High resolution 13C-n.m.r. spectroscopy of 'mixed linkage' xylans
Three xylan fractions, obtained by stepwise precipitation with ethanol, were analysed by 75-MHz 13C-n.m.r. spectroscopy. Diad frequencies, determined from the C-2 resonances, show that the (1 → 3)-linkages are interspersed throughout the chain rather than grouped contiguously. This type of distribut...
Guardado en:
| Autor principal: | |
|---|---|
| Otros Autores: | , , |
| Formato: | Capítulo de libro |
| Lenguaje: | Inglés |
| Publicado: |
1992
|
| Materias: | |
| Acceso en línea: | Registro en Scopus DOI Handle Registro en la Biblioteca Digital |
| Aporte de: | Registro referencial: Solicitar el recurso aquí |
| Sumario: | Three xylan fractions, obtained by stepwise precipitation with ethanol, were analysed by 75-MHz 13C-n.m.r. spectroscopy. Diad frequencies, determined from the C-2 resonances, show that the (1 → 3)-linkages are interspersed throughout the chain rather than grouped contiguously. This type of distribution is in agreement with a random coil conformation and with the constancy of the optical rotation in solvents of different ionic strength and chaotropic power. These diad frequencies were compared with the theoretical values calculated for a random distribution from the ratio of (1 → 4)-:(1 → 3)-linkages in the 1H-n.m.r. spectra, and from the methylation analysis for one of the fractions. © 1992 Butterworth-Heinemann Limited. |
|---|---|
| Bibliografía: | Guiry, A Preliminary Consideration of the Taxonomic Position of Palmaria Palmata (Linnaeus) Stackhouse = Rhodymenia Palmata (Linnaeus) Greville (1974) Journal of the Marine Biological Association of the United Kingdom, 54, p. 509 Usov, Yarotsky, Shashkov, Tishchenko, (1978) Bioorg. Khim., 4, p. 57 Kovač, Hirsch, Shashkov, Usov, Yarostky, 13C-n.m.r. spectra of xylo-oligosaccharides and their application to the elucidation of xylan structures (1980) Carbohydrate Research, 85, p. 177 Björndal, Eriksson, Garegg, Lindberg, Swan, Studies on the Xylan from the Red Seaweed Rhodymenia palmata. (1965) Acta Chemica Scandinavica, 19, p. 2309 Turvey, Williams, (1970) Phytochemistry, 9, p. 2383 Adams, Furneaux, Miller, Whitehouse, Xylan from Leptosarca simplex and Carrageenans from Iridea, Cenacrum and Nemastoma Species from the Subantarctic Islands of New Zealand (1988) Botanica Marina, 31, p. 9 Usov, Adamyants, Yarotsky, Anoshina, Kochetkov, (1974) Zh Obshch Khim., 44, p. 416 Cerezo, Lezerovich, Labriola, Rees, (1971) Carbohydr. Res., 19, p. 289 Cerezo, (1972) Carbohydr. Res., 22, p. 209 Nunn, Parolis, Russell, (1973) Carbohydr. Res., 26, p. 169 Usov, Yarotsky, Estevez, (1981) Bioorg. Khim., 7, p. 1261 Usov, Dobkina, (1988) Bioorg. Khim., 14, p. 642 Manzi, Cerezo, Shoolery, (1986) Carbohydr. Res., 148, p. 189 Gupta, Grasdalen, (1989) Carbohydr. Res., 188, p. 239 Grasdalen, Larsen, Smidsrød, (1981) Carbohydr. Res., 89, p. 179 Grasdalen, (1983) Carbohydr. Res., 118, p. 255 Hakomori, (1964) J. Biochem. (Tokyo), 55, p. 205 Lindberg, (1972) Methods Enzymol., 28, p. 178 Vold, Waugh, Klein, Phelps, Measurement of Spin Relaxation in Complex Systems (1968) The Journal of Chemical Physics, 48, p. 3831 Biely, Vršanská, (1983) Eur. J. Biochem., 129, p. 645 Bock, Pedersen, Pedersen, (1984) Adv. Carbohydr. Chem. Biochem., 42, p. 193 |
| ISSN: | 01418130 |
| DOI: | 10.1016/S0141-8130(05)80016-9 |