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''Evaluation of the volatile oil composition and antiproliferative activity of Laurus nobilis L. (Lauraceae) on breast cancer cell line models''


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Volatile oil composition and antiproliferative activity of Laurus nobilis L. (Lauraceae) fruits and leaves grown in Jordan were investigated. GC-MS analysis of the essential oil of the fruits resulted in the identification of 45 components representing 99.7 % of the total oil content, while the leaf essential oil yielded 37 compounds representing 93.7% of the total oil content. Oxygenated monoterpene 1,8-cineole was the main component in the fruit and leaf oils. Using sulphorhodamine B assay; the crude ethanol fraction, among other solvent extracts, showed strong antiproliferative activity for both leaves and fruits, nevertheless, the fruits were more potent against both breast cancer cell models (MCF7 and T47D). At IC50 values; the mechanism of apoptosis was nevertheless different: where L. nobilis fruit proapoptotic efficacy was not regulated by either p53 or p21, L. nobilis leaf extract components enhanced the p53 levels substantially. In both extracts, apoptosis was not caspase-8 or Fas Ligand and sFas (Fas/APO-1) dependent. Our studies highlight L. nobilis as a potential natural agent for breast cancer therapy. Compared with non induced basal cells, both L. nobilis fruits and leaves induced a significant enrichment in the cytoplasmic mono-and oligonucleosomes after assumed induction of programmed MCF7 cell death.
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The article was published by Academy of Chemistry of Globe Publications © Published 03/19/2014 EISSN:
Rec. Nat. Prod. 8:2 (2014) 136-147
Evaluation of the Volatile Oil Composition and Antiproliferative
Activity of Laurus nobilis L. (Lauraceae) on Breast Cancer Cell
Line Models
Rana Abu-Dahab
, Violet Kasabri and Fatma Ulku Afifi
Faculty of Pharmacy, The University of Jordan, Amman 11942, Queen Rania Street, Amman JORDAN
(Received April 15, 2013; Revised October 06, 2013; Accepted October 09, 2013)
Abstract: Volatile oil composition and antiproliferative activity of Laurus nobilis L. (Lauraceae) fruits and
leaves grown in Jordan were investigated. GC-MS analysis of the essential oil of the fruits resulted in the
identification of 45 components representing 99.7 % of the total oil content, while the leaf essential oil yielded
37 compounds representing 93.7% of the total oil content. Oxygenated monoterpene 1,8-cineole was the main
component in the fruit and leaf oils. Using sulphorhodamine B assay; the crude ethanol fraction, among other
solvent extracts, showed strong antiproliferative activity for both leaves and fruits, nevertheless, the fruits were
more potent against both breast cancer cell models (MCF7 and T47D). At IC
values; the mechanism of
apoptosis was nevertheless different: where L. nobilis fruit proapoptotic efficacy was not regulated by either p53
or p21, L. nobilis leaf extract components enhanced the p53 levels substantially. In both extracts, apoptosis was
not caspase-8 or Fas Ligand and sFas (Fas/APO-1) dependent. Our studies highlight L. nobilis as a potential
natural agent for breast cancer therapy. Compared with non induced basal cells, both L. nobilis fruits and leaves
induced a significant enrichment in the cytoplasmic mono- and oligonucleosomes after assumed induction of
programmed MCF7 cell death.
Keywords: Laurus nobilis; Volatile oils; Anticancer; Apoptosis; Jordan. © 2014 ACG Publications. All rights
1. Introduction
Laurus nobilis L. (Lauraceae), commonly known as bay leaf, has been used as a spice
worldwide and a medicinal plant in Mediterranean countries, including Jordan. Leaves and fruits have
been reported to possess aromatic, stimulant and narcotic properties [1]. The anti-convulsive and
antiepileptic activities of L. nobilis extracts have been confirmed [2]. The leaves of L. nobilis are
traditionally used orally to treat the symptoms of gastrointestinal problems, such as epigastric bloating,
digestion, and flatulence [3]. Preliminary brine shrimp toxicity tests and few other studies related to its
cytotoxic properties were carried out on the leaf extract of Turkish L. nobilis [4]. While the majority of
the phytochemical and biological reports dealt with the leaves of L. nobilis, there has been very little
work on its fruits. The major setbacks of most available chemotherapies are the non-selective
Corresponding author: E-mail:; Phone: +96265355000; Fax:+ 96265300250
Abu-Dahab, Rec. Nat. Prod.(2014) 8:2 136-147
cytotoxicity, severe side effects, and chemo-resistance [5]. A cornerstone of newer cancer therapy is to
develop alternatives that have high specificity to induce molecular apoptosis in cancer cells.
In the last decades, newer anti-cancer drugs have been introduced, with about half of them
derived from natural sources [6-7]. In fact, natural compounds from flowering plants have played a
significant role in cancer chemotherapy. Some of these agents include vincristine and vinblastine from
Catharanthus roseus, paclitaxel and taxotere from species of yew (Taxus spp.), etoposide derived from
lignans of Podophyllum spp. and camptothecin analogues, such as topotecan, from Camptotheca
acuminata. These fundamentally cytotoxic components inhibit cell proliferation through different
mechanisms [8]. Apoptosis is a highly regulated mechanism by which cells undergo cell death in an
active way. Accordingly, one of the challenging tasks concerning cancer therapy is to induce and
augment apoptosis in malignant cells. Therefore, there is an escalating focus on natural products to
modulate apoptotic signaling pathways and their emerging molecular targets [9].
Though few reports were related to L. nobilis antiproliferative capacity [10-12]; presently in this
study, water, ethanol, butanol, ethylacetate and chloroform extracts of L. nobilis leaves and fruits as
well as their hydrodistilled volatile oils were tested for their antiproliferative activity. To shed light on
the possible anticancer mechanisms of L. nobilis leaves and fruits extracts, p53 and p21 levels, Fas
ligand and sFas and caspase-8 activities were determined, all of which are strongly associated with the
signal transduction pathway of apoptosis [13-15].
2. Materials and Methods
2.1. Plant Material and Preparation of Crude Extracts
Leaves and fruits of L. nobilis L., collected from the trees grown in the campus of The
University of Jordan in June 2010, were identified by Prof. Barakat Abu Irmaileh (Faculty of
Agriculture, The University of Jordan). Leaves and fruits were air dried at room temperature (RT) in
the shade until constant weight. Voucher specimens for L. nobilis fruits [1LAUR FMJ] and leaves
[2LAUR FMJ] have been deposited in the Department of Pharmaceutical Sciences, Faculty of
Pharmacy, the University of Jordan.
