Chemical examination of the fruit of Brucea antidysenterica / by Frederick B. Power and Arthur H. Salway.

  • Frederick Belding Power
Date:
[1907]
Catalogue details

Licence: In copyright

Credit: Chemical examination of the fruit of Brucea antidysenterica / by Frederick B. Power and Arthur H. Salway. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    'mass. The mixture was then ■ (iistilled in steam, and a very small amount of volatile acid thus obtained, which, after con- Xtersion into a barium salt, afforded the reactions of acetic and hvMjric acids. The acids remaining in the distilling flask were extracted with chloroform, the resulting solution washed with water, dried with calcium chloride, and the solvent removed, the last traces of cliloroform being expelled by heating on a water bath under diminished pressure. About 250 Gm. of mixed fatty acids were thus obtained, the constants of which were determined with the following results —Melting point 27-28° C. ; specific gravity 30°/30°C.=0'8980 ; iodine value=83'5 ; acid value = 186T ; acetyl value=4'5. From the iodine value, as determined by Hubl’s method, it was concluded that the mixture consisted largely of unsaturated acids, oleic acid, for example, having an iodine value of 90'1. On the other hand, the acid value 186T indicated that only a small quantity of acids having a higher molecular weight than stearic and oleic acids were })resent, the acid values of the latter two acids being 197'5 and 198’9 respectively. In order to separate the constituents of the mixed fatty acids, the solid portion, amounting to about 50 Gm., was first removed by filtration at the pumj). It was fractionally crystallized from alcohol, when the first depo.sits liielted at 60-62° C., but after four successive crystallizations melted constantly at 69’5° C. This was evidently a pure substance, and was analysed;— 01710 gave 0 4748 OO2 and 0 2022 H2O. C=75 7 ; H=131, C18H36O2 requires C=76-l ; H=12'7 per cent. This substance w'as thus identified as stearic acid,. The mother liquors resulting from the above fractionation contained a considerable quantity of an acid which, after repeated crystalhzation, .se]iarated in glistening leaflets melting at 57-60° G Although this could not be obtained perfectly pure, it was analysed, with the following result:— 01681 gave 0 4636 C'Oo and 0 1898 H2O. C=75 2 ; H = 12-5. CifiH3202 requires 0 =75 0; H = 12 5 per cent. It is evident that this substance was palmitic acid. The liquid acids, which were separated by filtration from the above-described solid portion, were considerable in amount, the