Die spezifische Drehung des Sorbits und des Sorbit‐Molybdat‐Komplexes

Abstract

The Specific Rotation of Sorbitol and of the Sorbitol Molybdate Complex.I ) The specific rotation of the hexite at 365, 405, 436, 546 and 578 n m has been determined in solutions of different concentration with a commercial sorbitol preparation as well as with a selfproduced sorbitol. Contents of both preparations had been determined enzymatically and by means of periodate. The specific rotation [all) was obtained mathematically from these data as well as b y graphic extrapolation.2) Conditions, under which the sorbitol molybdate complex shows its maximum of specific rotation were defined b y systematic experiments at varying sorbitol, molybdate and hydrogen-ion concentration.3) From these results a diagram was set up, which shows the molybdate and acid doses in order to determine sorbitol polarimetrically in the widest possible range. )The specific rotation of the sorbitol molybdate complex was determined at the same wavelengths as that of the sorbitol. I t was also mathematically and graphically extrapolated (Zusammenfassung siehe Seite 351; R t s u m t d la page 3J1) f o r [aID * t. Einleitung

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