The extraction of “fat-soluble vitamine” from green foods

Abstract

We have recently published experimental data to demonstrate the occurrence of “fat-soluble vitamine” in certain foods. 1 McCollum, Simmonds and Pitz 2 have stated that “ether extraction of plant tibsues does not remove the substances essential for growth which is contained in butter fat.” They further say “owing to the large content of waxes, etc., extracted from plant leaves we have not been very successful in feeding ether extract from these sources.” We have, however, obtained potent preparations as follows: Spinach leaves and young clover respectively, dried in a current of air at about 60°, were extracted with U. S. P. ether. The resultant green extract, yielding an oily residue equal to about 3 per cent. of the dried plant, was evaporated upon starch. These preparations, fed in daily quantities equivalent to 1-2 grams of the dried plant, promoted recovery and renewal of growth in rats declining in weight on diets deficient in fatsoluble vitamine. Inasmuch as only 30 milligrams per day of the ether extract of spinach sufficed for this purpose it appears that this product ranks among the most potent of the oils heretofore tested.