Movatterモバイル変換

[0]ホーム
URL:

Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
Thehttps:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

NIH NLM Logo
Log inShow account info
Access keysNCBI HomepageMyNCBI HomepageMain ContentMain Navigation
pubmed logo
Advanced Clipboard
User Guide

Full text links

MDPI full text link MDPI Free PMC article
Full text links

Actions

Share

.2011 Sep 2;16(9):7488-501.
doi: 10.3390/molecules16097488.

Thermal and rheological properties of a family of botryosphaerans produced by Botryosphaeria rhodina MAMB-05

Affiliations

Thermal and rheological properties of a family of botryosphaerans produced by Botryosphaeria rhodina MAMB-05

Paulo R M S Fonseca et al. Molecules..

Abstract

Differential scanning calorimetry (DSC), thermogravimetry (TG) and Fourier-transform infra-red spectroscopy (FT-IR) analyses were performed to investigate changes in the physico-chemical properties of botryosphaerans, a family of exopolysaccharides (EPS) produced by the fungus Botryosphaeria rhodina MAMB-05 grown on glucose (EPS(GLC)), sucrose (EPS(SUC)) and fructose (EPS(FRU)). A slight endothermic transition and small mass loss attributable to the removal of water of hydration were observed in the DSC and TG analyses, respectively, for the three EPS samples. The FT-IR spectra confirmed no structural changes occurred during thermal treatment. Viscometry was utilized to obtain information on the rheological behaviour of the EPS in aqueous solutions. The Power Law and Cross Equations determined the natural pseudoplastic characteristics of the EPS. Comparatively, results obtained for EPS produced when B. rhodina MAMB-05 was grown on each of the three carbohydrate sources demonstrated similar apparent viscosity values for EPS(GLC) and EPS(SUC), while EPS(FRU) displayed the lowest apparent viscosity of the three botryosphaerans, suggesting a higher degree of ramification and lower Mw. EPS(GLC) and EPS(SUC) possessed similar degrees of ramification. The slight differences found in their viscosities can be explained by the differences in the type of branching among the three botryosphaerans, thus varying the strength of intermolecular interactions and consequently, consistency and viscosity. The physico-chemical studies of botryosphaerans represent the originality of this work, and the knowledge of these properties is an important criterion for potential applications.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
DSC (—) and DDSC (---) curves for botryosphaerans EPSGLC, EPSSUC and EPSFRU over the 50–150 °C temperature range. The heating rate was 5 °C/min, with an isothermal hold at 150 °C for 30 min.
Figure 2
Figure 2
TG (—) and DTG (---) curves for botryosphaerans EPSGLC, EPSSUC and EPSFRU within the 30–150 °C temperature range. The heating rate was 5 °C/min, with an isothermal hold at 150 °C for 30 min.
Figure 3
Figure 3
FT-IR Spectra for botryosphaerans EPSGLC, EPSSUC and EPSFRU before analysis (---), after TG (___) and after DSC (….), showing the characteristic bands of glucosidic linkages.
Figure 4
Figure 4
The apparent viscosity (η)versus shear rate (γ) in log scale for botryosphaerans at different concentrations: 1.0 g/L (-★-), 2.0 g/L (-▭-), 3.0 g/L(-▲-), 4.0 g/L (-○-) and 5.0 g/L (-■-). a) EPSGLC; b) EPSSUC; c) EPSFRU. The inset EPSFRU graph is shown on a different scale to demonstrate “shear thinning” of EPSFRU.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Villain-Simonnet A., Milas M., Rinaudo M. A new polysaccharide (YAS34). I. Characterization of the conformations and conformational transition. Int. J. Biol. Macromol. 2000;27:65–75. doi: 10.1016/S0141-8130(99)00120-8. - DOI - PubMed
    1. Zohuriaan M.J., Shokrolahi F. Thermal studies on natural and modified gums. Polym, Test. 2004;23:575–579. doi: 10.1016/j.polymertesting.2003.11.001. - DOI
    1. Selbmann L., Stingele F., Petruccioli M. Exopolysaccharide production by filamentous fungi: The example of Botryosphaeria rhodina. Antonie Leeuw. 2003;84:135–145. doi: 10.1023/A:1025421401536. - DOI - PubMed
    1. Ikeda S., Nitta Y., Kim S.B., Temsiripong T., Pongsawatmanit R., Nishinari K. Single-phase mixed gels of xyloglucan and gellan. Food Hydrocoll. 2004;18:669–675. doi: 10.1016/j.foodhyd.2003.11.005. - DOI
    1. Wolkers W.F., Oliver A.E., Tablin F., Crowe J.H. A Fourier-transform infrared spectroscopy study of sugar glasses. Carbohydr. Res. 2004;339:1077–1085. doi: 10.1016/j.carres.2004.01.016. - DOI - PubMed

Publication types

MeSH terms

Substances

Related information

LinkOut - more resources

Full text links
MDPI full text link MDPI Free PMC article
Cite
Send To

NCBI Literature Resources

MeSHPMCBookshelfDisclaimer

The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). Unauthorized use of these marks is strictly prohibited.

[8]ページ先頭
©2009-2025 Movatter.jp