Separation of Fatty Acids by Lithium Salts : 2. Examinations on Water-soluble, -insoluble Lithium Salts

We carried out the experiments on separations of fatty acids by lithium salts, using the oils of vegesable and animal kingdoms (vegetable 14, animal 13 varities). The lithium salts of fatty acids were prepared with Li_2SO_4 and LiOH, then separated roughly into two fractions, namely, water-insoluble and -soluble fractions. The former was further separated by the solubility in alcoho, the latter, after being detached lithium, with petroleum ether and benzene. On the whole, the main fractions were the water, alcohol-insoluble lithium salts, of the water soluble part, mainly the petroleum ether-soluble. However, the amounts of each fractions were indefinite according to the oils ; especially, in the case of the rat's depot fat, a considerable difference was noted by the feeding condition, diets fed the rats. The fatty acids obtained from alcohol-insoble Li-salts were largely solid with some exceptions, being seemed to be C_<16-20> acids from the neutralizatiion values ; noted also the spots of unsaturated fatty acids on the chromatograms. The fatty acids obtained from water-soluble Li-salts were viscous or resinous, in any case, showed an exceptionally lower neutraliation value than others. The sodium hydroxide solutions of these acids disclosed the positive reduction reactions of sugars, namely, Fehling, Benedict, Tollen and Schiff reactions ; carbonyl numbers were variable by the acids. The experimental results of fatty acids by paper chromatography, indicated the plural or single spots. At all events, the fatty acids obtained from the water-soluble Li-salts, were distinguishable from other acids and we take a special interest.