PHCOG MAG.

ORIGINAL ARTICLE

Protective effects of bioactive phytochemicals from

Mentha piperita with multiple health potentials
Seyedeh Maryam Sharafi, Iraj Rasooli1, Parviz Owlia2, Massoud Taghizadeh,
Shakiba Darvish Alipoor Astaneh
Department of Biology, Shahed University, Tehran-Qom Express Way, Opposite Imam Khomeini's shrine, Tehran-3319118651, 1Medicinal Plants
Research Center, Shahed University, Tehran-Qom Express Way, Opposite Imam Khomeini's shrine, Tehran-3319118651, 2Faculty of Medicine,
Shahed University, P.O.Box 14155-7435, Tehran, Iran

Submitted: 12-02-2010 Revised: 26-03-2010 Published: 30-07-2010

ABSTRACT
Mentha piperita essential oil was bactericidal in order of E. coli> S. aureus > Pseudomonas aeruginosa> S. faecalis >
Klebsiella pneumoniae. The oil with total phenolics of 89.43 ± 0.58 μg GAE/mg had 63.82 ± 0.05% DPPH inhibition activity
with an IC50 = 3.9 μg/ml. Lipid peroxidation inhibition was comparable to BHT and BHA. A 127% hike was noted in serum
ferric-reducing antioxidant power. There was 38.3% decrease in WBCs count, while platelet count showed increased levels
of 214.12%. Significant decrease in uric acid level and cholesterol/HDL and LDL/HDL ratios were recorded. The volatile oil
displayed high cytotoxic action toward the human tumor cell line. The results of this study deserve attention with regard
to antioxidative and possible anti-neoplastic chemotherapy that form a basis for future research. The essential oil of mint
may be exploited as a natural source of bioactive phytopchemicals bearing antimicrobial and antioxidant potentials that
could be supplemented for both nutritional purposes and preservation of foods.
Key words: Antioxidant, antibacterial, cytotoxicity, cancer, Mentha piperita

INTRODUCTION (PG) have been added to lipid-containing foods.[2] However,

potential health hazards of synthetic antioxidants in foods,
Supplementation of human diet with herbs, containing including possible carcinogens, have been reported several
especially high amounts of compounds capable of times.[3] Antioxidants are compounds that can delay,
deactivating free radicals, besides the fruits and vegetables inhibit, or prevent the oxidation of oxidizable matters by
recommended as optimal sources of antioxidant activity, scavenging free radicals and diminishing oxidative stress.
may have beneficial effects. The benefits resulting from Plants contain a wide variety of antioxidant phytochemicals
the use of natural products rich in bioactive substances or bioactive molecules, which can neutralize the free
have promoted the growing interest of pharmaceutical, radicals and thus retard the progress of many chronic
food and cosmetic industries as well as of individual diseases associated with oxidative stress and reactive oxygen
consumers in the quality of herbal products. The oxidative species (ROS). The intake of natural antioxidants has been
deterioration of lipids is of great concern in the shelf life associated with reduced risk of cancer, cardiovascular
of foods. Lipid peroxidation leads to development of disease, diabetes and diseases associated with ageing.
undesirable off-flavors and decreases the acceptability of Studies on dietary free radical scavenging molecules
foods. In addition, lipid oxidation decreases food safety have attracted the attention to characterize phenolic
and nutritional quality by the formation of potentially toxic compounds and other naturally occurring phytochemicals
products and secondary oxidation products during cooking as antioxidants.[4] Spices and herbs are generally applied
or processing.[1] To prevent and retard lipid oxidation, to food which is a nutrient rich environment for most
synthetic antioxidants such as butylated hydroxyanisole bacteria. The antibacterial activity, however, could be
(BHA), butylated hydroxytoluene (BHT) and propyl gallate also used in nutrient poor environments, for example,
cleaning of food processing devices and depuration of
Address for correspondence: shellfish.[5] A variety of molecules derived from spice
Dr. Iraj Rasooli, Medicinal Plants Research Center, Shahed
University, Tehran-Qom Express Way, Opposite Imam Khomeini's
possess bioactive properties. Spices are also considered as
shrine, Tehran-3319118651, Iran. E-mail: rasooli@shahed.ac.ir nutraceuticals in view of their nutritional, medicinal and
therapeutical properties. In addition to improving flavor,
DOI: 10.4103/0973-1296.66926 certain spices and essential oils prolong the storage life

