ISSN 10214437, Russian Journal of Plant Physiology, 2012, Vol. 59, No. 3, pp. 326–332. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © R.A. Sidorov, A.V. Zhukov, A.G. Vereshchagin, V.D. Tsydendambaev, 2012, published in Fiziologiya Rastenii, 2012, Vol. 59, No. 3, pp. 362–368.
While investigating neutral lipid composition of the
mature oilbearing fruits of several euonymus species,
we found them to contain an unidentified component
(“X component”). Under the conditions of TLC on
silica gel in the
hexanediethyl ether system, the X
component band coincided in its
value with that of
the standard fatty acid methyl esters (FAMEs). Ear
lier, FAMEs of natural origin were sometimes found in
higher plants [1, 2], and therefore we have originally
supposed that the X component also consists of
FAMEs. To test this suggestion, we analyzed its com
position using capillary GCMS techniques. It turned
out, however, that the X component contained not
only FAMEs but also the FA esters of ethyl (FAEEs)
and some other lower alcohols, thus representing a
mixture of FA loweralkyl esters (FALAEs). The com
position of these FALAEs in four euonymus species
fruits was determined in this study.
MATERIALS AND METHODS
Mature fruits of
, as well as maturing
(at the 39th day after the onset of flowering)
fruits, were collected during 2009
and 2010 in the arboretum of the Main Botanical Gar
den of RAS and stored at
. A sample of fruits
(ca. 10 g) was fixed for 1 min in boiling water and sep
arated into watersaturated arils (flesh) and seeds.
Both parts of the fruit were homogenized in an equal
amount of water. Neutral lipids were extracted from the
aqueous homogenate with chloroform, which was previ
ously washed with water to remove any shortchain alco
hols, and stored as a benzene solution at
After removing benzene
, the lipids were
dissolved in hexane, and the solution was transferred
on 22 cm
25 mm glass column containing 10 g of
neutral alumina for chromatography (L 40/250, Che
mapol, Czech Republic). The column was first washed
with hexane (70 mL), and this eluate was discarded.
The next hexane fraction (ca. 200 mL) was collected.
As judged from analytical TLC in a hexane–ethyl
ether system (9 : 1, v/v), the X component was entirely
concentrated in this fraction. A TLCpure preparation
of this component was obtained by preparative TLC
Occurrence of Fatty Acid LowerAlkyl Esters
in Euonymus Fruits
R. A. Sidorov, A. V. Zhukov, A. G. Vereshchagin, and V. D. Tsydendambaev
Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya ul. 35, Moscow, 127276 Russia;
fax: 7 (499) 9778018; email: email@example.com
Received June 21, 2011
—Small amounts of a mixture of fatty acid loweralkyl esters (FALAEs) were obtained from chloro
form extracts of the fruit arils and seeds of four euonymus species (
sp., Celastraceae). The FALAEs
were the products of biosyntheses in the cell rather than experimental artifacts. By using GCMS, this mix
ture was shown to contain a total of 19 individual FALAE species comprising four separate fractions, viz.
methyl (FAMEs), ethyl (FAEEs),
butyl FA esters. Fruit FALAEs included mainly FAEEs
and, to a lesser extent, FAMEs, while the
butyl FA esters, which occurred less frequently, were
found here for the first time as the plant products. The FALAE acid components included C
mono, di, and trienoic FAs with the predominance of ubiquitous linoleic, oleic, palmitic, and, in some
linolenic acid. The indices of qualitative and quantitative composition of separate FALAE frac
tions varied considerably depending on the plant species, fruit part (aril or seed), and the extent of fruit matu
rity. It can be supposed that, in some euonymus species, FAMEs and FAEEs are formed at the expense of the
same FA pool characteristic for a given species. As a whole, euonymus FALAEs and triacylglycerols seem to
be synthesized from different FA pools. Discussed is the physiological significance of FALAE biosynthesis in
plant metabolism, possible pathways of this biosynthesis, as well as the perspectives of further investigations
of FALAEs of plant origin.
sp., fruits, seeds, arils, FALAEs, FAEEs, FAMEs, fatty acids, biosynthesis.
: amu—atomic mass unit; FAEEs—FA ethyl esters;
FAMEs—FA methyl esters; FALAEs—FA loweralkyl esters;
m—carbon atom number in the aliphatic chain; TAGs—triacylg
lycerols; UI—FA unsaturation index.