Fatty Acid Analysis of Emu Oil
Margaret
C. Craig-Schmidt, Ph.D. Amanda Brown M.S.
Paul
C. Smith, D.V.M., Ph.D. Auburn University
Emu oil has recently received
attention for its possible therapeutic and cosmetic benefits.
The oil of the emu has been used for medicinal purposes by
the Aborigines of Australia for many years and is currently being
used in the cosmetic industry for its protective and softening effects
of the skin. The exact mechanism by which emu oil exerts these effects is
not known. Because
several fatty acids are known to have potent physiological effect,
it is important to characterize emu oil with respect to its fatty
acid composition.
Fatty
acids are classified according to chain length and by the number
of double bonds, or points of unsaturation, in the chain.
For example, palmitic acid is a fatty acid with sixteen carbons
and no double bonds; thus in scientific nomenclature it is abbreviated
as “16.0”.
Because this fatty acid contains no double bonds, it is termed
a “saturated” fatty acid.
Fatty acids with one double bond (one point of unsaturation)
are called “monounsaturated” fatty acids, and those with two or
more double bonds are called “polyunsaturated” fatty acids.
Oleic acid or 18:1 is a common monounsaturated fatty acid,
and linoleic acid or 18:2 is a common polyunsaturated fatty acid.
Any natural fat contains a mixture of all three types of
fatty acids attached to a glycerol “backbone”.
These compounds are called triglycerides.
If a fat contains triglycerides made up of mostly saturated
fatty acids, such as palmitic acid, then this fat is called a saturated
fat.
The health
effects of different types of fatty acids are well established.
For example, saturated fat in the diet is known to raise
blood cholesterol, but monounsaturated fats and polyunsaturated
fats are known to lower blood cholesterol levels and thus reduce
one’s risk for cardiovascular disease.
Some polyunsaturated fatty acids are called “essential fatty
acids” because they are necessary for the proper functioning of
the body yet cannot be made by the body.
Humans must get these fatty acids from dietary sources.
Linoleic acid (18:2), an essential fatty acid for humans,
is converted to arachidonic acid (20:4) which serves as a precursor
for the powerful hormone-like compounds called “eicosanoids”.
Eicosanoids serve normal functions in the body; however,
they are produced in excessive amounts in some disease states such
as arthritis.
Concentrations of eicosanoids in the body can be manipulated
by drugs (such as aspirin), by the type of fat in the diet, and
in some cases, by fat administered in a topical manner.
Because
there are no published scientific studies which have reported the
fatty acid composition of emu oil, a study was undertaken at Auburn
University to characterize the fatty acid composition of emu oil.
The results from this investigation help to explain the properties
and possible benefits of emu oil.
Ten samples
of emu fat/oil were analyzed by gas chromatography.
Two of these were rendered samples.
All but one sample was taken from the fat depot on the back
of the animal; the single sample was taken from the abdomen.
All samples were obtained from animals in the Southeastern
United States.
Results
indicated that emu oil is highest in monounsaturated fatty acids,
with lower amounts of saturated and polyunsaturated fatty acids
(Figure 1).
Oleic acid (18:1) was found to be the major monounsaturated
fatty acid in emu oil, comprising over 40% of the total fatty acids
(Figure 2).
Much smaller amounts (less than 5%) of the palmitoleic acid
(16:1) were found.
Major saturated
fatty acids in emu oil were palmitic acid (16:0) which comprised
approximately 20% of total fatty acids and stearic acid (18:0) at
8%.
Linoleic acid (18:2) at 20% of the total was the primary
polyunsaturated fatty acid were observed.
In
conclusion, approximately 70% of the fatty acids in emu fat are
unsaturated.
This composition is consistent with current recommendations
for a “heart healthy” diet.
The monounsaturated fatty acid, oleic acid, is the major
fatty acid in emu oil.
This fatty acid is a known enhancer for transport of bioactive
compounds into the skin, and thus, the fatty acid compositions consistent
with emu oil being very penetrating.
This aspect of the oil is being investigated in a second
phase of the project.
Editors Note: Emu oil research
dates back to 1987. However,
most studies have been proprietary.
No emu oil analysis has been reported in medical of scientific
journals.
The
AEA Research Committee sponsored this for public analysis.
The results will be published in Highlight of Agricultural
Research, an Auburn University publication, as well as scientific
journals.
Figure 1.
Figure
2.
*Highest
in monounsaturated fatty acids
*Lower
in saturated & polysaturated fatty acids
|