SOME PHYSICAL AND CHEMICAL PROPERTIES OF XAN- 
THOPHYLL AND THE PREPARATION OF THE PURE 
PIGMENT 1 
By F. M. Schertz, 
Associate Biochemist in Soil Fertility Investigations, Bureau of Plant Industry, 
United States Department of Agriculture 
INTRODUCTION 
Xanthophyll when found in plant 
materials is associated with carotin. 
It is present in all green plants along 
with carotin, but in larger quantity. 
Much has been published regarding 
the carotinoids, but as^ methods of 
isolating the pigments have differed 
somewhat from time to time, it is 
difficult to say whether xanthophyll 
was or was not present in any given 
plant or animal material reported in the 
literature. It has been definitely esta¬ 
blished that xanthophyll or its isomer 
is present in hen eggs and in the body 
fat of chickens (7), 2 and also in yellow 
corn. Gill (3) claimed that a relatively 
small amount of the pigment in yellow 
corn is carotin, although Palmer and 
Kempster (7) and Palmer and Eckles 
(6) showed that yellow corn is rich in 
xanthophyll and that a little of the 
pigment is found in hemp seed, barley, 
gluten feed, and red corn. 
Some of the work reported in the 
literature has not been done with 
sufficient accuracy to warrant a state¬ 
ment regarding the amount of xantho¬ 
phyll present in certain plant and 
animal substances. Very often, too, 
xanthophyll is confused with carotin 
and vice versa, and sometimes it is 
known under another name, the name 
given being entirely misleading, for it 
is only recently that reliable methods 
of procedure have been worked out 
for the separation (12) and complete 
identification of these two pigments. 
Even in the more recent literature 
statements regarding the carotinoids 
are often difficult to explain'. Gill (5) 
states that none of the pigments of 
yellow corn, mustard, and orange peel 
are extracted from a petroleum ether 
solution by 80 to 90 per cent alcohol, 
although large amounts are absorbed 
by calcium carbonate. Since none of 
the pigments are extracted by the 
alcohol it would appear that xantho¬ 
phyll is not present, and again, since 
adsorption by calcium carbonate is 
large, it appears that the pigment is 
xanthophyll. Another instance of 
seemingly contradictory results can be 
found in the work of Palmer and Eckles 
(6, p. 362), if the standards set by 
Tswett (10) regarding xanthophyll are 
accepted; the xanthophy 11-like con¬ 
stituents of yellow corn were not 
adsorbed by calcium carbonate from a 
carbon disulphide or a petroleum ether 
solution and, on the other hand, the 
pigments could be completely ex¬ 
tracted from a petroleum ether solution 
by 80 per cent methyl alcohol. 
Here are two cases of xanthophyll 
behavior which do not agree with the 
generally accepted idea of its behavior. 
The xanthophyll reported by Gill could 
not have been xanthophyll, since it 
was not extractable by alcohol, while 
that reported by Palmer and Eckles 
would be xanthophyll, according to the 
standard set by Willstatter, since it 
was extractable by 80 per cent alcohol. 
These two cases of conflicting state¬ 
ments make it quite plain that there is 
need of work on the Tswett (10) ad¬ 
sorption method in connection with the 
distribution of carotin and xanthophyll 
between petroleum ether and alcohol. 
It is very desirable that the different 
xanthophylls, as described by Tswett, 
be obtained in crystalline form so that 
the pure pigments, if they really exist, 
may be identified. 
Palmer and Eckles also have shown 
how the xanthophvll-like fraction from 
carrots produces several adsorption 
bands when the carbon disulphide solu¬ 
tion is passed through a calcium car¬ 
bonate adsorption column. The pig¬ 
ment of Zone I appears entirely unlike 
the others, for it is completely adsorbed 
bv calcium carbonate from a carbon 
1 Received for publication June 13, 1924; issued June, 1925. 
2 Reference is made by number (italic) to “Literature cited,” p. 584. 
Journal of Agricultural Research 
Washington, D. C. 
( 575 ) 
Vol. XXX, No. 6. 
Mar. 15, 1925 
Key No. G-479 
TG-479 
