ISSN:
1435-1536
Schlagwort(e):
Glycogen
;
optical rotatory dispersion (ORD) spectra
;
rotatory power
;
dispersion constant
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
Notizen:
Abstract The ORD spectra of three types of glycogen in salt solutions at different concentrations, pH and ionic strength values were determined to investigate the influence of these variables on the rotatory power. The ORD curves obtained with the samples recently prepared correspond to positive monotone dispersion curves, similar to available data for the other polysaccharides. Once the mutarotation equilibrium is attained a maximum is observed at 210±10 nm. The rotatory power decreases with the elapsed time and in some cases, it is possible to find a change in the sign of these curves. Such a phenomenon may be attributed to conformational changes in the monomer units constituting the macromolecule. A considerable increase in the rotatory power is found at pH extreme values. The dispersion constant,λ c , was calculated by means of a modified Drude equation and results indicate that theλ c value is higher for muscle glycogen in the mussel species, suggesting a higher degree of asymmetry in this macromolecule.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01412718
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