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 Sharafi, et al.: Protective phytochemicals from Mentha piperita

of foods by an antimicrobial activity. Spices are primarily (BHI+DMSO) and one sterility control (BHI+DMSO+test
used in the food industry for improving the quality of the oil). Plates were incubated under normal atmospheric
product. These powdered spices suffer disadvantages, e.g. conditions, at 37oC for 24 h. The contaminating bacterial
quality variations from batch to batch caused by uneven growth, if at all, was indicated by the presence of a white
distribution of flavor, loss of flavor strength, quality ‘‘pellet’’ on the well bottom.
during storage, insect infestation, bacterial contamination,
unhygienic nature and inconveniency in bulk handling. To Oil dilution solvent
overcome these problems, spice essential oil has come 5 μl of dimethylsulphoxide (DMSO) loaded on sterile blank
into use in the food industries.[6] Food-borne illness caused disks were placed on Mueller Hinton agar plates streaked
by consumption of contaminated foods with pathogenic with suspensions of bacterial strains, and were then
bacteria and/or their toxins has been of great concern incubated at 37oC for 24 hours. There was no antibacterial
to public health. Controlling pathogenic microorganisms activity on the plates and hence DMSO was selected as a
would reduce food-borne outbreaks and assure consumers safe diluting agent for the oil. 10 μl from each oil dilution
a continuing safe, wholesome and nutritious food supply.[7,8] was added to sterile blank discs. The solvent also served
The exploration of naturally occurring antimicrobials as control.
for food preservation receives increasing attention
due to consumer awareness of natural food products Disc diffusion method
and a growing concern of microbial resistance toward The agar disc diffusion method was employed for the
conventional preservatives.[9] Bearing in mind the growing determination of antimicrobial activities of the essential
use of essential oils, their genotoxicity testing, identification oils in question. Briefly, 0.1 ml from 108 CFU/ml bacterial
of genotoxic compounds and attempts to improve their suspension was spread on the Mueller Hinton Agar
safety may be important fields of future research. Mentha (MHA) plates. Filter paper discs (6 mm in diameter) were
piperita (Peppermint) is globally and widely used in the impregnated with 10 μl of the undiluted oil and were placed
forms of oil, extract, leaves, and water. However, very little on the inoculated plates. These plates, after remaining at
information is available on physiological, pharmacological 4oC for 2h, were incubated at 37oC for 24 h. The diameters
and cytotoxic properties of Mentha piperita essential oil. of the inhibition zones were measured in millimeters. All
Therefore, the present investigation was undertaken to tests were performed in triplicate.
evaluate the protective activity of bioactive phytochemicals
Radical scavenging capacity of the oils
from M. piperita essential oil.
The hydrogen atom or electron donation abilities of
the corresponding extracts and some pure compounds
MATERIALS AND METHODS were measured from the bleaching of the purple-colored
methanol solution of 2,20-diphenylpicrylhydrazyl
Equipments and chemicals (DPPH). 50 μl of 1:5 concentrations of the essential
T he major equipments used were UV-2501PC oil in methanol was added to 5 ml of a 0.004% methanol
spectrophotometer, ELISA reader and routine microbiology solution of DPPH. Trolox (1 mM) (Sigma-Aldrich), a
laboratory equipments. The essential oil was purchased stable antioxidant, was used as a synthetic reference. After
from Zardband company, Tehran, Iran. Microbial and cell a 30 min incubation period at room temperature, the
culture media and laboratory reagents were from Merck, absorbance was read against a blank at 517 nm. Inhibition
Germany. Other chemicals were of analytical grade. of free radical by DPPH in percent (I%) was calculated in
the following way:
Microbial strain and growth media I% = (Ablank ─ Asample/Ablank) × 100;
E. coli (ATCC 25922), S. aureus (ATCC 25923), Streptococcus
fecalis (PTCC 33186), Pseudomonas aeruginosa (ATCC 8830) where Ablank is the absorbance of the control reaction
and Klebsiella pneumoniae (ATCC 13883) were employed in (containing all reagents except the test compound), and
the study. Bacterial suspensions were made in brain heart Asample is the absorbance of the test compound. Tests were
infusion (BHI) broth to a concentration of approximately carried out in triplicate.
108 cfu/ml. Subsequent dilutions were made from the
above suspension, which were then used in the tests. Lipid peroxidation (LPO) assay
Approximately 10 mg of β-carotene (type I synthetic,
Oil sterility test Sigma–Aldrich) was dissolved in 10 ml of chloroform. The
To ensure sterility of the oils, geometric dilutions ranging carotene-chloroform solution, 0.2 ml, was pipetted into a
from 0.036 to 72.0 mg/ml of the essential oil were prepared boiling flask containing 20 mg linoleic acid (Sigma–Aldrich)
in a 96-well microtitre plate, including one growth control and 200 mg Tween 40 (Sigma– Aldrich). Chloroform was

