Chemistry of Natural Compounds, Vol. 48, No. 3, July, 2012 [Russian original No. 3, May–June, 2012]
COMPONENTS AND ANTIOXIDANT ACTIVITY OF THE POLAR
EXTRACTS OF Chrysanthemum trifurcatum
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H. Mokaddem-Daroui, O. Touafek, A. Kabouche,
UDC 547.972
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Z. Kabouche, C. A. Calliste, and J. L. Duroux
The Chrysanthemum genus (Asteraceae) includes nearly 200 species of which 15 are distributed in Algeria [1, 2].
This genus is known to contain flavonoids and terpenoids, which are responsible for various activities, e.g., antimicrobial,
antitumor, antiviral, anti-inflammatory, antioxidant, and hepatoprotective [3–8].
The species Chrysanthemum trifurcatum, endemic to the Septentrional Sahara [1], has not been the subject of any
phytochemical study. This plant, named “gartoufa,” is traditionally used to treat constipation and hepatic desorders [9]. It is
also locally used in food such as “chorba” and “couscous.”
Aerial parts of Chrysanthemum trifurcatum were collected during the flowering period in March 2008, at Ghardaia.
A voucher specimen was deposited at the Herbarium of the Laboratory under the code number LOST.Ct.04.08.
Air-dried and powdered aerial parts (1 kg) of Chrysanthemum trifurcatum were macerated in a methanolic solution
(70%). The extract was successively concentrated to dryness (under low pressure); the residue was dissolved in boiling water
and extracted with petroleum ether, dichloromethane, ethyl acetate, and n-butanol, successively.
TLC tests showed the similarity of both the EtOAc and n-BuOH extracts.
The butanolic extract (15 g) was subjected to column chromatography on polyamid SC6 with a gradient of toluene–MeOH
of increasing polarity. The major fraction was treated with preparative TLC on polyamid DC6 using the system
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toluene–MeOH–methylethylketone (4:3:3), leading to six compounds (1–6) which were identified by the use of H NMR and
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C NMR, DEPT, and high-technique experiments, COSY, HMQC, and HMBC, in addition to UV spectroscopy.
Compound 1, identified as caffeic acid [10].
Compound 2, identified as apigenin [10–12].
Compound 3, identified as luteolin [10–12].
Compound 4, identified as apigenin 7-glucoside [10–12].
Compound 5, identified as luteolin 7-glucoside [10–12].
Compound 6, identified as quercetin [10–12].
Flavonoids 2–6 have already been isolated from Chrysanthemum genus while caffeic acid (1) is reported for the first
time from the genus.
Acid Hydrolysis.The pure compounds 4 and 6 were treated with 2 M HCl at 100ꢀC for 1 h.
The hydrolysates were extracted with EtOAc, and the aglycones were identified by their UV spectra in methanol and
by comparison of their R with authentic samples. Sugars were identified in the aqueous residue by comparison with authentic
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samples on silica gel TLC impregnated with 0.2 M NaH PO , solvent Me CO–H O (9:1), and revealed with aniline malonate.
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Antioxidant Activity. The antioxidant activity of the butanolic extract of Chrysanthemum trifurcatum (BECT) was
assessed on the basis of the scavenging activity of the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH, from Sigma) free radical
[13] using electron spin resonance (ESR) [14]. The reaction mixtures contained 100 mL test samples and 100 mL DPPH
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ethanolic solution (5 ꢁ 10 M). The inhibition ratio was determined by comparison with a water-treated control group. ESR
spectra were obtained with a Bruker ESP300E spectrometer using micro-sampling pipettes at room temperature under the
following conditions: modulation frequency, 100 kHz; modulation amplitude, 0.197 mT; scanning field, 349.7 mT; receiver
1) Universite Mentouri-Constantine, Departement de Chimie, Laboratoire d'Obtention de Substances Therapeutiques,
25000, Constantine, Algeria, e-mail: ahkabouche@yahoo.fr; 2) Laboratoire de Biophysique, UPRES EA-1085, Biomolecules
et Cibles Cellulaires Tumorales Faculte de Pharmacie, 2 rue du Dr. Marcland, 87025, Limoges Cedex, France. Published in
Khimiya Prirodnykh Soedinenii, No. 3, May–June, 2012, pp. 446–447. Original article submitted August 28, 2010.
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0009-3130/12/4803-0498 02012 Springer Science+Business Media, Inc.