Constituents of the leaves of Helinus ovatus / by John Augustus Goodson.

  • Goodson, John Augustus.
Date:
1920.]
Catalogue details

Licence: Public Domain Mark

Credit: Constituents of the leaves of Helinus ovatus / by John Augustus Goodson. Source: Wellcome Collection.

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    found in a number of plants, such as the acorns of the common oak and the leaves of Cocos plumosa and C. nucifera. The occurrence of scyllitol, the second of the two known meso- inositols, in these plants is of considerable biological interest in view of the suggestion made by Winterstein, Contardi, and others (compare Posternak, Compt. rend., 1919, 169, 37) that phytin, which is believed to be the usual organic phosphorus reserve con¬ stituent of plants, is a raesoinositol hexaphosphate. The material came from Komgha, Cape Province, and was sup¬ plied by Mr. I. B. Pole Evans, Chief of the Division of Botany, Union of South Africa, who stated that it is used medicinally by the natives, and is known locally as “ soap-plant/’ since the leaves have the property of yielding a lather when rubbed in the hands with water. Preliminary Exa/mination. The leaves contained 9'5 per cent, of moisture and 9’2 per cent, of ash, of which 20’2 per cent, was potash (K20), equivalent to 1*8 per cent, in the leaves. No alkaloid or cyanogenetic glucoside could be detected by the usual reagents. The finely ground leaves gave the following percentages of extract on exhaustion in a Soxhlet apparatus with solvents in the order named: petroleum (b. p. 35—60°), 2'2; ether, 2'3; chloro¬ form, 2-2; alcohol, 23-0. Isolation of Ceryl Alcohol. The petroleum extract consisted of brown, waxy matter, of which about one-third remained undissolved when digested with ether. This was boiled with alcoholic potassium hydroxide solution to remove traces of oil and wax. The residue left after removal of the alcohol was crystallised from ethyl acetate, and then melted at 78°; a specimen of ceryl alcohol melted at 81° in the same bath, and a mixture of the two at 79°. (Found: C = 82-0; H = 14-0. Ceryl alcohol, C26H540 [Henriques, Ber., 1897, 30, 1415], requires C = 8P6; H = 14*2 per cent.) The remaining extracts were systematically examined, with results which showed that the quantity of plant available (650 grams) could best be dealt with by extraction with chloroform to remove wax and resinous matter, and then in succession with alcohol and water.