Tomofuji Y, Yoshiba K, Christensen BE, Terao K Single-chain conformation of carboxylated schizophyllan, a triple helical polysaccharide, in dilute alkaline aqueous solution Polymer185 (2019)
ID 121944
Publication DOI:10.1016/j.polymer.2019.121944 Journal NLM ID:0357015 Publisher: Oxford: Elsevier Correspondence: Yoshiba K <yoshibagunma-u.ac.jp>; Terao K <kteraochem.sci.osaka-u.ac.jp> Institutions: Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Japan, Division of Molecular Science, Graduate School of Science and Technology, Gunma University, Kiryu, Japan, NOBIPOL, Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
Synchrotron-radiation small-angle X-ray scattering measurements were carried out for a schizophyllan (SPG) sample with the weight-average molar mass Mw of 340 kg/mol and five carboxylated SPG (sclerox) samples with different degrees of substitution (DS) ranging from 0.18 to 0.45 in 200 mM aqueous NaOH including 10 mM NaCl to determine Mw, the second virial coefficient A2, the particle scattering function P(q), and the radius of gyration . Positive A2 values indicated that this alkaline solvent was a good solvent for all polysaccharide samples investigated. The resultant Mw values (~100 kg/mol) were much smaller than that for the trimer in aqueous NaCl at neutral pH, indicating all SPG and sclerox samples dissolved as single chains in the alkaline solvent. Both P(q) and were consistently explained by the wormlike chain model. The obtained parameters were almost independent of DS. While the chain stiffness (12–18 nm) in terms of the Kuhn segment length or twice the persistence length was similar to those for the other single chain polysaccharides, the helix pitch per residue (0.1 nm) was quite smaller than the trimer state (0.3 nm). This shrunken main-chain helical structure is most likely due to hydrophobic interactions between helical main chain and side groups.
Tomofuji Y, Yoshiba K, Christensen BE, Terao K Single-chain conformation of carboxylated schizophyllan, a triple helical polysaccharide, in dilute alkaline aqueous solution Polymer185 (2019)
ID 121944
/Variants 0/-+
|
-3)-b-D-Glcp-(1-3)-b-D-Glcp-(1-3)-b-D-Glcp-(1-
/Variants 0/ is:
b-D-Glcp-(1-6)-
OR (exclusively)
GroA-(2-2)-Subst-(2-6)-
Subst = 2,2-dihydroxyacetic acid = SMILES O=C(O){2}C(O)O
Publication DOI:10.1016/j.polymer.2019.121944 Journal NLM ID:0357015 Publisher: Oxford: Elsevier Correspondence: Yoshiba K <yoshibagunma-u.ac.jp>; Terao K <kteraochem.sci.osaka-u.ac.jp> Institutions: Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Japan, Division of Molecular Science, Graduate School of Science and Technology, Gunma University, Kiryu, Japan, NOBIPOL, Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
Synchrotron-radiation small-angle X-ray scattering measurements were carried out for a schizophyllan (SPG) sample with the weight-average molar mass Mw of 340 kg/mol and five carboxylated SPG (sclerox) samples with different degrees of substitution (DS) ranging from 0.18 to 0.45 in 200 mM aqueous NaOH including 10 mM NaCl to determine Mw, the second virial coefficient A2, the particle scattering function P(q), and the radius of gyration . Positive A2 values indicated that this alkaline solvent was a good solvent for all polysaccharide samples investigated. The resultant Mw values (~100 kg/mol) were much smaller than that for the trimer in aqueous NaCl at neutral pH, indicating all SPG and sclerox samples dissolved as single chains in the alkaline solvent. Both P(q) and were consistently explained by the wormlike chain model. The obtained parameters were almost independent of DS. While the chain stiffness (12–18 nm) in terms of the Kuhn segment length or twice the persistence length was similar to those for the other single chain polysaccharides, the helix pitch per residue (0.1 nm) was quite smaller than the trimer state (0.3 nm). This shrunken main-chain helical structure is most likely due to hydrophobic interactions between helical main chain and side groups.
Ma H, Huang Q, Ren J, Zheng Z, Xiao Y Structure characteristics, solution properties and morphology of oxidized yeast β-glucans derived from controlled TEMPO-mediated oxidation Carbohydrate Polymers250 (2020)
ID 116924
NCBI PubMed ID:33049838 Publication DOI:10.1016/j.carbpol.2020.116924 Journal NLM ID:8307156 Publisher: Elsevier Correspondence: Huang Q <whuhqlgmail.com>; Huang Q <hqlmail.hzau.edu.cn> Institutions: College of Food Science and Technology, MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan, China
This work was to investigate the effect of the degree of oxidation (DO) on the structure, solution properties and morphology of yeast β-glucan. Five different degrees of oxidized yeast β-glucan (OYG1-5) samples were controllably prepared by TEMPO-mediated oxidation on C-6 position. Namely, the -CH2OH units were oxidized into -COO-/-COOH, and the DO was quantified to be 10.0~71.2% by potentiometric titration. With an increase of the DO, the OYG samples had a remarkable increase in solubility as indicated by the decreasing turbidity, particle size and zeta-potential, and showed an overall decrease from 2630000 to 143000 g/mol in molecular weight and from 3.95 to 1.66 in polydispersity. OYG1-4 with DO from 10.0% to 47.3% had aggregate morphology with different sizes, while OYG5 with DO of 71.2% showed uniformly dispersed chains and a loose network formed by chain entanglement. These findings demonstrated that the solution properties and morphology of yeast β-glucan can be altered by adjusting the DO
Ma H, Huang Q, Ren J, Zheng Z, Xiao Y Structure characteristics, solution properties and morphology of oxidized yeast β-glucans derived from controlled TEMPO-mediated oxidation Carbohydrate Polymers250 (2020)
ID 116924
NCBI PubMed ID:33049838 Publication DOI:10.1016/j.carbpol.2020.116924 Journal NLM ID:8307156 Publisher: Elsevier Correspondence: Huang Q <whuhqlgmail.com>; Huang Q <hqlmail.hzau.edu.cn> Institutions: College of Food Science and Technology, MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan, China
This work was to investigate the effect of the degree of oxidation (DO) on the structure, solution properties and morphology of yeast β-glucan. Five different degrees of oxidized yeast β-glucan (OYG1-5) samples were controllably prepared by TEMPO-mediated oxidation on C-6 position. Namely, the -CH2OH units were oxidized into -COO-/-COOH, and the DO was quantified to be 10.0~71.2% by potentiometric titration. With an increase of the DO, the OYG samples had a remarkable increase in solubility as indicated by the decreasing turbidity, particle size and zeta-potential, and showed an overall decrease from 2630000 to 143000 g/mol in molecular weight and from 3.95 to 1.66 in polydispersity. OYG1-4 with DO from 10.0% to 47.3% had aggregate morphology with different sizes, while OYG5 with DO of 71.2% showed uniformly dispersed chains and a loose network formed by chain entanglement. These findings demonstrated that the solution properties and morphology of yeast β-glucan can be altered by adjusting the DO
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gunma-u.ac.jp>; Terao K <kterao