The constituents of taraxacum root / by Frederick B. Power and Henry Browning, jun.
- Frederick Belding Power
- Date:
- [1912?]
Licence: Public Domain Mark
Credit: The constituents of taraxacum root / by Frederick B. Power and Henry Browning, jun. Source: Wellcome Collection.
20/24 page 2428
![Summary and Conclusions. The material employed for this investigation consisted of the air-dried, fresh roots of taraxacum (Taraxacum officinale, Wiggers), collected in the autumn from plants grown in England. The roots were found to contain a very small amount of an enzyme, which slowly hydrolysed amygdalin. An alcoholic extract of the root, when distilled in a current of steam, yielded a small amount of a yellow essential oil. From the portion of the extract which was soluble in water, the following substances were isolated: (i) ^^-hydroxyphenylacetic acid, CgHgOg (m. p. 144—146°); (ii) 3: 4-dihydroxycinnamic acid, C9H8O4 (m. p. 214—216°); (iii) a small amount of choline, C5H15O2N, which was identified by its gold and platinum compounds. The aqueous liquid contained, furthermore, a considerable quantity of a Isevorotatory sugar, which appeared to consist chiefly, if not entirely, of Isevulose, and yielded an osazone, melting at 204—206°. The portion of the alcoholic extract which was insoluble in water consisted of a soft, oily resin, which amounted to 1*8 per cent, of the weight of the root. From this material the following compounds were isolated: (i) a new monohydric alcohol, taraxa- sterol, C29H47*0H (m. p. 221—222°; [ajj, -f96'3°), which yielded an acetyl derivative (m. p. 251—252°; [a]j) -p 122*2°), a mono- hromoacetyl derivative (m. p. 233—234°), and a benzoyl derivative (m. p. 232°); (ii) a new monohydric alcohol, homotaraxasterol, CgsHgg’OH (m. p. 163—164°; [aJj, -f 25*3°), which yielded an acetyl derivative (m. p. 219—220°; [ajj, -1-28*1°), and a benzoyl derivative (m. p. 202°). The above-mentioned alcohols, together with two previously isolated compounds, androsterol, C3oH49*OH, and homo- androsterol, C27H43'OH (Trans., 1909, 95, 739), constitute an homologous group, which is represented by the general formula CnH2n-ioO. (iii) Cluytianol, C29H460(0H)4, melting at 297° (this vol., p. 2230), from which the tetra-acetyl and tetrabenzoyl derivatives were prepared; (iv) palmitic, cerotic, and melissic acids, together with a mixture of unsaturated acids, consisting chiefly of oleic and linolic acids, with, apparently, a little linolenic acid. The bitter taste of taraxacum, which has hitherto been ascribed to the so-called “ taraxacin,” appears to be due chiefly to dark- coloured, amorphous material, and not to any distinct principle. It was found, for example, that the portion of an alcoholic extract of the root which is soluble in water, when repeatedly extracted with warm amyl alcohol, yielded a viscous product, which possessed an intensely bitter taste.](https://iiif.wellcomecollection.org/image/b30619543_0020.jp2/full/800%2C/0/default.jpg)
