[P-075]
VOLATILE COMPOUNDS OF TWO MEMBERS OF Inula verbascifolia GROUP:
I. verbascifolia subsp. parnassica AND I. verbascifolia subsp. methanea

Olga TZAKOU1, Alexandra PETROPOULOU1,
Theophanis CONSTANTINIDIS2 and Catherine HARVALA1
1Department of Pharmacognosy, School of Pharmacy, University of Athens, Athens 15771, Greece
2Institute of Botany, Department of Biology, University of Patras, Gr-26500, Patras

ABSTRACT

Hydrodistilled oils from aerial parts of two Greek Inula species (I. verbascifolia subsp. parnassica and I. verbascifolia subsp. methanea) were subjected to GC/MS analyses. More than 90 compounds were identified from the oils. The major oil constituents were found to be methyl salicylate (23.4%) and cis-chrysanthenol (17.3%) for I. verbascifolia subsp. parnassica. The oil of I. verbascifolia subsp. methanea was made up mainly of sesquiterpenoids of which epi-a-cadinol (19.5%) and (Z)-nuciferol (16.6%) were the main constituents.


INTRODUCTION

The genus Inula, from the tribe Inulae, has often been chemically investigated. Sesquiterpene lactones and flavonoids are typical in the genus (Harborne 1977).

The chemical composition of the oils of some Inula species, especially I. helenium have been investigated [Perez-Alonso et al. (1996), Bourrel et al. (1993)].

Our present contribution deals with the volatile compounds of two Greek endemic taxa: I. verbascifolia subsp. parnassica (Boiss. & Heldr.) Tutin (= I. parnassica Boiss. & Heldr.) and I. verbascifolia subsp. methanea (Hausskn.) Tutin (= I. methanea Hausskn.).

Both taxa are distributed in Peloponnisos and Sterea Ellas, while I. verbascifolia subsp. parnassica is also found on the island of Evia. The main morphological characters that are used to distinguish between them include leaf indumentum, number and shape of upper bracts and involucral bracts and also, size of ligules (Ball and Tutin 1976).


MATERIALS AND METHODS

Plant material

Wild growing Inula verbascifolia plants were collected during anthesis. Specimens were identified by Dr.Th.Constantinidis. Voucher specimens have been deposited at the Herbarium of the Institut of Botany, University of Patras (UPA).

Inula verbascifolia subsp. parnassica : A= Mt. Parnassos, County Biotia, 1100 m (July 1999).

Inula verbascifolia subsp. methanea: B= Mt. Parnes, County Attiki, 800 m (June 1998).

Sample Analysis

Dried aerial parts from each population were cut into small pieces just before subjected to hydrodistillation for 3h using a Clevenger-type apparatus. Yields were 0.25% (v/w) for I. verbascifolia subsp. parnassica and 0.16% (v/w) for I. verbascifolia subsp. methanea.

The oils were analyised by GC/MS using a Hewlett Packard 6890/5973 system operating in EI mode, fitted with a HP-5MS capillary column. GC oven initial temperature was 60°C and programmed to 280°C at a rate of 3°C/min. Library search was carried out using Wiley, NIST/NBS MS libraries and from the best match of their mass spectra with those of the literature (Adams 1995).


RESULTS AND DISCUSSION

The list of constituents identified in the aerial parts of I. verbascifolia subsp. parnassica and I. verbascifolia subsp. methanea is shown in Table 1. The results show that there are interesting differences in the composition among the subspecies studied. These dissimilarities can be of high chemotaxonomic importance.

The oil of I. verbascifolia subsp. parnassica was characterized by the presence of high concentration of esters, with methyl salicylate being the major component (23.4%). Oxygenated sesquiterpenes constitued only 3.3% of the oil. In the sesquiterpene hydrocarbons fraction the main component was (E)-caryophyllene (13.2%). cis-Chrysanthenol (17.3%) and linalool (7.1%) were the monoterpenes which were present in appreciable amounts.

In the oil of I. verbascifolia subsp. methanea linalool (21.2%), epi-a-cadinol (19.5%) and (Z)-nuciferol (16.6%) were the major representatives of monoterpenes the first and sesquiterpenes the others. In esters fraction the main component was (Z)-3-hexenyl benzoate (6.4%).