Each 10 g of the dried and coarsely powdered plant material was refluxed for 30 min using
different solvents, kept overnight, filtered and solvents were evaporated. The ethanol extracts of the
fruits and leaves were tested for the presence of different classes of secondary metabolites using Thin
Layer Chromatography (TLC) [16]. Coated analytical TLC plates were procured from Merck. For
biological activity tests, 100 mg of the extracts were dissolved in 10 mL DMSO (stock solution).
2.2. Distillation of Plant Material
Air dried plants were coarsely powdered and then hydro-distilled using a Clevenger apparatus
for 3 h. The distillation was repeated twice and the oils obtained were pooled separately, dried over
anhydrous sodium sulfate (Na
) and stored at 4º C in amber glass vials until analysis.
2.3. GC-MS and GC-FID Analysis
About 1 µL aliquot of each oil sample, appropriately diluted to 10 µL in GC grade n-hexane,
was subjected to qualitative and quantitative GC-MS analysis. A hydrocarbon mixture of n-alkanes
) was analyzed separately by GC-MS under the same chromatographic conditions using the
same DP-5 column. Identification of compounds was based on the built-in libraries (NIST Co and
Wiley Co, USA) and by comparing their calculated retention indices (RI) relative to (C
) n-
alkanes literature values, measured with columns of identical polarity, or in comparison with authentic
samples [17].
α- and β-pinenes, p-cymene, limonene, linalool (Fluka, Buchs, Switzerland), eugenol,
and sabinene hydrate (Sigma-Aldrich, Buchs, Switzerland) were used as reference substances in GC-
MS analysis. GC-grade hexane and analytical reagent grade anhydrous Na
were from Scharlau
(Barcelona, Spain) and UCB (Bruxelles, Belgium), respectively. Each sample was analyzed twice.
Laurus nobilis antiproliferative activity
2.4. In vitro Assay for Antiproliferative Activity
Cell lines under investigation were human breast adenocarcinoma (MCF7, ATCC no. HTB-22)
and human ductal carcinoma (T47D, ATCC no. HTB-133). Cells were cultured in RPMI media
fortified with 10% heat inactivated bovine serum, 1% of 2 mmol/L L-glutamine, 50 IU/mL penicillin,
and 50 µg/mL streptomycin. Human periodontal fibroblasts (PDL), which are a primary cell culture,
were kindly provided by Dr. Suhad Al-Jundi and Dr. Nizar Mhaidat from Jordan University of Science
and Technology, Irbid, Jordan.
Cells were seeded with a density of 5000 cell/well (15 000 cell/cm
) and incubated at 37° C in a
humidified atmosphere containing 5% CO
. After 24 h, the cells were treated with the extracts, volatile
oils, and controls. Test compounds were incubated with the cells for 72 h at 37º C in humidified
conditions containing 5% CO
. At the end of the exposure time, cell growth was measured using the
sulphorhodamine B (SRB) assay as described earlier [18-19]. As positive controls, cisplatin and
doxorubicin were used [19].
2.5. Tests for Apoptosis
Quantum Protein (Bicinchoninic Protein assay kit; EuroClone S.p.A, Siziano, Italy),
Nucleosome ELISA (Roche Diagnostics GmbH; Mannheim, Germany), human total p53 ELISA,
human total p21 ELISA, human Fas Ligand, human sFas immunoassay ELISA, caspase-8
colorimetric assay kits, wash buffer and substrate and stop solutions (R&D Systems Europe, Ltd;
Abingdon, UK) were used.
2.6. Measurement of Apoptosis by ELISA
In our preliminary investigations, none of T47D selected extrinsic apoptosis biomarkers, namely
FasL, sFas or caspase 8, were differentially or significantly up-regulated/activated in comparison to
MCF7’s. Thus, the decision was formulated to preferentially select for MCF7 over T47D in the
antiproliferative action mechanism studies of L. nobilis aerial parts. In addition, it has been reported
that proteins implicated in apoptosis regulation are more strongly expressed in MCF7 as compared to
T47D [20]. The induction of apoptosis was assayed using the nucleosome ELISA kit. As described in
the manufacturer's protocol, this kit is a photometric enzyme-immunoassay for the determination of
cytoplasmic histone-associated-DNA-fragments after induced cell death. MCF7 cells were incubated
with vehicle alone (0.1% DMSO) and with the obtained IC
’s of the extracts under investigation for
72 h compared to the untreated (non-induced) basal cell incubations.
2.7. Assays of the Levels of p53, p21/WAF1, FasL (Fas Ligand) and sFas (Fas/APO-1)
MCF7 cells were treated as above and as described in the manufacturer’s protocol. The samples
of cell lysate were placed in 96-wellplates coated with monoclonal antibodies, and incubated for 2 h
(sFas, p53, p21, or FasL) at RT. After removing the unbound material by washing buffer, horseradish
peroxidase conjugated streptavidin was added. The absorbance was measured at 450 nm, and
concentrations of p53, p21, FasL and sFas were directly determined by interpolating from standard
curves. Results are presented as the percentage of the change of respective non-induced control
2.8. Assay for Caspase-8 Activity
As per the manufacturer’s instructions, cell lysates were incubated with peptide substrate in
assay buffer (100 mM NaCl, 50 mM HEPES, 10 mM dithiothreitol, 1 mM EDTA, 10% glycerol, 0.1%
CHAPS, pH 7.4) for 2 h at 37
C. The release of p-nitroaniline was monitored at 405 nm. Results are
represented as the percentage of the change of the activity compared to the untreated control cells.
2.9. Statistical Analysis
Results were expressed means (as %control) ± S.E.M (standard error of the mean). Statistical
comparisons of the results were determined by ANOVA followed by Dunnett’s post-test whenever
appropriate using Graphpad Prism (version 3.02 for windows; GraphPad Software, San Diego, CA,
Abu-Dahab, Rec. Nat. Prod.(2014) 8:2 136-147
USA). Values of the means of untreated control and treated cells were considered significantly
different if P<0.05 and highly significantly different if P<0.01 and P<0.001.
3. Results and Discussion
3.1. Volatile Oil Composition and Phytochemical Screening of Crude Extracts by TLC
After hydrodistillation, leaves and fruits of L. nobilis afforded yellowish oils with a yield of
moisture-free 4.3 and 2.8 % (v/w), respectively. The retention indices and relative percentages of the
identified compounds are presented in Table 1.
