ArticlePDF Available


Natural products have been studied aiming to understand their biological properties. Thus, this study aimed to investigate the antimicrobial activity of twenty-seven essential oils (EOs) used in aromatherapy procedures, a natural therapy with great emphasis currently used against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa strains. The agar dilution method was carried out and minimal inhibitory concentration against 50% and 90% of strains (MIC50% and MIC90% values) were reported. The S. aureus strains were highly susceptible with MIC90% from 0.21 mg/mL to black pepper (Piper nigrum) and tea tree (Melaleuca alternifolia) to 26.52 mg/mL with copaiba (Copaifera officinalis) EO. Cinnamon (Cinnamomum cassia) and clove (Syzygium aromaticum) EOs were effective against E. coli (2.0 mg/mL) while the S. aromaticum EO was against P. aeruginosa (8.29 mg/mL). Thus, the higher susceptibility of Gram-positive bacteria when compared with Gram-negative strains was found, and a large variability in the potential antibacterial has also been observed.
This article was downloaded by: [UNESP]
On: 03 December 2013, At: 03:36
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,
37-41 Mortimer Street, London W1T 3JH, UK
Journal of Essential Oil Research
Publication details, including instructions for authors and subscription information:
Antimicrobial activity of essential oils
Bruna Fernanda Murbach Teles Andradea, Lidiane Nunes Barbosaa, Isabella da Silva Probsta &
Ary Fernandes Júniora
a Department of Microbiology and Immunology, Institute of Biosciences, