Vol.3, No.2, 104-108 (2011) Natural Science
Copyright © 2011 SciRes. OPEN ACCESS
Chemical compositions of the essential oil and
calculation the biophysicochemical coefficients of the
components of Hymenocrater longiflorus Benth. of Iran
Avat (Arman) Taherpour1*, Hossein Maroofi2, Mahdi Changizi3, Reza Vafaei Shoushtari3,
Kambiz Larijani4, Azadeh Kazempour1
1Chemistry Department, Graduate School, Islamic Azad University, Arak Branch, Arak, Iran; *Corresponding Author:
avatarman.taherpour@gmail.com, a.taherpour@iau-arak.ac.ir
2Research Center of Agriculture & Natural Resources, Forked Road of Jame-Jam, Sanandaj, Iran
3Faculty of Agriculture, Islamic Azad University, Arak Branch, Arak, Iran
4Research Council of Science and Research Campus, Islamic Azad University, Tehran, Iran
Received 8 December 2010; revised 10 January 2011; accepted 12 January 2011.
The volatile constituents of the essential oil of
Hymenocrater longiflorus Benth. growing wild
in Kurdistan-Iran were investigated using the
GC and GC/MS techniques. Fifteen compounds,
representing twenty (97.03%) of the total oil
were identified. The main components were: α-
Pinene (22.47%), β-Caryophyllene (18.05%), β-
Eudesmol (14.92%), α-Copaene (9.84%), γ-Ele-
mene (6.79%), δ-Cadine-ne (6.13%), (–)Bornyl
acetate (5.61%), α-Amorphene (3.84%), α-Fen-
chyl acetate (2.35%) and β-Pinene (2.07%).
Some of the physicochemical properties like the
logarithm of calculated Octanol-Water parti-
tioning coefficients (log Kow), total biodegrada-
tion and (TBd in mol/h and gr./h), water solubility
(Sw, mg.L-1 at 25ºC) and median lethal concen-
tration 50 (LC50) were calculated for the 15 com-
ponents of Hymenocrater longiflorus Benth.
Keywords: Hymenocrater longiflorus Benth.;
Essential Oil Compounds; Hydro Distillation;
α-Pinene; β-Caryophyllene; β-Eudesmol;
α-Copaene; Octanol-Water Partitioning; Total
Biodegradation; LC50; Gas Chromatography; Mass
Hymenocrater genus has over 21 species in the world.
[1,2] The Hymenocrater longiflorus Benth. materials of
this study were collected from west of Iran (from the
mountains area, altitude 1550-1800 m, in front of the
Dezlie village-Marivan-Kurdistan province of Iran) at the
Jun. 2008. A voucher specicum has been deposited in
herbarium of Research Center of Agriculture & Natural
Resources, Sanandaj-Kurdistan, Iran (Herbarium ID:
This herb was firstly nominated by G. Bentham in
1848. The local name of Hymenocrater longiflorus
Benth., is Soor-Halale (Sỏỏr-HΛLΛLΕ). The other names
of this herb are: Gole Arvaneh-Avarmani and SoorSan-
duo. The Hymenocrater longiflorus Benth. was utilized
as a medicinal herb in local and traditional medicine (in
Kurdistan). From the aerial parts of this herb in crude or
baked form was utilized as an anti-inflammatory, seda-
tive, anti-skin allergic reaction (for skin diseases and
insect bite) by folks in local medicine.
The octanol-water partition coefficient (Kow) is a meas-
ure of the equilibrium concentration of a compound be-
tween octanol and water that indicates the potential for
partitioning in to soil organic matter (i.e., a high Kow in-
dicates a compound which will preferentially partition
into soil organic matter rather than water). This coeffi-
cient is inversely related to the solubility of a compound
in water. The log Kow is used in models to estimate plant
and soil invertebrate bioaccumulation factors. This pa-
rameter is also used in many environmental studies to
help determine the environmental fate of chemicals [3-5].
Biodegradation is usually quantified by incubating a
chemical compound in presence of a degrader, and meas-
uring some factors like oxygen or production of CO2.
The biodegradation studies demonstrate that microbial
biosensors are a viable alternative means of reporting on
potential biotransformation. However, a few chemicals
are tested and large data sets for different chemicals need
for quantitative structural relationship studies [6].
An LC50 value is the concentration of a material in air
A. Taherpour et al. / Natural Science 3 (2011) 104-108
Copyright © 2011 SciRes. OPEN ACCESS
that will kill 50% of the test subjects (animals, typically
mice or rats) when administered as a single exposure
(typically 1 or 4 hours). Also called the median lethal
concentration and lethal concentration 50, this value
gives an idea of the relative acute toxicity of an in hal-
able material. Typical units for LC50 values are parts per
million (ppm) of material in air, μg (micrograms, 10-6
gram) per liter of air and milligrams (10-3 gram) per cu-
bic meter of air [7].
Dried aerial parts of Hymenocrater longiflorus Benth.
were subjected to hydrodistillation for 5 hours using
Clevenger-type apparatus to produce a yellow oil in 0.28%
(w/w) yield. The essential oil of the aerial parts of Hy-
menocrater longiflorus Benth. was examined by GC/MS
(GC: HP 6890, MS: HP 5973), column (HP5-MS, 30 m
0.25 mm fused silica capillary column, film thickness
0.32 m) by temperature program 60C (3 min)-210C
(2 min) at the rate of 6C/min (injection temperature
250C, carrier gas: helium (with purity 99.999%), de-
tector temperature 150C, ionization energy in mass was
70 eV, mass range 10-300 amu, and scan time was 1 sec.
The list of identified components is presented in Ta-
ble 1. The constituents were identified by comparing
their MS spectra with those in computer library or with
authentic compounds. The identifications were confirm-
ed by comparison of their retention indices either with
those of authentic compounds or with data in the litera-
ture [8-10]. In the aerial parts of Hymenocrater longi-
florus Benth. the major identified components and the
relative amounts based on peak area were: α-Pinene
(22.47%), β-Caryophyllene (18.05%), β-Eudesmol
(14.92%), α-Copaene (9.84%), γ-Elemene (6.79%), δ-
Cadinene (6.13%), (–) Bornyl acetate (5.61%), α-
Amorphene (3.84%), α-Fenchyl acetate (2.35%) and β-
Pinene (2.07%).
The calculated data of the Octanol-Water partitioning
coefficients (log Kow) and the total biodegradation TBd
(in mol/h and gr/h), water solubility (Sw, mg.L-1 at 25ºC)
and median lethal concentration 50 (LC50) were calcu-
lated by the EPI-suit v4.00 package [11].
Some of the plants from genus Hymenocrater have
been previously studied, but there are rare studies of the
chemical composition of essential oil of plants from ge-
nus Hymenocrater. This study elaborates upon the vola-
tile constituents of the essential oil of Hymenocrater
longiflorus Benth. growing wild in Kurdistan-Iran were
investigated by GC and GC/MS technique. As could see
in Table 1, α-Pinene (22.47%), β-Caryophyllene (18.05%)
(trans-Caryophyllene) and β-Eudesmol (14.92%) have
the high percentages (about 55.44%) among the fifteen
components that were identified. Some other compo-
nents, i.e. α-Copaene (9.84%), γ-Elemene (6.79%), δ-
Table 1. Essential oil constituents, logarithm of calculated Octanol-Water partitioning coefficients (logKow), total biodegradation and
(TBd in mol/h and gr./h), water solubility at 25ºC (mg/L) and median lethal concentration 50 (LC50) of Hymenocrater longiflorus
Benth. of Iran.
Total Biodegradation
No Name of
Compound K. I.* RT** % logKow aWater Solubility
at 25ºC (mg/L)
LC50 (in mg/L
or ppm) mol/h × 10–5 gr./h × 10–2
1 α-Pinene 923 5.42 22.474.27
(4.44)a 4.071 1.928 7.70 1.05
2 β-Pinene 962 6.38 2.07
(4.16)a 7.061 1.642 6.00 0.81
3 α-Fenchyl acetate 1136 10.79 2.35 3.86 23.230 6.322 13.00 2.64
4 (–)Bornyl acetate 1236 13.21 5.61 3.86
(4.30)a 42.514 2.316 22.00 4.28
5 γ-Elemene 1243 13.37 6.79 7.09 0.575 0.005 18.00 3.71
6 α-Copaene 1314 14.96 9.84 5.71 0.161 0.086 12.00 2.47
7 trans-Caryophyllene 1351 15.81 18.051.54 302.6 40.5874 7.80 0.94
8 Valencene 1366 16.16 1.81 6.30 0.543 0.026 13.00 2.56
9 α-Humulene 1378 16.44 1.15 6.95 0.014 0.013 15.00 3.13
10 α-Amorphene 1394 16.81 3.84 6.19 0.512 0.033 11.00 2.30
11 β-Maaliene 1411 17.18 1.14 6.21 0.067 0.031 17.00 3.41
12 Germacrene-D 1426 17.50 0.85 6.99 0.819 0.006 18.00 3.68
13 δ-Cadinene 1433 17.63 6.13 6.32 0.808 0.025 12.00 2.38
14 unknown 1523 19.51 2.97 - - - - -
15 β-Eudesmol 1542 19.87 14.924.88 7.289 0.496 29.00 6.46
* Kovats index ** Retention time (min.) a The values in parentheses are the experimental values for logarithm of Octanol-Water partitioning coefficients (log-
Kow). The other values were calculated by the EPI-suit v4.00 package.
A. Taherpour et al. / Natural Science 3 (2011) 104-108
Copyright © 2011 SciRes. OPEN ACCESS
Cadinene (6.13%), (–) Bornyl acetate (5.61%) are located
in the second level of the concentration in the essential
oil. Although, in accordance with the data in Table 1,
some components i.e., α-Amorphene (3.84%), α-Fenchyl
acetate (2.35%), β-Pinene (2.07%), Valencene (1.81%),
α-Humulene (1.15%), β-Maaliene (1.14%) and Ger-
macrene-D (0.85%) have the medium up to low rela-
tive percentages, could see some important compounds
with effects like mold and mildew preventive, micros-
copy, preservative and antioxidant. Biological and aroma
effects of the main and minor compounds of the essen-
tial oil of Hymenocrater longiflorus Benth. are discuss-
able in terms of their possible use in medicine, cosmetics
and foods.
α-Pinene has the highest percentage (22.47%) in this
herb. α-Pinene, is a natural bicyclic sesquiterpene that is
a constituent of many essential oils. α-Pinene and β-
Pinene. As the name suggests, both forms are important
constituents of pine resin; they are also found in the
resins of many other conifers, and more widely in other
plants. Both are also used by many insects in their
chemical communication system. α-Pinene and β-pinene
are both produced from geranyl pyrophosphate, via
cyclisation of linaloyl pyrophosphate followed by loss of
a proton from the carbocation equivalent [12].
β-Pinene with 12.06% in this herb was utilized as an
intermediate for perfumes and flavorings. It also occurs
naturally in rosemary, parsley, dill, basil, yarrow, and
rose. α-Pinene with 9.94% in this herb was utilized as
solvent for protective coatings, polishes and waxes, syn-
thesis of camphene, comphor, geraniol, terpin hydrate,
terpineol, synthetic pine oil, terpene esters and ethers,
lube oil additives, flavoring and odorant. It is also found
in the essential oil of rosemary (Rosmarinus officinalis).
β-Caryophyllene or trans-Caryophyllene is one of the
chemical compounds that contribute to the spiciness of
black pepper. β-Caryophyllene, is a natural bicyclic se-
squiterpene that is a constituent of many essential oils,
especially clove oil, the oil from the stems and flowers
of Syzygium aromaticum (cloves), the essential oil of
hemp Cannabis sativa, and rosemary Rosmarinus
oficinalis. It is usually found as a mixture with isocar-
yophyllene and α-humulene, a ring-opened isomer. Car-
yophyllene is notable for having a cyclobutane ring, a
rarity in nature [12,13].
It was found that β-eudesmol, a sesquiterpenol con-
stituent of Chinese herb antagonized organophosphate-
induced lethal toxicity by reversing the neuromuscular
failure and reducing the occurrence of convulsions [13].
Its possible antiepileptic action was further explored
in electroshock seizure mice in vivo and in high pota-
ssium treated rat hippocampal slices in vitro. At a dose
with little effect on the motor activity, β-eudesmol pre-
vented the convulsions and lethality induced by maximal
electroshock but not those by pentylenetetrazol or picro-
toxin. At sub effective doses, β-eudesmol and phenytoin
showed additive effect in preventing electroshock sei-
zures. Extracellular recording of field potentials in CA1
pyramidal layer of hippocampal slices showed that
β-eudesmol reduced the high potassium (8.5 μM)-in-
duced electrographic seizure activity. The potential of
β-eudesmol to serve as an antiepileptic or a conjuvant in
phenytoin therapy is suggested [14].
α-Copaene, a potent attractant for male Mediterranean
fruit flies. Ceratitis capitata is found as a minor com-
ponent in the essential oils of various plant species, in-
cluding its hosts such as orange, guava, and mango. De-
spite the specific attraction of male flies and the wide
distribution of the compound in host plants, the biologi-
cal significance of α-copaene remains unknown [15].
Chemically, the copaenes are tricyclic sesquiterpenes.
The molecules are chiral, and the α-copaene enantiomer
most commonly found in higher plants exhibits a negative
optical rotation of about 6°. The rare (+) -α-copaene is
also found in small amounts in some plants. It is of
economic significance because it is strongly attracting to
an agricultural pest, the Mediterranean fruit fly Ceratitis
capitata [15]. Bornyl acetate is a constituent of some
essential oils. It has been used in aromatic preparations
in the treatment of coughs.
Chemically, the cadinenes are bicyclic sesquiterpenes.
The term “cadinene” has sometimes been used in a
broad sense to refer to any sesquiterpene with the so-
called cadalane (4-isopropyl-1, 6-dimethyldecahydrona-
phthalene) carbon skeleton. Because of the large number
of known double-bond and stereochemical isomers, this
class of compounds has been subdivided into four sub-
classes based on the relative stereochemistry at the
isopropyl group and the two bridgehead carbon atoms.
The acid-catalyzed cyclization of Germacrene-D to
give cadinane and selinane sesquiterpenes has been
computationally investigated using both density func-
tional (B3LYP/6-31G*) and post Hartree-Fock (MP2/6-
31G**) ab initio methods by Setzer in 2008 [16]. It is
generally observed that essential oils containing large
concentrations of the sesquiterpene germacrene D are
typically accompanied by cadinane and muurolane ses-
quiterpenoids [16-22] and germacrene-D has been sug-
gested to serve as biogenetic precursor to a number of
different sesquiterpenoid skeletons [16,23,24]. Bülow
and König have demonstrated that germacrene-D readily
undergoes acid-catalyzed cyclization to give cadinane,
muurolane, and amorphane sesquiterpenes [16,25]. In
addition, there is concern that skeletal rearrangements
may occur during the hydrodistillation of plant materials
A. Taherpour et al. / Natural Science 3 (2011) 104-108
Copyright © 2011 SciRes. OPEN ACCESS
to obtain essential oils [16,26-29]. Bülow and König
[16,24] had found that acid-catalyzed cyclizations of
germacrene D generally give a preponderance of δ-cad-
inene, followed by γ-cadinene, and lesser amounts of α-
cadinene. The abundant δ-cadinene is consistent with the
ab initio calculations, but the calculated energies of α-
cadinene and γ-cadinene are not in agreement with the
experimental results, and would predict α-cadinene to be
more abundant than γ-cadinene. In addition, γ-cadinene is
more abundant in these essential oils than α-cadinene.
α-Cadinene has been shown to undergo acid-catalyzed
rearrangement to give β-cadinene [16,30], which in turn,
has been found to isomerize to ω-cadinene [16,30-32], in
agreement with the calculated energies; β-cadinene and
ω-cadinene are lower in energy than α-cadinene by 1.88
kcal/mole and 2.90 kcal/mol, respectively. Bülow and
König [16,24] reported that ω-cadinene can be formed
from δ-cadinene in a 1.4:1 ratio, consistent with the nearly
equal calculated energies.
It is reported and accepted that the toxicity property of
organic compounds can be predicted on the basis of the
log Kow [7]. Total biodegradation (TBd) is another useful
and important factors in chemical and biochemical stud-
ies [33]. The LC50 value is called the median lethal con-
centration and lethal concentration 50, this value gives
an idea of the relative acute toxicity of an in halable ma-
terial. One of the other important physicochemical fac-
tors of compounds is water solubility (Sw, mg.L-1 at
25ºC). In accordance with the calculated data of the com-
ponents 1-15 (see Table 1) γ-Elemene, Germacrene-D
and α-Humulene have the highest log Kow, among the
components 1-15 (7.09, 6.99 and 6.95, respectively).
α-Humulene and α-Copaene have the lowest water solu-
bility (Sw, mg.L-1 at 25ºC). β-Caryophyllene has the
highest LC50 (mg/L) and γ-Elemene, Germacrene-D and
α-Humulene are three components with lowest LC50
(0.005, 0.006 and 0.013, respectively). The total biodeg-
radation (TBd) of β-Eudesmol among 1-15 is the highest
and for β-Pinene is the lowest amount (in mol/h and
gr/h). The total biodegradation (TBd) for α-Pinene
(22.47%) (The highest percentage component) is calcu-
lated: 7.70 (mol/h) and 1.05 (gr/h). In Table 1, the val-
ues in parentheses are the experimental values for loga-
rithm of Octanol-Water partitioning coefficients (log
Kow). The other values were calculated by the EPI-suit v
4.00 package. For the other items there were not avail-
able values from data base [11].
Perhaps, the high densities of the main compounds
give some biological activities to the essential oil or to
this herb. Although no records of toxicity have been found
for this plant, it belongs to a family that includes many
poisonous plants so some caution is advised [34,35].
Hymenocrater longiflorus Benth., one of the Hy-
menocrater genus, was collected from Kurdistan area in
Iran. It is utilized as the medicinal herb for the various
purposes in local and traditional medicine by folks in
Kurdistan-Iran. Fifteen components in the essential oil of
Hymenocrater longiflorus Benth. representing fourteen
of the total oil were identified by GC and GC/MS tech-
nique. In this herb, α-Pinene, trans-Caryophyllene (β-
Caryophyllene) and β-Eudesmol have the most percent-
ages among compounds of the essential oil. Some other
components α-Copaene (9.84%), γ-Elemene (6.79%), δ-
Cadinene (6.13%), (–) Bornyl acetate (5.61%) are lo-
cated in the second level of the concentration in the es-
sential oil. α-Amorphene (3.84%), α-Fenchyl acetate
(2.35%), β-Pinene (2.07%), Valencene (1.81%), α-Hu-
mulene (1.15%), β-Maaliene (1.14%) and Germacrene-
D (0.85%) have the medium up to low relative percent-
ages among 1-15. Some of the other physicochemical
data, i.e. octanol-Water partitioning coefficients (log
Kow), the total biodegradation TB d (in mol/h and g/h),
water solubility (Sw, mg.L-1 at 25ºC) and median lethal
concentration 50 (LC50) were calculated by the EPI-suit
v4.00 package.
The authors gratefully acknowledge the colleagues in Chemistry
Department of The University of Queensland-Australia, for their useful
suggestions. We are also thankful from the Research Council of Sci-
ence and Research Campus of Islamic Azad University and Arak
branch of I. A. University.
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