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 Sharafi, et al.: Protective phytochemicals from Mentha piperita

removed using a rotary evaporator at 40oC for 5 min and plexus. The blood samples collected on day 0 and day 30
to the residue, 50 ml of distilled water was added, slowly were used for determining red cell and leucocyte counts
with vigorous agitation, to form an emulsion. 5 ml of the and for hemoglobin, hematocrit and biochemical parameter
emulsion was added to a tube containing 200 µl of essential analysis. The serum concentrations of urea, creatinine,
oils solution and the absorbance was immediately measured glutamic-oxalacetic transaminase (GOT) and glutamic-
at 470 nm against a blank, consisting of an emulsion pyruvic transaminase (GPT) and other parameters were
without β-carotene. The tubes were placed in a water bath determined by using commercial kits. The values obtained
at 50oC and the oxidation of the emulsion was monitored were compared within and between the groups.
spectrophotometrically by measuring absorbance at 470
nm over a 60 min period. Control samples contained 10 Ferric reducing antioxidant power of serum (FRAP)
µl of water instead of essential oils. Butylated hydroxy The antioxidant power of blood serum was determined
anisole (BHA) and butylated hydroxytoluene (BHT), using FRAP assay.[11] Briefly, 50 μl of the blood serum
stable antioxidants, were used as synthetic references. The (normal as well as experimental cells) suspension was
antioxidant activity was expressed as inhibition percentage added to 1.5 ml of freshly prepared and pre-warmed (37
with reference to the control after 60 minutes incubation o
C) FRAP reagent (300 mM acetate buffer, pH = 3.6, 10
using the following equation: AA = 100(DRC─DRS)/DRC, mM TPTZ (tripyridyl-s-triazine) in 40 mM HCl and 20
where AA = antioxidant activity; mM FeCl3.6H2O in the ratio of 10:1:1) and incubated at
DRC = degradation rate of the control = [ln(a/b)/60]; 37 oC for 10 min. The absorbance of the sample was read
DRS = degradation rate in the presence of the sample = against reagent blank (1.5 ml FRAP reagent + 50 μl distilled
[ln(a/b)/60]; water) at 593 nm. Aqueous solutions of known Fe(II)
a = absorbance at time 0; concentration (FeSO4.7H2O) were used for calibration of
b = absorbance at 60 min. the FRAP assay and antioxidant power was expressed as
µg/ml (y = 0.0025x+0.0005; r2 = 0.9976).
Total phenolic content assay
Total phenol content was estimated as gallic acid equivalents Cytotoxicity assay
(GAE; μg gallic acid/mg extract) as described earlier.[10] In The human cervical carcinoma Hela cell line NCBI
brief, a 100 μl aliquot of dissolved extract was transferred code No. 115 (ATCC number CCL-2) were obtained
to a 10 ml volumetric flask, containing ca. 6.0 ml H2O, from Pasteur Institute, Tehran-Iran. The cells were
to which was subsequently added 500 μl Folin–Ciocalteu grown in RPMI 1640 supplemented with 10% fetal
reagent. After 1 min, 1.5 ml 200 g/l Na2CO3 was added calf serum, 1% (w/v) glutamine, 100 U/ml penicillin
and the volume was made up to 10 ml with H2O. After and 100 μg/ml streptomycin. Cells were cultured in a
2 h of incubation at 25°C, the absorbance was measured humidified atmosphere at 37 °C in 5% CO2. Cytotoxicity
at 760 nm. Gallic acid (Sigma Co., 0.2–1 mg/ml gallic acid) was measured using a modified MTT assay. This assay
was used as the standard for the calibration curve, and detects the reduction of MTT [3-(4,5-dimethylthiazolyl)-
the total phenolic contents were expressed as mg gallic 2,5-diphenyltetrazolium bromide] by mitochondrial
acid equivalents per gram of tested extracts (Y=0.001x dehydrogenase, to blue formazan product, which reflects
+0.0079; r2 = 0.997). the normal functioning of mitochondrial and cell viability.[12]
Briefly, the cells (5 × 104) were seeded in each well
Acute and subchronic toxicity containing 100μl of the RPMI medium supplemented
A 30-day oral toxicity study was conducted in Wistar rats with 10% FBS in a 96-well plate. After 24 h of adhesion,
(Rattus norvegicus; 180–200 g) to determine the potential of a serial of doubling dilution of the essential oil was added
C. cyminum essential oil to produce toxic effects. The rats of to triplicate wells over the range of 1.0–0.005 μl/ml. The
both sexes were housed in temperature-controlled rooms final concentration of ethanol in the culture medium was
and were given food and water ad libitum until used. For the maintained at 0.5% (volume/volume) to avoid toxicity
acute toxicity analysis, the essential oil was administered of the solvent.[13] After 2 days, 10 μl of MTT (5 mg/ml
via oral gavage to the rats (n = 10 mice per group) at stock solution) was added and the plates were incubated
doses ranging from 100 to 2000 mg/kg/day. The results for an additional 4 h. The medium was discarded and the
obtained were compared with those for the control animals formazan blue, which formed in the cells, was dissolved
[3% (v/v) Tween 80 in saline]. The LD50 was calculated with 100 μl dimethyl sulphoxide (DMSO). The optical
by the probit method by using SPSS 7.0 for Windows. To density was measured at 490 nm using a microplate ELISA
investigate the subchronic toxicity of the essential oil, after reader. The cell survival curves were calculated from cells
30 days of oral administration to rats, the hematological incubated in the presence of 0.5% ethanol. Cytotoxicity
and serum biochemistry parameters were evaluated. Blood is expressed as the concentration of drug inhibiting cell
samples were collected by puncture in the infraorbital growth by 50% (IC50), (y = 110.12x0.025; r2 = 0.9981). All

