ESSENTIAL OIL COMPOSITION OF C. BONARIENSIS 39
Copyright © 2004 John Wiley & Sons, Ltd. Flavour Fragr. J. 2005; 20: 39–41
FLAVOUR AND FRAGRANCE JOURNAL
Flavour Fragr. J. 2005; 20: 39–41
Published online 27 October 2004 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/ffj.1392
Essential oil composition from some plant parts of
Conyza bonariensis (L.) Cronquist
Luiz C. A. Barbosa,
1
* Vanderlúcia F. Paula,
2
Anelisa S. Azevedo,
3
Eldo A. M. Silva
3
and
Evandro A. Nascimento
4
1
Laboratório de Análise e Síntese de Agroquímicos (LASA), Departamento de Química, Universidade Federal de Viçosa, 36571-
000 Viçosa, MG, Brazil
2
Departamento de Química e Exatas, Univ. Est. do Sudoeste da Bahia, 45200-000 Jequié, BA, Brazil
3
Departamento de Botânica, Universidade Federal de Viçosa, 36571-000 Viçosa, MG, Brazil
4
Instituto de Química, Universidade Federal de Uberlândia, 38401-136 Uberlândia, MG, Brazil
Received 23 April 2003; Revised 28 October 2003; Accepted 16 November 2003
ABSTRACT: The essential oils from the roots, leaves, stems and inflorescences of Conyza bonariensis L. were invest-
igated. A total of 17 constituents were identified by GC-MS, including monoterpenes, acetylenes, sesquiterpenes and
diterpenes. The major constituents were matricaria methyl ester (roots, 74.4%), limonene (leaves, 29.6%), manool (stems,
25.3%) and carvone (inflorescences, 21.1%). Copyright © 2004 John Wiley & Sons, Ltd.
KEY WORDS: Conyza bonariensis; Asteraceae; essential oil composition; acetylenes; limonene; carvone; matricaria methyl
ester; manool
* Correspondence to: L. C. A. Barbosa, Laboratório de Análise e Sntese de
Agroquímicos (LASA), Departamento de Química, Universidade Federal de
Viçosa, 36571-000 Viçosa, MG, Brazil.
E-mail: lcab@ufv.br
Contract/grant sponsor: Brazilian Research Council (CNP
q
).
Introduction
Conyza bonariensis (L.) Cronquist (Asteraceae) is a
plant currently known in Brazil as buva, voadeira,
margaridinha-do-campo, rabo-de-foguete, arnicão, lagar-
teira, capiçoba, acatóia amongst others.
1,2
An infusion
from its aerial parts is used in popular medicine as anti-
septic, hemostatic and antispamodic.
3–5
The essential
oil of some Conyza species have been investigated;
6–9
however, we found only one report about the essential oil
composition of Conyza bonariensis.
2
In the present work
we report the first study of the essential oil composition
of individual parts (root, stem, leaf and inflorescence) for
this plant.
Experimental
Plant material and essential oil isolation
Seeds of Conyza bonariensis were collected from speci-
mens found at the Campus of Federal University of
Viçosa, Minas Gerais State (Brazil), in November 1997.
The seeds were cultivated in a greenhouse, in 40 pots of
10 l each, from February 1998 until the plants were in
full bloom. At this stage, 40 plants were collected and
separated into roots, stems, leaves and inflorescences.
The leaves and inflorescences were dried for 3 days and
the roots and stems for 5 days, at 28 ± 1 °C. For each
extraction 15 g of material was used. The essential oil
was steam distilled using a Clevenger-type apparatus
for 90 min. The resulting mixture of oil and water
was collected (90 ml) and the oil extracted with pentane
(3 × 30 ml). The organic solvent was evaporated under
reduced pressure. The obtained oil was weighed and
the yield calculated. All of the steam distillations were
carried out in four replicates.
Analysis of the essential oils
The oils were analyzed previously by gas chromato-
graphy, using a Shimadzu GC 17-A equipped with
a flame ionization detector (FID), and later, by gas
chromatography–mass spectrometry (GC-MS) using a
Shimadzu QP 5000 equipment. The chromatographic
conditions were the same in both analyses: fused silica
capillary column (30 m × 0.25 mm) with a DB-5 bonded
phase (0.25 μm film thickness), injector temperature
220 °C; detector (or interface) temperature 240 °C; col-
umn program, 60–240 °C at 3 °C min
-1
, 240 °C for
15 min; carrier gas He (1 ml/min); the injection volume
was 1.0 μl (1% solution in dichloromethane). The MS
data were recorded at 70 eV, in the range 45–450 amu.
Each component was identified by comparison of its
mass spectra with those available from the equipment
database (Wiley 140) and from the literature
10,11
and also
by its retention index. Kovat’s retention index (KI) was
determined using a calibration curve of n-alkanes.
Infrared spectra were recorded as a thin film on a
Perkin Elmer FTIR Paragon 1000 Spectrophotometer.