kenji Uchida, Hidemasa Mot ...
    2007 Volume 54 Issue 4 Pages 223-229
    Published: 2007
    Released on J-STAGE: December 10, 2007
    JOURNAL FREE ACCESS
    A neutral exopolysaccharide produced in large amounts by Lactobacillus fermentum TDS030603 was purified from culture supernatants and its structure determined by monosaccharide analysis, methylation analysis and 1H-NMR spectroscopy. Optimum conditions for the production of this exopolysaccharide by the above bacterial strain, when cultured using cheese whey medium or MRS broth, were also investigated. The exopolysaccharide was found to be composed of D-galactose and D-glucose in the molar ratio of 1:2.5 and to consist of one major as well as one minor saccharide, both of which contained a tetrasaccharide repeating unit consisting of two α and two β anomers. The major saccharide contained non-reducing glucopyranose, O-3 substituted glucopyranose, O-6 substituted galactopyranose and O-2,3 disubstituted glucopyranose. The minor saccharide consisted of non-reducing galactopyranose, O-3 substituted glucopyranose, O-6 substituted galactopyranose and O-2,3 disubstituted glucopyranose. The results suggest that these exopolysaccharides are novel saccharides that differ from previously reported products of Lactobacillus fermentum strains. Their presence may contribute to the ropy properties of the medium.
    Download PDF (314K)
Note
  • Naoto Kato, Masahiro Mizuno, Yoko Nakai, Kouichi Nozaki, Hiroyuki Suga ...
    2007 Volume 54 Issue 4 Pages 231-233
    Published: 2007
    Released on J-STAGE: December 10, 2007
    JOURNAL FREE ACCESS
    The water-soluble extracellular polysaccharide produced by Asaia bogorensis, an acetic acid bacterium, was investigated. It was suggested that the water-soluble polysaccharide seemed to be a fructan as only fructose was detected as a constituent sugar when it was hydrolyzed by trifluoroacetic acid. To confirm the glycosidic linkage of the fructan, 1H NMR spectroscopy and 13C NMR spectroscopy were carried out. From these results, Asaia fructan was identified as levan, which is a β-2,6 linked fructan, similar to the polysaccharide produced by Gluconacetobacter xylinus. This β-2,6-linked levan-type fructan was produced only when sucrose was used as a carbon source.
    Download PDF (289K)
Review
  • Ken’ichi Ohtsubo, Sumiko Nakamura
    2007 Volume 54 Issue 4 Pages 235-243
    Published: 2007
    Released on J-STAGE: December 10, 2007
    JOURNAL FREE ACCESS
    As the cultivars of rice affect markedly eating quality, processing suitability and price, identification or differentiation of rice cultivars is very important. The present authors developed suitable STS (sequence-tagged-site) primers for PCR (Polymerase Chain Reaction) and it became possible to identify rice cultivars using template DNA extracted and purified from rice grains. A multiplex primer set was shown to be useful to differentiate effectively rice cultivars produced in various countries by PCR. Two kinds of multiplex kit for identification of Koshihikari, the dominant cultivar in Japan, have been developed. The application of the cultivar identification method by PCR to processed rice products was investigated. The present authors developed an “enzyme treatment method,” in which the gelatinized starch is decomposed by the heat-stable α-amylase at 80°C, followed by hydrolysis of proteins by proteinase K with SDS and purification of extracted DNAs by PCI (Phenol/Chloroform/iso-amyl alcohol). It became possible to identify the material rice cultivars of the processed rice products, such as cooked rice and rice cake, by the PCR method using template DNA prepared by the “enzyme treatment method.”
    Download PDF (336K)
feedback
Top