English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

A NUMBER of communications during recent years by Warburg and Christian [1932,1,2] show that besides the iron-containing enzyme ofa haemin nature there exists another enzyme capable of transporting oxygen under aerobic conditions and of dehydrogenation under anaerobic conditions. The scheme of its action is as follows: 1. Leuco-enzyme + oxygen= yellow enzyme + hydrogen peroxide (under aerobic conditions). 2. Leuco-enzyme + methylene blue = yellow enzyme + leucomethylene blue (under anaerobic conditions). The power of flavins to oxidise by means of dehydrogenation has also been confirmed by Wagner-Jauregg et al. [1934] and by Adler and Euler [1934]. Freed from its colloidal carrier the yellow oxidation enzyme is identical with the flavin discovered and described in the same year by Kuhn et al. [1933, 1, 2] and simultaneously by Ellinger and Koschara [1933]. These same authors have shown in their investigations that the flavins are quite similar to vitamin B2 in their action on the organism, and this makes these compounds the more important. Notwithstanding the great biological significance of the flavins, there do not exist sufficiently precise methods for their determination in animal tissues and organs. Gy6rgy et al. [1934] have drawn up a table of the flavin content of tissues according to their degree of action as carriers of vitamin B2. Euler and Adler [1934] have compared the intensities of the colour of aqueous extracts from different tissues with a standard scale of solutions of flavins in different concentrations. The data obtained by Euler agree well with the data obtained by Gyorgy et al. These methods however do not supply absolute values of the flavin content, but give only approximations. We believe the method of Warburg and Christian [1933] to give more exact determinations. These authors consider it possible to calculate the concentration of flavins by the intensity of the absorption spectra of methanol extracts. This method of determination is however hardly available for most laboratories as it requires complicated equipment; we have therefore modified it by substituting colorimetry for spectrophotometry.

Flavin content of animal tissues under different conditions