Chemistry of Natural Compounds, Vol. 43, No. 2, 2007
FLAVONOIDS FROM Calendula officinalis FLOWERS
V. A. Kurkin and O. V. Sharova
UDC 615.32:547.972+543.544
Medicinal calendula (Calendula officinalis L., Asteraceae) is widely cultivated in the Russian Federation and is used
to produce many medicines [1, 2].
The chemical composition of C. officinalis includes carotinoids (a leading group of biologically active compounds),
flavonoids, triterpene saponins, and several associated compounds [3, 4]. However, until now standardization of the raw
material and preparations of this plant has not been fully implemented.
In our opinion, this situation is to some extent due to contradictory literature data on the flavonoid composition of
medicinal calendula flowers.
Thus, one reference [5] lists the dominant component as rutin; another [6], isorhamnetin diglucoside. However, the
foreign literature [7] reports that calendula flowers contain isorhamnetin 3-O-rutinoside.
Considering the high flavonoid content in medicinal calendula flowers and their definite significance in determining
the biological activity of this material, it seemed advisable to study the component composition of calendula in order to justify
the standardization of flavonoids in this medicinal plant material.
We investigated flowers of medicinal calendula (Kal′ta variety, 2006) cultivated industrially at specialized facilities
in Samara District SGPU Sergievskii (Antonovka), ZAO Samaralektravy, and OOO Kentavr (Berezovka).
Ground air-dried flowers of medicinal calendula (Kal′ta variety) (100.0 g) were extracted exhaustively with ethanol
(
70%), combining for this maceration (24 h) and subsequent thermal extraction at 85-90°C. The aqueous ethanol extracts were
evaporated in vacuo to a thick residue (about 50 mL). The condensed extract was dried over silica gel (SG) L 40/100, eluted
with CHCl , and placed on a SG layer formed in CHCl . The column was eluted with CHCl and CHCl :C H OH in various
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proportions (97:3, 95:5, 93:7, 90:10, 88:12, 85:15, 80:20, 70:30).
Fractions with the dominant flavonoid were combined and placed on polyamide for further purification. Dry powder
extract + polyamide) was transferred to a chromatography column (10.0 g) (4.0 cm of sorbent, 5 cm diameter) with elution by
(
water and aqueous ethanol (20%, 40, 70, 96). The separation was monitored byTLC. The column purification over polyamide
produced 1 (the dominant diagnostic flavonoid).
The next set of fractions, which also contained flavonoid-type compounds, was combined, evaporated, and dried over
SG L 40/100 (1.0 g). The dry powder (extract + silica gel) was transferred to a chromatography column (4.0 cm of sorbent,
5
cm diameter). The column was eluted with CHCl containing various amounts of ethanol (5%, 10, 15, 20, 25, 30, 35) to
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produce yellow flavonoid 2, R 0.6.
f
Comparison of the chromatographic behavior of the dominant flavonoid with standard (GSO) rutin (R 0.4,
f
CHCl :CH OH:H O, 26:14:3) showed that the isolated compound had a different R value (about 0.5) and; therefore, was a
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different flavonoid.
Isolated flavonoids 1 and 2 were identified using UV, NMR, and mass spectrometry and chemical transformations.
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Compound 1, yellow crystals (EtOH), C H O , mp 173-175°C, [α]
+12.0° (c 0.83, water). UV spectrum
EtOH, λmax, nm): 257, 268 sh; +AlCl : 268, 276 sh, 359, 403. PMR spectrum [200 MHz, (CD ) CO + D O, δ, ppm, J/Hz]:
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D
(
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.04 (3H, d, J = 6.0, rhamnose CH ), 3.2-3.8 (10H, sugar part), 3.95 (3H, s, CH O), 4.50 (1H, d, J = 2.0, rhamnopyranose
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H-1′″), 5.23 (1H, d, J = 7.0, glucopyranose H-1″), 6.24 (1H, d, J = 2.0, H-6), 6.50 (1H, d, J = 2.0, H-8), 6.96 (1H, d, J = 2.0,
H-5′), 7.66 (1H, dd, J = 2.0 and 8.5, H-6′), 7.97 (1H, d, J = 2.0, H-2′).
Compound 2, yellowcrystals (EtOH), C H O , mp 227-229°C. UV spectrum (EtOH, λmax, nm): 257, 267 sh, 360;
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CH ONa: 272, 327, 410; +CH COONa: 272, 379; +CH COONa + H BO : 262, 377; +AlCl : 275, 412; AlCl + HCl: 270, 403.
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GOU VPO Samara State Medical Universityof Roszdrav, Russia, 443099, ul. Chapaevskaya, 89, fax +7-(846) 333 29
6, e-mail: vakur@samaramail.ru. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 179-180, March-April, 2007.
Original article submitted March 9, 2007.
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009-3130/07/4302-0216 2007 Springer Science+Business Media, Inc.
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