Spektrometrische Messungen an Carotinoiden

Abstract

gemacht werden muss, dass die Zeiten in Sekunden ausgedruckt sind. Im Anschluss an eine quantitative Untersuchung iiber die Caw-Price-Reaktion verschiedener Carotinoide sind die Absorptionsmaxima der Mischungen der Carotinoide mit Antimontrichlorid in Chloroform spektrometrisch gemessen worden. Minuten und nicht in

The Carotenoid Pigment Zeaxanthin—A Review

“…Zeaxanthin dissolves in concentrated sulfuric acid with a fairly stable deep blue coloration. On treating a solution of the pigment in chloroform with antimony trichloride, a blue coloration is produced (Euler and others 1930).…”

Vitamin a in Eye Tissues

“…The initial blue color is due to selective absorption of the longer wave lengths of the visible spectrum, specific for each carotenoid. In this test vitamin A may be distinguished easily from all the other known members of the group through its absorption band at about 620 m#, since no other natural carotenoid yields bands above 590 m/z (von Euler, Karrer, Klussmann, and Morf, 1932). The vitamin A absorption at 620 m# falls rapidly after the antimony trichloride has been added, while in impure preparations secondary bands appear at shorter wave lengths, which cause a red color in later stages of the reaction (Wokes, 1928).…”

“…Absorption Spectrum.--Chloroform solutions of vitamin A possess a single broad absorption band in the near ultraviolet, the maximum of which is at 328 m#. The remaining natural carotenoids--except hepaxanthin, with a band at 270 m#--all have absorption bands in the visible spectrum, lying between 400 and 500 m# (von Euler, Karrer, Klussmann, and Morf, 1932). The 328 m# band thus distinguishes vitamin A clearly from the other carotenoids.…”

Variations in the quality of butter, particularly in relation to the vitamin A, carotene and xanthophyll content as influenced by feeding artificially dried grass to stall-fed cattle

“…The respective intensities can be expressed as El°l-617mu = 250 and 585m,u = 192 (for spectroscopic measurements on a number of carotenoids, cf. Euler et al [1932]). The data on the pure substances are summarised in Table I.…”