328 MISSOURI AGR. EXP. STA. RESEARCH BULLETIN No. 9. 



of the salmon with the exception that it was very little soluble in 

 methyl alcohol, but dissolved readily in ether. 



General Properties of the Lipochromes. It will not be out of place 

 to give a brief summary here of the general characteristics and prop- 

 erties of the lipochrome pigments as found up to this time. 



Lipochromes 7 may be classed as salve-like, yellow or red or 

 orange colored residues, which have been obtained in needles or 

 rhombic plates, where they have been crystallized. They are soluble 

 in alcohol, ether, benzol, petroleum ether, amyl alcohol, chloroform, 

 carbon bisulphide, ethereal oils and fats with a yellow or yellow- 

 orange color. They are insoluble in cold and hot water and alkalies 

 and dilute acids, but are soluble in alcoholic alkaline solutions and 

 are unchanged when these solvents are heated. In alcohol or other 

 solvents they are unstable,, and readily bleach, as do the residues 

 from these solutions. The bleach product is unknown, but it is cer- 

 tainly not identical with cholesterol. On addition of concentrated 

 H 2 SO 4 or HNO 3 , the lipochromes give a color change of blue-green- 

 violet to brown. The color reactions are often interfered with by the 

 presence of a small amount of foreign substance. The lipochromes 

 generally give a blue-green coloration with a solution of iodine in 

 potassium iodide. Spectroscopically the lipochrome solutions show 

 two bands and sometimes three in the blue part of the spectrum, 

 and again they sometimes show no bands at all. 



The lipochromes may be extracted from the fresh or dried tissues 

 in which they are found, by organic solvents, best by hot or cold 

 alcohol, ether, petroleum ether, carbon bisulphide or chloroform, the 

 choice of the solvent resting with whether some foreign pigment is 

 present. When fat is present, the pigment may be heated with alcoholic 

 alkali which will not saponify the lipochromes. The lipochromes can 

 be extracted from the soap with ether, petroleum ether, or chloroform, 

 either directly or after acidifying, or the lipochromes can be salted out 

 of their alkaline soap solutions with sodium chloride, and the lipo- 

 chromes obtained by extracting the precipitated soap with alcohol or 

 ether. 



The Lipochromes of Algae, Fungi, and Bacteria. While a wide dis- 

 tribution of the lipochromes has already been mentioned, a review 

 of their literature would not be complete without mentioning their 

 distribution in algae, fungi and bacteria. 



1. Summarized from "Lipochromes" by Franz Samuely. Alderhalden's 

 Biochemisches Handlexikon vol. 6, and Handbuch der Biochemischen Arbeits- 

 methoden, vol. 2. 