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 Sharafi, et al.: Protective phytochemicals from Mentha piperita

tests and analyses were run in triplicate and mean values

were recorded.

Statistical analysis
All the experimental data are presented as mean ±
SEM of three individual samples. Data are presented
as percentage of free radical scavenging/inhibition lipid
peroxidation on different concentrations of cumin oil.
IC50 (the concentration required to scavenge 50% of free
radicals) value was calculated from the dose-response
curves. Antibacterial effect was measured in terms of
zone of inhibition to an accuracy of 0.1 mm and the
effect was calculated as a mean of triplicate tests. All of
the statistical analyses were performed with the level of
significant difference between compared data sets being Figure 1: Antimicrobial activity of Mentha piperita essential oil
set at P < 0.05.

RESULTS AND DISCUSSION

The antibacterial effect of Mentha piperita was tested

against some bacteria by agar diffusion method. All the
test organisms were sensitive to the oil with the sensitivity
order of E.coli> S. aureus > Pseudomonas aeruginosa> S.faecalis
> Klebsiella pneumoniae [Figure 1]. The antimicrobial activity
of various essential oils including mint (Mentha piperita)
was evaluated on survival and growth of different strains
of E. coli O157:H7. The strains of E. coli exhibited similar
susceptibilities to the action of the essential oils assayed
at the inhibition zone diameter range of 16-19mm.[14]
Addition of mint essential oil reduced the total viable Figure 2: Lipid peroxidation activity of Mentha piperita essential oil
counts of S. aureus about 6–7 logs.[15] Our results seem to
be consistent with the above reports. Since essential oils
consist of terpenes (phenolics in nature), it would seem Table 1: Total phenolics and mean inhibition
of DPPH free radical (%) by Mentha piperita
reasonable that their mode of action might be related to
essential oil dilutions
those of other phenolic compounds.[15] Mentha extract (ME)
has been reported to have antioxidant and antiperoxidant Oil (µg/ml) and DPPH GAE
synthetic antioxidants inhibition μg Gallic acid/mg
properties. [16] Hence we attempted to evaluate these (%) sample
properties with the essential oil under study. The oil showed 10 63.82 ± 0.05 89.43 ± 0.58
at its maximum 63.82 ± 0.05% inhibition of DPPH activity 5 55.85 ± 0.09 40.43 ± 0.58
with an IC50 = 3.9 μg/ml [Table 1]. The extracts of the 2.5 42.77 ± 0.09 15.10 ± 1
M. piperita has shown 93.9 ± 1.68% inhibition of DPPH 0.2 26.50 ± 0.45 9.43 ± 0.58
activity with an IC50 = 273 μg/ml.[17] In another study the BHT 1mM 9.63 __
BHA 1mM 15.28 __
essential oils of M. piperita had an IC50 = 2.53 µg/ml in the
Trolox 1mM 99.62 __
DPPH assay.[18] Total phenolics of M. piperita were 89.43 ±
0.58 μg GAE/mg [Table 1]. Plant phenols and flavonoids
are known to inhibit lipid peroxidation by quenching lipid Table 2: Blood serum Ferric-reducing
peroxy radicals and reduce or chelate iron in lipoxygenase antioxidant power (FRAP) of Mentha piperita
enzyme and thus prevent initiation of lipid peroxidation essential oil
reaction.[19] The antioxidant capacities of the essential oil Serum FRAP FeSO4.7H2O Test/control
as assessed by different assay methods are summarized equivalent ratio
in Table 2 and Figure 2. Lipid peroxidation inhibition by (μg/ml) (%)

