Re: Food colorings in histology
Dr. Alexander Nader at the Path. Institut Hanuschkrankenhaus in Vienna,
>>Black elder (elderberry, Sambucus nigra) was used sometimes instead of
haematoxylin in Germany and Austria but I have no idea what it contains. It's
still used for marmelade (I actually prefer Grandma's brand) and for
"colour-intensification" of (cheap) red wine. It stains VERY WELL, especially
white shirts and silk ties ;-) <<
R.D. Lillie (in H.J. Conn's Biological Stains, 9th ed. 1977) writes that
"the black elderberry Sambucus niger... was shown to be a mixture of cyanidin
mono- and di- glucosides and galactosides... (Karrer P and Widmer R.
Untersuchungen über Pflanzenfarbstoffe . I. Über die Konstitution einiger
Anthocyanidine. Helv. Chim. Acta 1927;10:5-83.)
Kappers (Kappers CUA. Zellfärbung von chromierten Material mittels
Holunderbeerensaft. Z. Wiss. Mikrosk. 1911;28:416-424) crushed black
elderberries and fermented them 4 days at 26 C., later at 20 C. He then
decanted the supernatant, extracted the residue with hot distilled water, and
combined the two fluids. Protein was coagulated and removed. Iron chloride,
iron alum, and potash alum premordants were tried; FeCl3 was best. Metachrome
mixtures weakened the stain. Overnight staining in a carbol aniline solution
followed by FeCl3 afterchroming gave the best results, comparable with a good
carmine stain for axons, cell bodies, and nuclei."
Hoffentlich sind diese alte Zeitschriften noch in Wien erhältlich!
I hope the fabled Veltliner grape was never so dishonored!
Knoxville, Tennessee USA
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