Tags

Type your tag names separated by a space and hit enter

Thermal stability of red algal galactans: Effect of molecular structure and counterions.
Int J Biol Macromol. 2017 Nov; 104(Pt A):213-223.IJ

Abstract

Thermal degradation of κ-, ι-, λ-carrageenans, furcellaran, funoran and agarose samples in dry and sol states was investigated. The polysaccharides subjected to heat treatment were characterized by 1H NMR, 13C NMR and FTIR spectroscopy, size exclusion chromatography and static rheometry methods. The microstructure of galactan gels was studied using a cryofixation method in combination with freeze-drying and SEM techniques. Thermal stability at high temperatures decreases in the order of agarose>furcellaran>funoran>κ-carrageenan>λ-carrageenan>ι-carrageenan for dry preparations. The respective sequence for sol state is ι-carrageenan>λ-carrageenan>κ-carrageenan>furcellaran>funoran>agarose. The presence of methoxy groups stabilizes algal polysaccharides whereas divalent cations as counterions increase the susceptibility towards thermal degradation. In dry state the thermal treatment leads to significant desulfation of the galactan before the complete depolymerization occurs. Depending on the sulfation degree and the presence of 3,6-anhydrogalactose residues in the galactan, a notable amount of 5-hydroxymethylfurfural (yield 0.7-21.8%) is formed during the decomposition in sol state.

Authors+Show Affiliations

School of Natural Sciences and Health, Tallinn University, Narva mnt 29, 10120 Tallinn, Estonia.School of Natural Sciences and Health, Tallinn University, Narva mnt 29, 10120 Tallinn, Estonia.School of Engineering, Department of Materials and Environmental Technology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia.School of Engineering, Department of Materials and Environmental Technology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia.School of Natural Sciences and Health, Tallinn University, Narva mnt 29, 10120 Tallinn, Estonia. Electronic address: rtu@akvaarium.com.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

28587967

Citation

Robal, Marju, et al. "Thermal Stability of Red Algal Galactans: Effect of Molecular Structure and Counterions." International Journal of Biological Macromolecules, vol. 104, no. Pt A, 2017, pp. 213-223.
Robal M, Truus K, Volobujeva O, et al. Thermal stability of red algal galactans: Effect of molecular structure and counterions. Int J Biol Macromol. 2017;104(Pt A):213-223.
Robal, M., Truus, K., Volobujeva, O., Mellikov, E., & Tuvikene, R. (2017). Thermal stability of red algal galactans: Effect of molecular structure and counterions. International Journal of Biological Macromolecules, 104(Pt A), 213-223. https://doi.org/10.1016/j.ijbiomac.2017.05.175
Robal M, et al. Thermal Stability of Red Algal Galactans: Effect of Molecular Structure and Counterions. Int J Biol Macromol. 2017;104(Pt A):213-223. PubMed PMID: 28587967.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Thermal stability of red algal galactans: Effect of molecular structure and counterions. AU - Robal,Marju, AU - Truus,Kalle, AU - Volobujeva,Olga, AU - Mellikov,Enn, AU - Tuvikene,Rando, Y1 - 2017/06/03/ PY - 2017/02/28/received PY - 2017/05/20/revised PY - 2017/05/30/accepted PY - 2017/6/8/pubmed PY - 2018/5/3/medline PY - 2017/6/8/entrez KW - Carrageenan KW - Sulfated galactan KW - Thermal stability SP - 213 EP - 223 JF - International journal of biological macromolecules JO - Int J Biol Macromol VL - 104 IS - Pt A N2 - Thermal degradation of κ-, ι-, λ-carrageenans, furcellaran, funoran and agarose samples in dry and sol states was investigated. The polysaccharides subjected to heat treatment were characterized by 1H NMR, 13C NMR and FTIR spectroscopy, size exclusion chromatography and static rheometry methods. The microstructure of galactan gels was studied using a cryofixation method in combination with freeze-drying and SEM techniques. Thermal stability at high temperatures decreases in the order of agarose>furcellaran>funoran>κ-carrageenan>λ-carrageenan>ι-carrageenan for dry preparations. The respective sequence for sol state is ι-carrageenan>λ-carrageenan>κ-carrageenan>furcellaran>funoran>agarose. The presence of methoxy groups stabilizes algal polysaccharides whereas divalent cations as counterions increase the susceptibility towards thermal degradation. In dry state the thermal treatment leads to significant desulfation of the galactan before the complete depolymerization occurs. Depending on the sulfation degree and the presence of 3,6-anhydrogalactose residues in the galactan, a notable amount of 5-hydroxymethylfurfural (yield 0.7-21.8%) is formed during the decomposition in sol state. SN - 1879-0003 UR - https://www.unboundmedicine.com/medline/citation/28587967/Thermal_stability_of_red_algal_galactans:_Effect_of_molecular_structure_and_counterions_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0141-8130(17)30708-0 DB - PRIME DP - Unbound Medicine ER -