GC-MS analysis of the hydrodistilled essential oil of the fruits resulted in the identification of
45 components representing 99.7 % of the total oil content. Hydrocarbon and oxygenated
monoterpenes were found to have the highest contribution to the hydro-distilled essential oil
comprising 84.9 % of the total oil content. 1,8-cineole (eucalyptol) was the main oxygenated
monoterpene detected, accounting for 29.8 % of the total oil content. With the exemption of α-
terpinylacetate (5.6 %), α-terpineol (1.2 %) and γ-terpineol (1.5 %), other detected oxygenated
monoterpenes were found to occur in concentrations less than 1%. Sesquiterpenes were found only in
low concentration (12.7 %) with ß-elemene being the main constituent (6.2 %). GC-MS analysis of the
leaf essential oil resulted in the identification of 37 compounds representing 93.7 % of the total oil
content. 1,8-cineole (36.8%), α-terpinylacetate (14.6 %) and terpinene-4-ol (6.4 %) were the major
components of the monoterpenoid fraction (83.3 %). Sesquiterpenoids were detected only at a
concentration of 1.4 %.
Crude ethanolic extracts of L. nobilis leaves and fruits were rich in flavonoids and terpenoids. In
TLC experiments, the occurrence of the well known flavonoids quercetin, luteolin, kaempferol and
apigenin were identified in both the leaf and fruit extracts.
Volatile oil composition of the fruits and leaves of L. nobilis has been studied by several
researchers. A comparison of these reports showed differences in the concentration of the major
components. In addition to the genetic factors, determining the chemotype of the species, and the
season during which the plants are collected, the environmental conditions, soil characteristics,
methods of drying, extraction and analytical conditions do contribute to the differences in oil
composition [21]. Consistent with our findings, 1,8-cineole is the main component of the volatile
fraction as in all previous studies. The leaves of L. nobilis collected from Lebanon yielded 35.15%
1,8- cineole while the oil obtained from young and old leaves collected from North Black Sea region
of Turkey yielded 24.2 % and 32.1 %, respectively [22] . Two other studies were carried out with the
leaf oil from different location in South Turkey contained higher percentages for 1,8-cineole (46.6 %,
47.6 % , 59.9 % and 44.7 %, respectively) [23-24]. The findings of the current study are quite similar
to those of Loizzo et al. [25], and stands at 36.8 %, although earlier in our laboratories, using the fresh
leaves, higher percentage was detected (40.9 %) [18]. The lowest concentration for 1,8-cineole was
reported from Portugal (27.2%) [26]. On the other hand, the concentration of 1,8- cineole in the hydro-
distilled oil from the fruits of L. nobilis in the present study is higher (29.8 %) compared to the
studies from Lebanon (9.4 %) and Turkey (9.5 % and 18.1 %, 20. 5 % , 17.4 %, respectively) [22-23].
Fluctuations were recognized with other constituents of the volatile fractions of the leaves and
fruits, all studied L. nobilis oils from the Mediterranean countries were rich in monoterpenoids while
sesquiterpenoids were detected in very low concentrations. In the present study, monoterpene
hydrocarbons and oxygenated monoterpenoids had nearly equal share in the oil of the fruits (43.6 %
and 41.3 %, respectively) while the leaf oil contained predominantly oxygenated monoterpenoids
(66.2 %). Still oxygenated sesquiterpenes were absent in L. nobilis fruit oil. The main detected
sesquiterpene in the bay fruit oil was ß-elemene (6.2 %). The latter compound found in the leaf oil
only at a concentration of 0.3 %. Moreover, β-caryophyllene and caryophyllene oxide were detected in
both oils in concentrations below 2 %.
Laurus nobilis antiproliferative activity
Table 1. Comparison of the chemical composition of the essential oils hydrodistilled from the leaves
and fruits of Laurus nobilis. Results present the average of 2 independent trials
RI* Compound Dry leaves
852 (E)-3-hexanol 1.0 -
864 (Z)-3-hexanol 3.8 -
α-thujene 0.1 0.5
934 α-pinene 4.6 10.9
937 citronellene tetrahydro 0.1 -
-citronellene 0.2 -
951 camphene 0.5 1.3
sabinene 3.1 4.4
980 β-pinene 3.6 8.4
985 trans-m-mentha-2,8-diene, 0.1 -
989 myrecene 0.4 -
992 dehydo-1,8-cineole 0.2 -
1009 α- phellandrene - 9.0
-2 -carene 0.4 -
α- terpinene 0.4 0.4
1026 o-cymene 1.0 -
p-cymene 0.3 2.5
limonene 1.6 2.5
1,8-cineole 36.8 29.8
1046 (E)-
-ocimene - 3.2
1059 γ-terpinene 0.6
cis-sabinene hydrate 0.6 0.2
terpinolene 0.1 0.1
linalool 2.6 0.4
1128 1-terpineol 0.2 0.1
1146 cis-sabinol 0.3 0.2
1150 camphor - 0.2
1173 p-mentha-1,5-dien-8-ol 0.6 -
terpinene-4-ol 6.4 0.2
1177 borneol - 0.4
-terpineol - 1.2
γ-terpineol 1.8 1.5
1208 p-cymene 9-ol - 0.2
1271 iso-3-thujyl acetate 0.5 -
isobornylacetate 1.1 0.8
cis-dihydro-α-terpinylacetate 0.3 0.3
1340 δ-elemene 0.4 -
α-terpinylacetate 14.6 5.6
1360 nerylacetate - 0.2
1372 α-ylangene - 0.3
-cubebene - 0.1
-elemene 0.3 6.2
methyleugenol 4.2 0.2
1421 2,5-dimethoxy-p-cymene 0.2 -
-caryophyllene - 1.1
1438 α-guaiene - 0.5
1444 aromadendrene - 0.3
1452 cis-muurola 3,5-diene - 0.2
Abu-Dahab, Rec. Nat. Prod.(2014) 8:2 136-147
1459 α-humulene - 0.3
1484 γ-muurolene - 0.7
-selinene 0.4 -
1493 germacrene D - 0.5
- selinene - 0.6
1505 α-selinene - 1.0
1511 germacrene A - 0.2
1517 γ-cadinene - 0.5
1521 δ-cadinene - 0.2
1525 undecenoic acid-10-methyl,
methyl ester - 0.8
1586 caryophyllene oxide 0.3 -
1596 dodecenoic acid ethyl ester - 1.1
Total identified 93.7 99.7
Monoterpenoids 83.3 84.9
Monoterpenoid hydrocarbons 17.1 43.6
Oxygenated monoterpenoids 66.2 41.3
Sesquiterpenoids 1.4 12.7
Sesquiterpene hydrocarbons 1.1 12.7
Oxygenated sesquiterpenes 0.3 -
Phenylpropanoids 4.2 0.2
Miscellaneous 4.8 1.9
Unidentified 6.3 0.3
* Retention indices (RI) calculated on (DB-5MS) column, ** Percentage is given as the average of two
independent measurements. Compounds are listed based on their elution order on the corresponding column.
refers to RI of the leaves,
refers to RI of the fruits.
