This work reports a chemical and rheological study of the carrageenans from Hypnea musciformis, a red seaweed commercially known for its production of κ-carrageenan. The polysaccharides were extracted with water both at room temperature and at 90 °C: the yield of the latter was about six times larger than the former. Fractionation with KCl yielded a large proportion (50-67%) of a precipitate with 0.125 M of this salt for both extracts, with characteristics of a nearly pure κ-carrageenan, as determined by methylation analysis and NMR spectroscopy. Smaller amounts of fractions precipitating at higher concentrations showed a basic κ-carrageenan structure, but included some ι-carrageenan diads. The KCl-soluble polysaccharides showed a larger complexity, containing d- and l-galactans or d/l-hybrids. Some differences in the rheological properties of these carrageenans have been found. Although all KCl-precipitating polysaccharides form true gels at 10 °C in presence of KCl, those extracted with hot water form stronger gels than those extracted at room temperature. Both purified κ-carrageenans show lower gelling and melting temperature than the whole polysaccharides from which they were originated. © 2013 Elsevier Ltd. All rights reserved.
Documento: | Artículo |
Título: | Chemical and rheological characterization of the carrageenans from Hypnea musciformis (Wulfen) Lamoroux |
Autor: | Cosenza, V.A.; Navarro, D.A.; Fissore, E.N.; Rojas, A.M.; Stortz, C.A. |
Filiación: | Departamento de Química Orgánica-CIHIDECAR, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina |
Idioma: | Inglés |
Palabras clave: | κ-Carrageenan; Carrageenans; Dynamic oscillatory; Rheology |
Año: | 2013 |
DOI: | http://dx.doi.org/10.1016/j.carbpol.2013.10.090 |
Título revista: | Carbohydrate Polymers |
Título revista abreviado: | Carbohydr Polym |
ISSN: | 01448617 |
CODEN: | CAPOD |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01448617_v_n_p_Cosenza |