M. Piperita oil was statistically (P>0.05) at the same level Control 226.25 ± 5.84 100
Mentha piperita 287.4 ± 4.46 127
of the synthetic antioxidant BHT and lower (P<0.001)

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 Sharafi, et al.: Protective phytochemicals from Mentha piperita

than BHA [Figure 2]. Many different methods have as compared to the control group [Table 2]. The antioxidant
been established for evaluating the antioxidant capacity activity can be correlated to the moderate phenolic
of certain biological samples, with such methods being content of the oil. The phenolic content of certain spices
classified, roughly, into one of two categories based upon appears to correlate well with such spices’ protective effect
the nature of the reaction that the method involved.[20] against peroxynitrite-mediated tyrosine nitration and lipid
The methods involving an electron-transfer reaction peroxidation. Such an observation indicates that phenolics
include the total phenolics assay using Folin–Ciocalteu present in the spices contributed to such spice-elicited
reagent, the TEAC and the DPPH radical-scavenging protection against peroxynitrite toxicity.[22] There were
assay. The radical scavenging effect of M. piperita essential some treatment-related effects in hematology parameters
oil was found to be 6.6 and 4.17 times more potent than [Table 3]. Although the animals gained significant weight but
the standard BHT and BHA respectively, but less potent the weight gain was statistically (P=0.1) insignificant. There
(64%) than Trolox [Table 1]. This suggests that M. piperita was 38.3% decrease in WBCs count, while platelet count
essential oil is a good free radical scavenger or hydrogen showed increased levels of 214.125% [Table 3]. Clinical
donor and contributes significantly to the antioxidant chemistry parameters showed significant decrease in uric
capacity of M. piperita. The DPPH radical scavenging acid level while total cholesterol and triglycerides levels
is a sensitive antioxidant assay and is independent of increased significantly. The interesting observations were
substrate polarity.[21] DPPH is a stable free radical that of increased good cholesterol (HDL) level that reduced
can accept an electron or hydrogen radical to become cholesterol/HDL and LDL/HDL ratios to 80% and
a stable diamagnetic molecule. A significant correlation 45.93% respectively. Thus, M. piperita with a high phenolic
was shown to exist between the phenolic content and content and good antioxidant activity can be supplemented
with DPPH scavenging capacity for each spice.[22] Ferric- for both nutritional purposes and preservation of foods.
reducing antioxidant power in the blood sera of the rats Recently Dragland et al.[23] speculated that the daily intake
gavaged with a daily dose of 100 µl oil showed 127% hike of 1 g of various potent antioxidant spices makes a