3.2. Antiproliferative Activity
The in vitro antiproliferative activity of the different fractions is shown in Table 2. Results
present the IC
values of the fractions (concentration of the extract needed to reduce proliferation by
50% after 72 h of incubation compared to control wells). IC
values were determined by plotting dose
response curves for the fractions under investigation in the range of 0.1 to 100 µg/mL). The IC
values of reference drugs; cisplatin and doxorubicin were 7.3 ± 1. 9 µM and 0.16 ± 0.0 µM for MCF7
cells, 21.3 ± 9.7 µM and 0.2 ± 0.0 µM for T47D cells respectively.
Table 2. The antiproliferative activity of Laurus nobilis leaves- and fruits-extracts on MCF7
and T47D cell lines.
Leaves Fruits Leaves Fruits
Ethanol 48.2±5.2 28±1.7 19.8±4.3 12.3±4.0
Chloroform 48.8±10.3 31.2±5.24 58.2±14.1 35. 6 ± 5.6
Butanol Non toxic 72. 5±5.8 Non toxic 75.4±6.4
Ethyl acetate 61.0±18.4 20.6 ± 4.5 27.9±1.3 33.7±13.9
Aqueous Non toxic Non toxic Non toxic Non toxic
Volatile oil 93.1±4.7 41.9±3.3 64.3±3.1 142±43.6
Results present the IC
in µg/mL (concentration needed to reduce cell proliferation by 50%). Results
present the average of at least two determinations on two cell line passages and each is an average with
standard deviation of four wells.
For both cell lines, L. nobilis fruit extracts showed higher antiproliferative activity compared to
the leaf extracts. In both parts, aqueous and butanol fractions demonstrated weak or no reduction in
Laurus nobilis antiproliferative activity
cellular viability at the concentration range under investigation. The criteria of cytotoxic activity for
the crude extracts, as established by the American National Cancer Institute (NCI) is an IC
less than
30 µg/mL in the preliminary assay [27]. The ethanol extract of the fruits exhibited prominent
antiproliferative activity with an IC
of 12.3 µg/mL for T47D cell line and 28 µg/mL for MCF7 cells,
while the IC
values of the leaves were higher (19.8 µg/mL for T47D cells and 48.2 µg/mL for
Similar results were observed for L. nobilis grown in Turkey, where methanol extracts of leaves,
fruits and seeds were evaluated for their ovarian cytotoxic activity and DNA damaging properties
against three types of yeast. In this study, the most cytotoxic extract was that of the fruit and further
identification led to cytotoxic sesquiterpenes isolated from the fruits rather than from the leaves or
seeds [28]. In another study, L. nobilis leaves from Palestine were also tested for their anticancer
activity against MCF7 as well as L929sA (murine fibrosarcoma cell line) and MDA-MB 231(breast
cancer cell line). Dichloromethane: methanol extracts were used and here the leaves were reported as
not cytotoxic against the breast cancer cell line models used and had an IC
of 174 µg/mL against the
murine fibrosarcoma [29]. The concentration range of the crude extracts under investigation was
nevertheless not mentioned.
Cytotoxic activity has been reported for the crude bay leaf extract and for sesquiterpene lactones
isolated from the leaves and fruits of L. nobilis. The cytotoxicity was evaluated in vitro using human
tumor cell lines such as Jurkat, HL-60, LoVo, SH-SY5Y, MCF7 and A2780 and promising results
were obtained, especially with the isolated sesquiterpene lactones [28-31].
The antiproliferative activity of the volatile oils
and pure compounds
was investigated. Firstly, the
crude oils were tested for their antiproliferative activity and here, the activity was less than that for
both the ethanol and ethylacetate fractions. Secondly, the antitumor propensities of selected pure
volatile compounds of the volatile oil fraction were tested, this included, 1,8-cineole, α-pinene, β-
pinene, limonene, linalool, borneol, β-caryophyllene and caryophyllene oxide. From those, with the
exception of β-caryophyllene and caryophyllene oxide, no/or minimal antiproliferative activity was
detected from 0.1 up to 100 µg/mL. β-Caryophyllene and caryophyllene oxide exhibited potent
biological activity; 14.4 ± 1.6 µg/mL for β-caryophyllene and 8.1 ± 0.7 µg/mL for caryophyllene
oxide against MCF7 cells and 14.4 ±1.3 µg/mL for β-caryophyllene and 6.1 ± 0.8 µg/mL for
caryophyllene oxide against T47D cells.
Although present in low concentrations; β-caryophyllene and caryophyllene oxide, could have
contributed to the antiproliferative activities observed with the volatile oil fractions and crude extracts
of the tested plants. Moreover, the well known flavonoids quercetin, luteolin, kaempferol and apigenin
were identified in the ethanol extracts. In earlier publications [19] the IC
of luteolin was determined
(5.3 ± 0.4 µg/mL for MCF7 cells and 4.3 ± 0.1 µg/mL for T47D) and it was recognized as a potent
antiproliferative agent in Eminium spiculatum. It can be concluded that the observed antiproliferative
activity of the extracts are attributed to the flavonoids in addition to the mentioned pure volatile
compounds. It was postulated by Kwom et al. [32] that induction of apoptosis by kaempferol and
quercetin was caspase-3 dependent. Similar caspase-3 (and caspase-7) dependent apoptotic pathways
were described for luteolin [33].
β-Elemene (found in L. nobilis fruits at a percentage of 6.9 but only 0.3 % in its leaves) may
contribute to the differences in cytotoxic activity of the crude volatile oils as well as the ethanol,
chloroform and ethyl acetate extracts from the two different aerial parts. β-Elemene has been reported
to have anticancer activity against cancers of brain, breast, lung and other tissues after different in vivo
and in vitro experiments. The mechanism of its anticancer effect is still unclear; nevertheless, it could
be due to direct cytotoxic activity, and inhibition of free radical formation. Several reports attribute
this activity to induction of apoptosis and suppression of tolemerase activity [34].