Table 1. Percentage composition of the oils of Inula verbascifolia subsp. parnassica
and I. verbascifolia subsp. Methanea
Components
KI
Sample A
Sample B
(E,E)-2,4-heptadienal
988
t
-
p-cymene
1011
-
t
limonene
1015
-
t
1,8-cineole
1018
-
t
Benzene acetaldehyde
1029
t
0.7
(E)-b-ocimene
1033
-
t
g-terpinene
1044
t
-
(Z)-linalool oxide
1058
-
t
(E)-linalool oxide
1073
-
0.7
terpinolene
1078
t
-
linalool
1088
7.1
21.2
nonanal
1091
1.2
0.5
p-menth-3-en-8-ol
1134
t
-
(Z)-2-nonenal
1145
t
-
chrysanthenol
1149
17.3
-
ethyl benzoate
1156
t
-
terpin-4-ol
1163
0.9
-
octanoic acid
1170
t
-
a-terpineol
1175
t
1.9
methyl salicylate
1178
23.4
t
dodecane
1185
t
-
decanal
1191
1.1
0.8
b-cyclocitral
1205
t
t
nerol
1213
-
t
cis-3-hexenyl-2-methyl butyrate
1220
-
t
neral
1224
-
t
geraniol
1238
t
1.8
geranial
1244
-
t
nonanoic acid
1257
-
t
thymol
1276
-
 
(E,Z)-2,4 decadienal
1277
t
t
carvacrol
1288
-
t
undecanal
1290
1.2
-
(E,E)-2,4-decadienal
1299
t
t
(Z)-3-hexenyl tiglate
1307
t
-
butyl benzoate
1310
2.5
-
hexyl tiglate
1314
t
-
(Z)-3-hexenyl hexanoate
1323
-
t
(Z)-methylpropyl octanoate
1331
t
-
eugenol
1339
t
t
2-dodecen-1-al
1346
t
t
cyclosativene
1348
t
t
decanoic acid
1355
t
t
a-copaene
1358
t
t
(E)- b-damascenone
1367
2.1
t
(E,Z)-nepetalactone
1370
-
t
(E)-jasmanone
1374
-
t
(Z)-jasmanone
1381
t
t
iso-italicene
1385
-
t
methyl eugenol
1388
t
t
dodecanal
1392
1.0
-
(E)-b-damascone
1396
-
t
(E)-caryophyllene
1400
13.2
t
b-gurjunene
1411
t
-
2-methyl butyl benzoate
1420
t
-
aromadendrene
1426
t
-
geranyl acetone
1435
-
t
a-humulene
1435
1.9
0.8
allo-aromadendrene
1442
t
1.6
a-acoradiene
1448
-
t
g-gurjunene 
1455
-
t
g-muurolene
1458
t
t
g-curcumene
1462
-
1.3
germacrene D
1463
3.8
-
ar-curcumene
1465
-
1.3
(E)-b-ionone
1468
4.4
t
epi-cubebol
1476
-
t
bicyclogermacrene
1478
0.9
-
a-muurolene
1482
t
t
tridecanal
1494
5.3
-
g-cadinene
1495
t
2.5
d-cadinene
1504
2.6
2.9
a-calacorene
1524
t
t
(E)-nerolidol
1547
t
-
(Z)-3-hexenyl benzoate
1552
4.4
6.4
Germacrene D-4-ol
1556
t
-
Hexyl benzoate
1558
2.4
t
caryophyllene oxide
1563
3.3
2.8
guaiol
1581
-
2.6
10-epi-g-eudesmol
1599
-
t
a-acorenol
1607
-
t
g-eudesmol
1611
-
t
epi-a-cadinol
1624
-
19.5
hinesol
1625
-
t
epi-a-muurolol
1626
t
-
a-muurolol
1632
t
9.4
b-eudesmol
1636
t
-
a-cadinol
1640
t
4.7
14-hydroxy-9-epi-(E)-caryophyllene
1673
t
-
(Z)-nuciferol
1711
-
16.6
(E)-nuciferol
1734
-
t
benzyl benzoate
1747
t
t
tetradecanoic acid
1749
t
-
pentacosane
2500
t
-
Total  
100
100
t=trace<0.01%

LITERATURE
  1. Adams R.P.(1995): Identification of Essential Oil Components by Gas Chromatography and Mass Spectrometry, Allured Publ. Corp., Carol Stream, IL, USA.

  2. Ball P.W. and Tutin T.G. (1976): Inula L. In: Flora Europaea. Edits., Tutin T.G., Heywood V.H., Burges N.A., Moore D.M., Valentine D.H., Walters S.M. and Webb D.A., vol. 4. pp 133-136, Cambridge University Press, Cambridge.

  3. Bourrel C., Vilarem G. and Perineau F. (1993): Chemical analysis, bacteriostatic and fungistatic properties of the essential oil of Elecampane (Inula helenium L.), J.Essent.Oil Res., 5, 411-417.

  4. Harborne J.B.(1977): In: The Biology and Chemistry of the Compositae. Edits., Heywood V.H.,. Harborne J.B and Turner B.L., p. 603, Academic Press, London.

  5. Perez-Alonso M.J., Velasco-Negueruela A., Duru M.E., Harmandar M. and Garcia Vallejo M.C. (1996): Composition of volatile oil from the aerial parts of Inula viscosa (L.) Aiton., Flav. Fragr. J., 11, 349-351.

[P-075]