Table 3: Mean hematology and clinical chemistry values of rats blood samples fed with Mentha piperita
essential oil
Parameters Control Mean value (test) % change P value
Initial body weight (g) 142.50±2.9 159±3.61 111.58 0.001
Final body weight (g) 157.50±5 198.33±18.93 125.93 0.008
Weight gain (%) 110.53±2 124.95±14.73 114.42 0.106
Erythrocyte count (RBC) (×106/lL) 7.23±1.25 7.90±0.59 109.39 0.430
Total white blood cell (WBC) and differential 9400±668 5800±608 61.7 0.0008
leukocyte count (×103/µl)
Hemoglobin concentration (HGB) (g/dl) 12.78±1.4 13.53±0.51 105.94 0.434
Hematocrit (HCT) (%) 39.63±1.7 38.5±0.60 97.16 0.338
Platelet count (PLT) (×103/µl) 238500±1658 510666.67±5401.34 214.12 0.0002
Red cell distribution width [RDW (%)] 14.75±2.14 13.97±1.29 94.69 0.602
Mean platelet volume (MPV) 7.600.56 7.07±0.45 92.98 0.236
Mean corpuscular volume (MCV) (fL) 52.93±3.84 50.6±4 95.61 0.471
Mean corpuscular hemoglobin (MCH) (pg) 17.78±1.37 17.33±0.71 97.52 0.638
Mean corpuscular hemoglobin concentration 33.75±1.95 35.47±0.81 105.09 0.217
[MCHC (g/dl)]
Fasting glucose (GLUC) (mg/dl) 221±7.79 218.33±15.18 98.79 0.77
Blood urea nitrogen (BUN) (mg/dl) 60±5.96 55.23±5.25 92.06 0.322
Blood creatinine (CREA) (mg/dl) 0.64±0.1 0.63±0.10 99.21 0.95
Uric acid 8.18±2.45 4.29±0.85 52.44 0.049
Total cholesterol(CHOL) (mg/dl) 75.75±1 91±1 120.13 0.0000
Triglycerides (TRIG) (mg/dl) 45±9.2 73±8.19 162.22 0.009
HDL 45.50±4 67.30±0.72 147.91 0.0003
LDL 15.05±1.9 10.20±1.71 67.77 0.018
Cholesterol/HDL ratio 1.68±0.16 1.35±0.03 80.71 0.021
LDL/HDL ratio 0.33±0.03 0.15±0.03 45.93 0.0003
SGOT 530.75±68 520.67±69.41 98.10 0.855
SGPT 236.75±9 146.33±16.5 61.81 0.031
Alkaline phosphatase (ALKP) (U/L) 136.75±3 244.67±84.79 178.92 0.063

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relevant contribution to the total intake of antioxidants the relationship of cytotoxicity with antioxidant activity.[29]
in a normal diet. Peppermint oil was minimally toxic in Although all in vitro experiments hold limitations with
acute oral studies. Short-term and subchronic oral studies regard to possible in vivo efficacy, the results of this study
reported cyst-like lesions in the cerebellum in rats that deserve attention with regard to antioxidative and possible
were given doses of peppermint oil containing pulegone, anti-neoplastic chemotherapy that form a basis for future
pulegone alone, or large amounts (>200 mg/kg/day) of research. Even though essential oils might not be ideal for
menthone. With the limitation that the concentration the treatment of human cancers, the oil tested certainly
of pulegone in these ingredients should not exceed deserves some further investigation.
1%, it was concluded that Mentha piperita (peppermint)
oil, Mentha piperita (peppermint) extract, Mentha piperita
(peppermint) leaves, Mentha piperita (peppermint) water are
CONCLUSION
safe as used in cosmetic formulations.[24] At a concentration
From the above results, it can be concluded that the tested
of 0.02 µl/ml, oil destructed Hela cells by 98.48%
essential oil exhibited antimicrobial activity against the tested
[Table 4]. At lower doses, the oil was still toxic to the cells.
microorganisms and it could be a better natural antioxidant.
The volatile oil displayed an excellent cytotoxic action
The essential oil provided comparable antioxidative activity
toward the human tumor cell line. The IC50 was calculated
as compared with synthetic antioxidants, which provides
to be 1×10-16 which seem to be indicative of high toxicity
a way of screening antioxidants for foods, cosmetics and
of the oil that needs testing with normal healthy cells in
medicine. Hence, the essential oil of mint may be exploited
order to rule out its hazardous cytotoxicity before it is
as a natural source of bioactive phytopchemicals bearing
recommended for use. The oral administration of Mentha
antimicrobial and antioxidant potentials.
piperita extract (ME) showed a significant reduction in the
number of lung tumors from an incidence of 67.92%
in animals given only benzo[a]pyrene (BP) to 26.31%. ACKNOWLEDGEMENTS
Cancer chemoprevention is defined as the use of chemicals
or dietary components to block, inhibit, or reverse the The authors wish to thank Medicinal Plants Research Centre of
development of cancer in normal or preneoplastic tissue. Shahed University (Tehran-Iran) for the sanction of research
A large number of potential chemopreventive agents grants to conduct the present study.
have been identified, and they function by mechanisms
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Pharmacognosy Magazine | Jul-Sep 2010 | Vol 6 | Issue 23 153