In an attempt to study the safety of these extracts, the antiproliferative activity of the crude
ethanol extract was tested against normal freshly excised human periodontal cells. In those, and after
72 h incubation, the IC
values for both parts were higher than those determined against the selected
cancer cell lines; (81.3 µg/mL for the fruits and 41.8 µg/mL for the leaves). This suggests its
preferential selectivity for cancer tissues over normal ones.
Abu-Dahab, Rec. Nat. Prod.(2014) 8:2 136-147
3.3. Effects of Fruit and Leaf Extracts on Induction of Apoptosis as Detected and Quantified
by Nucleosome ELISA
Apoptosis is governed by a complex network of effector molecules. It is characterized by DNA
fragmentation, cell shrinkage and nuclear condensation, and phosphatidylserine translocation from the
inner to the outer leaflet of the plasma membrane bilayer [5]. Cisplatin's potent cytotoxicity is
primarily mediated by its ability to cause DNA damage and subsequent apoptotic cell death. However,
it was found that its anti-tumerogenic efficacy and proapoptotic features in many cancer cell lines
involves the activation of different forms of cell death, i.e. the receptor mediated apoptotic extrinsic
pathway, the intrinsic pathway as in alterations in mitochondrial membrane permeability and
cytochrome c release and a death process mediated by endoplasmic reticulum stress [35].
Compared with basal control wells, 28 µg/mL of L. nobilis fruit extract induced a significantly
detectable enrichment in the cytoplasmic mono- and oligonucleosomes after assumed induction of
programmed MCF7 cell death (227.3 ± 23.3%, p<0.05, n=4, Figure 1). More importantly, 48.2 µg/mL
of L. nobilis leaf extract augmented highly significantly cytoplasmic enrichment following
polynucleosomes disintegration and DNA fragmentation in treated MCF7 wells over 72 h ( 1295 ±
37.2 %, n=4, p<0.001 vs. basal (untreated) controls, the same figure).
3.4. Effect of L. nobilis Fruit and Leaf Extracts on Receptor-mediated Apoptosis-target
Previous reports have indicated that MCF7 cells have a normal (non-mutated) tumor suppression
gene, p53. Cisplatin is a chemotherapeutic drug used for several human malignancies. Exceptionally,
cisplatin 72 hours incubation induced a highly significant augmentation of p53 levels (233.8 ± 10.4%,
n=4, p<0.001 vs. basal control MCF7 wells).
In examining the effects of L. nobilis fruit and leaf extracts on cell cycle regulatory molecules,
including p53 and its downstream molecule p21, Figure 2 demonstrates that L. nobilis fruit (28
µg/mL) enhanced the expression of neither protein at the examined incubation time. Thus, L. nobilis
fruit extract proapoptotic efficacy might not be regulated by either p53 or p21. Interestingly, our
results indicate that L. nobilis leaf extract components enhanced the p53 levels highly substantially
(140.1 ± 4.4%, n=4, p<0.001 vs. basal control MCF7 wells, Figure 2) less effectively than cisplatin,
although mostly unlikely, L. nobilis leaf extract proapoptotic effect was p21-independent. To establish
the sequence of events involved in L. nobilis induction of apoptosis, the recruitment of sFas/FasL-
mediated execution of apoptosis was investigated. Over 72 h, sFas/FasL system was not selectively
upregulated in either L. nobilis-parts mediated inhibition of proliferation in MCF7 treatments (Figure
3). We next examined the downstream caspase of sFas/FasL system, and consistent with our findings
on the lack of sFas/FasL system modulation, neither of L. nobilis parts increased caspase 8 activity at
72 h compared to basal control wells (Figure 4).
Laurus nobilis antiproliferative activity
Control Laurus nobilis fruit Laurus nobilis leaf
DNA Fragmentation and nu cleosomes
levels (As %Control)
Figure 1. Effects of antiproliferative Laurus nobilis extracts on proapotosis DNA fragmentation.Cell lysates
containing cytoplasmic oligonucleosomes of apoptotic cells were analyzed by means of nucleosome ELISA kit
to investigate the induction of apoptosis in MCF7 cells by antiproliferative Laurus spp. Results expressed as
%control are mean ± SEM (n=4 independent determinations). *P<0.05 and ***P<0.001 indicates that bioactive
plants extracts had highly significant statistical differences compared to control (non-induced) wells and, as
analyzed by ANOVA followed by Dunnett's test.
Control Laurus nobili s fruit Laurus nobilis leaf
p53/p 21 Levels (As %Control)
p53 p21
Figure 2. Effects of antiproliferative Laurus nobilis on protein expression of p53/p21 in Human breast
adenocarcinoma MCF7 cells, as determined by p53/p21 ELISA kits. Results expressed as % control are mean ±
SEM (n=4 independent replicates). ***P<0.001 indicate that plants' incubations had highly significant statistical
differences vs. control (basal non- induced) wells, as analyzed by ANOVA followed by Dunnett's test.
Abu-Dahab, Rec. Nat. Prod.(2014) 8:2 136-147
Control Laurus nobilis fruit Laurus nobilis leaf
sFas/ FasL (As %Control)
sFas FasL
Figure 3. The lack of Fas/Fas ligand apoptotic system involvement in Laurus nobilis induction of apoptosis in
MCF7 cells. Results expressed as %control are mean ± SEM (n=4 independent replicates). None of the
bioactive plants’-treatment wells had a statistically significant difference vs. control (non-induced) incubations,
as analyzed by ANOVA followed by Dunnett's test.
Control Laurus nobilis fruit Laurus nobilis l eaf
Caspas e 8 Activity (As %Control)
Figure 4. The lack of activation of caspase -8 in MCF7 cells by antiprolifertaive Laurus nobilis extracts. Results
are expressed as %control are mean ± SEM (n=4 independent determinations). None of the bioactive plants’-
treatment wells had a statistically significant difference vs. control (non-induced) incubations, as analyzed by
ANOVA followed by Dunnett's test
findings of the present study coincide with those of Jiang et al. [36], where p53 activation
was an early signal for apoptosis during cisplatin treatment [36]. Unequivocally, only L. nobilis leaf
extract evoked a highly marked increase in p53 without a concomitant increase in the downstream
effector molecule p21. The pro-apoptotic efficacy of fruits and leaf extracts was further verified and
substantiated, at least in part, by DNA-fragmenting executions. Both extracts, on the other hand, were
unable to augment the assembly of the MCF7 death-inducing signaling complex responsible for the
activation of caspase-8 and thus unable to enhance MCF7 cells’ extrinsic apoptosis cascade. This
signified the caspase-8 independent action mechanism of these extracts. Importantly, caspases are
very well known to act as key intermediates of apoptosis and to contribute to the apoptotic
morphology through the cleavage of various cellular substrates. Consequently, it can be hypothesized
that L. nobilis antiproliferative effectiveness may invoke other possible pathways and further studies
are necessary to investigate the precise mechanisms responsible. Fruits and leaves did not seem to
target succinctly the same signal transduction effectors. Hence, more elaborative investigation may
verify the plant’s promising multi-targeted malignancy therapeutics.
