3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
P44 COMPARATIVE ExTRACTION METhODS OF
SOME bIOLOGIC ACTIVE COMPOuNDS IN
hERbS
AnDREEA IORDACHE, MOnICA CULEA and OnUC
COZAR
Babes-Bolyai University, Str. Kogalniceanu, nr.1, 3400 Cluj-
Napoca, Romania,
mculea@phys.ubbcluj.ro
Introduction
Many studies are made for the optimization of the experimental
design approach for obtaining the best recoveries,
low solvent consumption and reduced extraction times. In the
last years the number of procedures using extraction of organic
compounds from different matrices has increased 1,2 .
The aim of the present work is to present a comparison
between some extraction methods, for qualitative characterization
of flavors extracted from herb plants of different
sources.
Experimental
A liquid-liquid extraction method (LLE), compared with
two different solid-phase extraction methods (SPE- on 300 mg
RP-18, C-18 silica bonded and 300 mg TCS), a microwave
one (MWE) and an ultrasonic extraction one (USE) were
compared using an aroma compounds standard mixture. The
analytical method chosen were gas chromatography and gas
chromatography – mass spectrometry (GC-MS).
M a t e r i a l s a n d M e t h o d s
A Hewlett Packard GC 5890 couplet with a MS engine
5989B in the EI mode was used for compounds identification.
The GC was equipped with a HP-5MS capillary column
30 m × 0.25 mm diameter, 0,25 µm film thickness, in the temperature
program: 50 °C for 2 min, then increased to 250 °C
with a rate of 8 °C min –1 , helium flow rate 1 ml min –1 . Deactivation
by treating the injector glass liner with 5% dimethyldichlorosilane
in toluene was very important for a better sensitivity.
The GC/MS interface line and the ion source were
maintained to 200 °C, and quadrupol analyser at 100 °C.
Electron energy was 70 eV and electron emission 300 µA.
Methanol, methylen chloride, hexane, ethyl acetate, acetone
were purchased from Comchim (Bucharest, Romania).
The standards were from Fluka, Sueden: 1. 3-Hepten-2-one,
used as external standard (ES), 2. 1,8-cineol (eucalyptol) 3.
linalool 4. geraniol 5. alpha-terpinyl-acetate 6. geranyl acetate
7. amyl salicylate 8. myristic acid (C14 : 0) 9. palmitic acid
(C16: 0) 10. Stearic acid (C18 : 0) . FAME were from Polyscience
Corporation, Evantson, Illinois, USA. The standards,
100 µl each, formed the mixture M, except of the external
standard, 3-hepten-2-one, added separately before extraction.
Cartridges of 300 mg RP-18 and TSC were obtained from
Merck. A stock solution was obtained by diluting 100 µl of
each compound. Working standard was prepared by diluting
the stock solution to obtain a concentration of 3.3 % vol.
s667
L L e e x t r a c t i o n
A mixture of three solvents (S) was prepared: ethyl acetate:
hexane: methylen chloride (5 : 1 : 1, v/v/v). The LLE
extraction procedure was: 30 µl mixture M in 1 ml solution
distilled water: ethanol (1 : 1, v/v), or 1 ml hydroalcoholic
flavour extract), 1 ml distilled water and 0.33 ml solvent
S, (3 : 3 : 1, v/v/v) were mixed 1.5 minutes and then centrifugated
2 minutes. 1 µl 3-hepten-2-one, was added to the
supernatant and then 1 µl was injected two times by using the
autosampler injector.
S P E E x t r a c t i o n
The solid phase was conditioned with 3 ml methanol
and 3 ml distilled water. After sample application, washing
and drying 10 minutes at vacuum, the sample was eluted with
3 × 0.3 ml solvent. The solvent was solvent S in the case of
RP-18 cartridges and chloroform-acetone (1 : 1, v/v), in the
case of TSC cartridges. After adding of 1 µl of the external
standard to the eluate, 1 µl was injected by using the
autosampler injector. Each sample was injected twice.
M W e e x t r a c t i o n
The microwave extraction procedure was performed
at 2,45 GHz for 4 sec, to a temperature of 60 °C, in a screw
cap vessel. 30 µl mixture S was added to 1 ml hydroalcoholic
solution, 1 ml distilled water and 0.33 ml solvent S were placed
in the microwave funnel and extracted. Then 1 µl 3-hepten-2-one
(ES), was added to the supernatant and analyzed
twice.
U S E E x t r a c t i o n
The ultrasonic extraction procedure was performed
1min, at a temperature of 60 °C. The ultrasonic probe was
placed in the vessel containing 30 µl mixture S in 1 ml hydroalcoholic
solution, 1 ml distilled water and 0.33 ml solvent
S. After extraction, 1 µl 3-hepten-2-one (ES) was added to
the supernatant and analyzed.
Table I
Recovery [%] obtained by different procedures
Component LLE SPE SPE MW US
heptenone
1,8-cineole
(eucalyptol)
98.97 81.47 68.54 100.84 99.75
linalool 96.67 86.96 72.07 100.98 100.50
geraniol 94.31 87.54 77.91 111.48 112.12
alfa-terpenyl
acetate
97.57 86.13 73.52 102.26 100.37
geranyl
acetate
96.28 83.14 72.75 102.57 99.86
amyl
slicilate
97.23 85.72 73.99 120.91 118.03
C14 : 0 100.82 86.24 75.07 98.02 95.04
C16 : 0 97.14 86.73 75.87 96.91 92.95
C18 : 0 96.93 85.54 74.68 95.74 92.07