3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
P42 GAS ChROMATOGRAPhy-MASS
SPECTROMETRy ChARACTERIZATION OF
SEA buCKThORN
AnDREEA IORDACHE, RADU MInEA, MOnICA
CULEA and CAMELIA LEHEnE
Babes-Bolyai University, Str. Kogalniceanu, nr.1, 3400 Cluj-
Napoca, Romania,
mculea@phys.ubbcluj.ro
Introduction
Besides naturally growing plants, sea buckthorn (Hippophae
rhamnoides) hybrids of different subspecies are cultivated
in order to prevent desertification, since it forms strong
root and it is resistant to extreme temperature, drought and
poor soil. There is a long tradition in Asia for using sea buckthorn
berries in folk medicine. It was demonstrated that the
oils extracted from pulp and seeds have regenerating, antiinflammatory,
anti-ulcerogenic, hepatoprotective, cytoprotective
properties. 1–4 Sea buckthorn berries are exceptionally
rich in both lipophilic and hydrophilic bioactive compounds
and represent an important resource for pharmacy and food
industry. The pulp oil has a special composition with a very
high content of unusual palmitoleic acid, up to 54 % of total
fatty acids, while the seeds oil is rich in linoleic and α-linolenic
acids. Other important compounds of sea buckthorn oil
are sterols, tocopherols and tocotrienols and their content
depend on the berries origin, growth condition and oil processing
method.
The aim of this study was to develop a sensitive analytical
method for determination of fatty acids, vitamin F and
E and sterols in sea buckthorn oil, by gas chromatography/
mass spectrometry (GC/MS). The method was applied for
testing the lipophilic compounds after the treatment at different
kGy doses with accelerated electrons.
Experimental
M a t e r i a l s a n d M e t h o d s
Standards of fatty acids methyl esters and acetyl chloride
were from Fluka (Buchs, Switzerland), α-tocopherol
standard was from Sigma-Aldrich (Munich, Germany). All
other chemicals were from Comchim (Bucharest). The oil
and plant samples were from Hofigal (Bucuresti).
G C - M S a n d H P L C
A Trace DSQ ThermoFinnigan quadrupol mass spectrometer
coupled with a Trace GC was used. The methyl esthers
of the fatty acids were separated on a Rtx-5MS capillary
column, 30 m × 0.25 mm, 0.25 µm film thickness, using
a temperature program from 50 °C (1 min) to 310 °C, at
8 °C min –1 ; then kept 8 minutes at 310 °C. The conditions
used for GC-MS were: transfer line temperature 250 °C,
injector temperature 200 °C; ion source temperature 250 °C;
Splitter: 10 : 1. Electron energy was 70 eV and emission current,
100 µA.
s663
E x t r a c t i o n a n d D e r i v a t i z a t i o n
Fatty acid methyl esters (FAME) were obtained by esterification
reaction of known quantities of oil with 100 µl 3M
HCl methanol at 100 °C for 60 min followed by evaporation
to dryness under n 2 stream 0.1 mg of the internal standard
C11 : 1 was added at 20 µl oil. Then the sample was solved
in 100 µl DCM or ethyl acetate, and 3 µl were injected into
GC-MS. Vitamin E and sterols were also determined in the
different samples.
Fig. 1. FAME, vitamin E and sterols separation in sea buckthorn
oil
H P L C A n a l y s i s o f α - t o c o p h e r o l
The sea buckthorn oil samples were injected into HPLC
for vitamin E determination. The sea buckthorn oil was saponified
with 60% KOH in ethanol, in the presence of ethanol
and pyrogallol, at 75 °C for 45 min. The sample mixture
Table I
The compounds identified in sea buckthorn oil
Compounds RT [min] area [%]
Methyl myristate (C14 : 0) 19.85 0.79
methyl palmitoleate(C16 : 1) 22.36 30.68
methyl palmitate(C16 : 0) 22.63 24.53
methyl oleate +linoleat
(C18 : 1 + C18 : 2)
24.73 37.18
methyl stearate (C18 : 0) 24.89 0.63
C20 : 1 26.83 0.55
methyl arachinate (C20 : 0) 27.01 0.3
C22 : 1 28.93 0.86
behenic acid methyl ester (C22 : 0) 29.03 0.22
C24 : 1 30.57 0.41
methyl lignocerate (C24 : 0) 30.89 0.14
C26 : 0 32.31 0.26
vitamin E 34.47 0.6
sitosterol 36.36 2.13
lupeol 37.41 0.42
urs-12-en-28-ol 40.8 0.31