Taken together, the present data highlight L. nobilis as a potential natural agent for breast cancer
therapy. They also present L. nobilis important implication as a safe and effective alternative to
conventional breast cancer intervention.
Laurus nobilis antiproliferative activity
This work has been supported by an SRTD grant (contract JO/2008/RGS/034). The technical
assistance of Miss Lara Majdalawi and Mr. Ismail Abaza is appreciated.
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© 2014 ACG Publications
... Also, Laurus nobilis L. is known as bay leaf, sweet bay, bay laurel, Roman laurel or daphne, and known AL Ghar in Arabic island of the Lauraceae family and is remain an evergreen Mediterranean shrub whose leaves have traditionally been used in cuisines and folk medicine due to their beneficial health effects, which can nowadays be scientifically explained by various biological activities of the leaf extracts. Phytochemical analysis has shown that such plant containing a lot of valuable compounds such as volatile and non-volatile oils, flavonoids, tannins, sesquiterpenic alcohols, alkaloids, minerals and vitamins (Patrakar et al., 2012 andAbu-Dahab et al., 2014). In addition 1,8-cineole (51%) and α-terpinyl acetate (10%) were considerably being the main compounds in Laurus nobilis essential oils (Peris and Blázquez, 2015). ...
... At the IC 50 value, the mechanisms of apoptosis are different when the proapoptotic efficacy of L. nobilis fruits is not regulated by p53 or p21, and the component of the leaves extract substantially increased p53 level. In both extracts, apoptosis is independent of caspase-8 or Fas ligand [110]. ...
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Breast cancer is the second highest cancer-related death worldwide. The treatment for breast cancer is via chemotherapy; however, occurrences of multidrug resistance, unselective targets, and physicochemical problems suggest that chemotherapy treatment is ineffective. Therefore, there is a need to find better alternatives. Essential oil is a plant secondary metabolite having promising bioactivities and pharmacological effects, including anti-breast cancer capabilities. This review intends to discuss and summarize the effect of essential oils on anti-breast cancer from published journals using keywords in PubMed, Scopus, and Google Scholar databases. Our findings reveal that the compositions of essential oils, mainly terpenoids, have excellent anti-breast cancer pharmacological effects with an IC50 value of 0.195 μg/mL. Hence, essential oils have potential as anti-breast cancer drugs candidates with the highest efficacy and the fewest side effects.
... However, the fruits displayed stronger effect against both breast cancer cell models. It was observed that apoptosis mechanism of these extracts was not caspase-8 or Fas Ligand and sFas (Fas/APO-1)-dependent (Abu-Dahab et al. 2014). ...
Laurus nobilis L. is evergreen aromatic shrubs or trees, belongs to Lauraceae family, and is cultivated because of its aromatic leaves and ornamental interest. This chapter first summarized the description and distribution of the plant. Its chemical composition and traditional use were demonstrated in detail. The biological activities of its extracts, fractions, and pure compounds have been highlighted for further studies of the researchers. Besides, its toxicity and allergenicity properties were indicated.Keywords Laurus nobilis Traditional useChemical compositionBiological activities
... It is an evergreen plant and grown as high-value spice crop in that region, and as an ornamental plant throughout Europe and America. Phytochemical analysis has shown that such plant containing a lot of valuable compounds such as volatile and non-volatile oils, flavonoids, tannins, sesquiterpenic alcohols, alkaloids, minerals, and vitamins (Kilic et al., 2004 andAbu-Dahab et al., 2014). The dried leaves of laurel are used extensively in cooking and its essential oil is generally used as flavoring materials in food industry (Bauer and Garbe, 1985). ...
... *p<0.05 with respect to control.Terpinene. In accordance to the present findings, 1,8cineole is the major component present in most of leaf oil and other parts of the L. nobilis plant harvested from different world locations(Abu-Dahab et al., 2014;Said and Hussein, 2014). Surprisingly, the second major constituent in the MeAc extract, 5,8-Epoxy-15-nor- ...
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Laurus nobilis, commonly known as bay, is used in folk medicine as a remedy for many ailments. The present study investigates the protective effect of L. nobilis leaves extract against high fat diet-induced type 2 diabetes in rats. Animals were divided into group 1 (control), groups 2, 3, and 4 (bay leaves aqueous (AQ) extracts; 50, 100, and 250 mg/kg of body weight, respectively), and groups 5, 6, and 7 (bay leaves methanol/acetone (MeAc) extract; 50, 100, and 250 mg/kg of body weight, respectively). Animals were fed an isocaloric high fat diet for four weeks. The intake of bay leaves extracts was associated with a significant decrease in serum levels of glucose (AQ, 100 and 250 mg/kg; MeAc, 50, 100, and 250 mg/kg) and serum triglyceride (AQ, 250 mg/kg; MeAc, 100, and 250 mg/kg) as well as lower abdominal fat (all AQ and MeAc groups) and body weight gain (MeAc groups only). In conclusion, L. nobilis leaves extract intake provides a protective remedy against high fat diet-induced type 2 diabetes.
... Linoleic acid has been reported for anticancer activity in colorectal cancer (Cheng et al., 2019). α-Pinene was reported for the activity against breast cancer cell line (MDA-MB-231, MCF-7) (Abu-Dahab et al., 2014). 1,2-Benzenedicarboxylic acid, mono(2-ethylhexyl) ester have pronounced anticancer activity against liver cancer cell line HepG2, but are less toxic against 3T3 (Selvakumar et al., 2019). ...
