Oct. 13, 1923 
The Constituents of a Chufa" Oil 
81 
The results in column 6 indicate what saturated acids may be present 
in the various fractions. The mean molecular weight of the saturated 
acid esters in fraction 1 is slightly below that of methyl palmitate (270.3), 
and indicates that the fraction is methyl palmitate with a trace of methyl 
myristate. The mean molecular weights of the saturated acid esters of 
fractions 2 to 5 lie between the molecular weights of methyl palmitate and 
methyl stearate (298.4), which indicates that these four fractions contain 
these two esters in various proportions. The probable constituents of 
fractions 6 and 7 are methyl stearate and methyl arachidate (326.4), and 
those of fraction 8 methyl arachidate and methyl lignocerate (328.5). 
The free acids were recovered from some of these fractions and the 
residue by saponifying with alcoholic potash and decomposing the 
resulting soap with hydrochloric acid. The consituent acids were then 
isolated by fractional crystallization from alcohol. Their identity was 
established by the melting points and by observing whether or not these 
melting points were lowered when the substances were mixed with equal 
amounts of the respective acids which they were suspected of being, 
and the purity of which had been established previously by elementary 
analyses. 
In all cases the melting points of the isolated acids confirmed deduc¬ 
tions drawn from the mean molecular weights of the fractions. The fol¬ 
lowing acids were isolated: 
Lignoceric acid, C 24 H 48 0 2 . From the residue 0.14 gm. of fatty acid melting at 
80.5° was obtained. It was also identified in fraction 8. 
Arachidic acid, C 20 H 40 O 2 . This acid was identified in fractions 6 and 7 by the 
melting point 76.5°. 
Stearic acid, C 18 H, 6 0 2 . Isolated from fractions 4, 5, and 6 and identified by the 
melting point 68-69° 
Palmitic acid, C 16 H 32 0 2 . Its presence was proven in fractions 1, 2, and 3 by the 
melting point 63°. 
Myristic acid, C 14 H 28 0 2 . Eight subfractions were obtained from fraction 1 by its 
fractional crystallization from alcohol. The first five subfractions melted at 63°, the 
sixth and seventh at 60-61 °, and the eighth at 54-55°. This eighth subfraction was 
mixed with an equal quantity of myristic acid of known purity and the melting point 
of the mixture taken. It was found to be 54-55°, which proved the eighth subfraction 
to be myristic acid. 
The identity of the saturated acids in the various fractions and the 
residue obtained by distillation having been established, the quantities 
were calculated from the mean molecular weights of the saturated acid 
esters (column 6, Table II) and the theoretical molecular weights of the 
two esters in each fraction. The results are given in columns 7-16, 
Table II. 
TabIvTS III .—Saturated acids 
Acids in saturated 
acid fraction. 
Acids 
in original 
oil. 
Glycerids 
in original 
oil. 
Myristic. 
Gm. 
O. 03 
55 - OS 
24. 21 
2. 70 
1. 25 
Per cent. 
O. 04 
66. 14 
29. 08 
3 - 2 4 
I. 50 
Per cent. 
Trace, 
ii- 3 
5 -o 
• S 
•3 
Per cent. 
Trace. 
11. 8 
5-2 
•S 
•3 
Palmitic. 
Stearic. 
Arachidic. 
Eignoceric. 
83.24 
IOO. 00 
17 - 1 
17.8 
60373—23- i 