The pharmacological importance and ecofriendly nature of medicinal plants holding a unique edge in the arena of pharmaceutical industries. Therefore, the current research was aimed to evaluate the phytochemical constituents and potential antioxidant, in vitro anticancer and antibacterial activity of Carpesium nepalense seeds essential oil. The analysis performed through Gas chromatography/Mass spectroscopy confirmed the presence of different types of biologically active compounds. At the concentration of 500µg/mL, n-hexane fraction of C. nepalense showed highly significant (P<0.001) antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid and superoxide assays with the percentage inhibitions of 86.60±1.6%, 82.55±1.0% and 80.50±1.0% respectively. The extract also produced highly significant anticancerous activity against different cell lines at 500µg/mL. The significant antibacterial activity of extract was observed against bacterial strains with the zone of inhibitions of 24.3±0.8, 28.20±0.10, 22.33±0.11 and 33.22±0.10 mm respectively. The significant damage in bacterial cell membranes was also observed in atomic force microscopic analysis. In the light of obtained findings, it is concluded that C. nepalence proved to be a potential candidate as an alternative medicinal agent.
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Bay laurel leaves, also known as bay leaves, are an important herb in many cuisines around the world. In addition to their use in cooking, bay leaves have also been used for their medicinal properties and are thought to have anti-inflammatory and antimicrobial effects. Gas chromatography/mass spectrometry (GC-MS) device was used to determine the secondary metabolites in the essential oil of bay laurel leaves samples kept at different temperatures (−22, −20, −18, 2, 4, 6, and 22°C) and storage times (1, 2, and 3 months). In this research, temperature (°C) and storage time (month) were used as input parameters in the neural network. On the other hand, alpha-pinene, beta-pinene, sabinene, 1.8-cineole, gamma-terpinene, cymenol, linalool, borneol, 4-terpineol, caryophyllene, sabinene, alpha-terpineol, germacrene-D, alpha-selinene, methyl eugenol, caryophyllene oxide, spathulenol, eugenol, and beta-selinenol were used as an output parameter. Considering the R² values obtained from the artificial neural network analysis, R² values of 0.97156 for the test, 0.98978 for the training, 0.98998 for the validation value, and 0.98831 for all values were obtained.
Traditionally, Laurus nobilis is used for the treatment of earaches and skin rashes as well as rheumatism. The most common technique to isolate the oil is hydro-distillation and steam-distillation. The investigation presented in this paper was aimed to unravel the antimicrobial activity and chemical composition of essential oil in the leaves of L. nobilis grown in Oman. The essential oil was extracted from the leave of the selected plant species by hydro distillation using Clevenger type apparatus. The antimicrobial assay was done by disc diffusion methods against three bacterial strains, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, and one fungal strain: Candida albicans. The isolated essential oil was analyzed by gas chromatography-mass spectrometry (GC-MS). The percentage yield of the essential oil was 0.064% (w/w). The essential oil was found actively against the applied bacterial and fungal strains. The highest activity was found against S. aureus and the lowest was against E. coli, and the order was S. aureus > P. aeruginosa > E. coli. The essential oil was also active against the fungus C. albicans. The range of inhibition zones was 6–14 mm. The results of GC-MS analysis showed (E)-β-caryophyllene to be the major component about 59.62%. Other major components included α-selinene (14.03%), α-humulene (8.65%), β-selinene (4.99%), and α-pinene (4.98%). In addition, several minor components were found in the essential oil of L. nobilis. Based on the experimental results, it showed that the plant species that grown in Oman were a potential source of therapeutic agents. In conclusion, the essential oil and the plant could be used as natural and potential therapeutic agents to treat earaches, skin rashes, and rheumatism.
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Laurus nobilis L. is an aromatic medicinal plant widely cultivated in many world regions. L. nobilis has been increasingly acknowledged over the years as it provides an essential contribution to the food and pharmaceutical industries and cultural integrity. The commercial value of this species derives from its essential oil, whose application might be extended to various industries. The chemical composition of the essential oil depends on environmental conditions, location, and season during which the plants are collected, drying methods, extraction, and analytical conditions. The characterization and chemotyping of L. nobilis essential oil are extremely important because the changes in composition can affect biological activities. Several aspects of the plant’s secondary metabolism, particularly volatile production in L. nobilis, are still unknown. However, understanding the molecular basis of flavor and aroma production is not an easy task to accomplish. Nevertheless, the time-limited efforts for conservation and the unavailability of knowledge about genetic diversity are probably the major reasons for the lack of breeding programs in L. nobilis. The present review gathers the scientific evidence on the research carried out on Laurus nobilis L., considering its cultivation, volatile composition, biochemical and molecular aspects, and antioxidant and antimicrobial activities.
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Habb-ul-Ghar (Laurus nobilis L., fruit) is used in the Unani and other traditional systems of medicine since ancient times. It has been also used in culinary and pharmaceutical industries. Various phytoconstituents were isolated from laurel fruit, like monoterpenes, sesquiterpenes, fatty acids, flavonoids, phenolic acid, and some minerals. Many pharmacological studies have been carried out to explore its anti-oxidant, antimicrobial, antiproliferative, antinociceptive, and anti-inflammatory activities. This review will provide a comprehensive overview only about fruit of Laurus nobilis with special reference to Unani medicine. Keywords: Habb ul Ghar; Laurus nobilis; Laurel fruit; Unani medicine
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Acetone extracts of selected plant species were evaluated for their in vitro cytotoxicity against a noncancerous African green monkey kidney (Vero) cell line and an adenocarcinoma cervical cancer (HeLa) cell line. The plants studied were Origanum vulgare L. (Oregano), Rosmarinus officinalis L. (Upright and ground cove rosemary), Lavandula spica L. (Lavender), Laurus nobilis L. (Bay leaf), Thymus vulgaris L. (Thyme), Lavandula x intermedia L. (Margaret Roberts Lavender), Petroselinum crispum Mill. (Curly leaved parsley), Foeniculum vulgare Mill. (Fennel), and Capsicum annuum L. (Paprika). Antioxidant activity was determined using a quantitative DPPH (1,1-diphenyl-2-picryl hydrazyl) assay. The rosemary species exhibited effective radical scavenging capacity with 50% inhibitory concentration (IC(50)) of 3.48 ± 0.218 μg/mL and 10.84 ± 0.125 μg/mL and vitamin C equivalents of 0.351 g and 1.09 g for McConnell's Blue and Tuscan Blue, respectively. Cytotoxicity was measured using XTT (Sodium 3'-[1-(phenyl amino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitro] benzene sulfonic acid hydrate) colorimetric assay. Only L. nobilis and O. vulgare exhibited pronounced effects on the HeLa cell line. Dose-dependent studies revealed IC(50) of 34.46 ± 0.48 μg/mL and 126.3 ± 1.00 μg/mL on the HeLa cells and on the Vero cells 124.1 μg/mL ± 18.26 and 163.8 μg/mL ± 2.95 for L. nobilis and O. vulgare, respectively. Light (eosin and haematoxylin staining) and confocal microscopy (Hoechst 33342, acridine orange, and propidium iodide staining) were used to evaluate the cytotoxic mechanism of action for L. nobilis and O. vulgare.
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T47D and MCF7 are two human hormone-dependent breast cancer cell lines which are widely used as experimental models for in vitro and in vivo (tumor xenografts) breast cancer studies. Several proteins involved in cancer development were identified in these cell lines by proteomic analyses. Although these studies reported the proteomic profiles of each cell line, until now, their differential protein expression profiles have not been established. Here, we used two-dimensional gel and mass spectrometry analyses to compare the proteomic profiles of the two cell lines, T47D and MCF7. Our data revealed that more than 164 proteins are differentially expressed between them. According to their biological functions, the results showed that proteins involved in cell growth stimulation, anti-apoptosis mechanisms and cancerogenesis are more strongly expressed in T47D than in MCF7. These proteins include G1/S-specific cyclin-D3 and prohibitin. Proteins implicated in transcription repression and apoptosis regulation, including transcriptional repressor NF-X1, nitrilase homolog 2 and interleukin-10, are, on the contrary, more strongly expressed in MCF7 as compared to T47D. Five proteins that were previously described as breast cancer biomarkers, namely cathepsin D, cathepsin B, protein S100-A14, heat shock protein beta-1 (HSP27) and proliferating cell nuclear antigen (PCNA), are found to be differentially expressed in the two cell lines. A list of differentially expressed proteins between T47D and MCF7 was generated, providing useful information for further studies of breast cancer mechanisms with these cell lines as models.
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In Jordan, the leaves of Laurus nobilis (Family Lauraceae) have been used in folk medicine for the treatment of diarrhea, among other ailments. However, the ethnopharmacology of this plant needs to be scientifically validated. The present work was carried out to evaluate the scientific basis of the antidiarrheal effect of the aqueous extract of L. nobilis leaf. L. nobilis leaf extract significantly inhibited castor oil-induced diarrhea (effective concentration producing 50% of the maximum response [EC(50)]=150±6.4 mg/kg) and reduced castor oil-induced enteropooling in rats (EC(50)=162±5.9 mg/kg). The extract also significantly inhibited intestinal transit of a charcoal meal and exerted a significant dose-dependent relaxation (EC(50)=71±5.3 mg/mL) on rat ileal smooth muscle. The aqueous extract tested positive for flavonoids, alkaloids, and tannins. These results established the efficacy of L. nobilis leaf aqueous extract as an antidiarrheal agent and are consistent with the popular use of the plant in the treatment of gastrointestinal disorders, particularly diarrhea.
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The antioxidant and antiproliferative activities of the essential oils from Laurus nobilis leaves and seeds in relation to their composition were analysed. The most abundant components of the leaf essential oil were 1,8-cineole, 1-p-menthen-8-ethyl acetate, linalool and sabinene, while the seed oil was characterised by β-ocimene, 1,8-cineole, α-pinene and β-pinene as main constituents. Both seed and leaf essential oils exhibited a scavenging effect on the DPPH radical, with IC₅₀ values of 66.1 and 53.5 µg mL⁻¹, respectively. The leaf essential oil showed the strongest antioxidant activity in the β-carotene/linoleic acid system, with an IC₅₀ value of 35.6 µg mL⁻¹ after 30 min of incubation. Both leaf and seed oils inhibited proliferation of the K562 tumour cell line with IC₅₀ values of 95 and 75 µg mL⁻¹, respectively. The L. nobilis leaf oil showed a percentage of erythroide differentiation of 15% at a concentration of 10 µg mL⁻¹. A value of 12% was found for the seed essential oil at a concentration of 50 µg mL⁻¹. When the oils were added to a suboptimal concentration of the commercial drug, cytosine arabinoside, a clear synergic effect was observed.
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The health-promoting effects of natural phenolic compounds are attracting growing interest. In this study, we tested four plant extracts, namely basil, juniper, laurel and parsley, and two well-known pure phenolic compounds of natural origin, curcumin and resveratrol, for their possible cytotoxic effects in vitro. AraC was used as an apoptotic reference compound. The pure compounds were studied in two cell lines, SH-SY5Y neuroblastoma and CV1-P fibroblast cells, and the plant extracts in SH-SY5Y cells. Cytotoxicity was examined by MTT and LDH assays, and the molecular mechanisms by Western blot analysis of p53 protein in cells. Juniper extract decreased the cell viability and increased the amount of p53 in SH-SY5Y cells at lower concentrations than did other plant extracts, and its effects on the amount of p53 in cells were comparable to the treatment with 50μM AraC. The actions of curcumin and resveratrol were dependent on the concentration and cell line. Curcumin decreased the cell viability and increased the amount of p53 in SH-SY5Y cells more effectively than in CV1-P cells. The comparison between the results of AraC and pure curcumin showed a similar effect on the amount of p53. Our results indicate a potential role of plant extracts and plant-derived compounds as health-promoting food constituents, as well as candidates for drug development.
Three new compounds, isolated from the fruits of Laurus nobilis, have been characterized as 10-hydroxyoctacosanyl tetradecanoate [1], 1-docosanol tetradecanoate [3], and 11-hydroxytriacontan-9-one [4].
A new sesquiterpene, lauroxepine and six known sesquiterpene lactones, were obtained through bioactivity-directed isolation from a methanol extract of the fruits of Laurus nobilis. The hexane-soluble part of the methanol extract yielded lauroxepine, costunolide and gazaniolide, while the dichloromethane-soluble part of the methanol extract afforded costunolide and four other sesquiterpene lactones including santamarine, reynosin, 11,13-dehydrosantonin and spirafolide. The new sesquiterpene lauroxepine and spirafolide have a rare molecular structure carrying an oxepine ring. Structures of the compounds were determined through 1D and 2D NMR and mass (EI-MS) techniques. The extracts were investigated for both ovarian cytotoxic activity and DNA damaging properties against three yeasts. Among the three tested extracts prepared from flowers, leaves and fruits of L. nobilis, the most cytotoxic active extract against ovarian cancer cell line was found to be the fruit extract with 98% inhibition. Among all tested extracts, only the fruit extract showed marginal inhibition (63.2%) against one DNA repair-deficient yeast strain (pRAD52 Gal). Six known sesquiterpene lactones were found to be highly cytotoxic against the A2780 ovarian cancer cell line, however, lauroxepine was not found to be active in A2780.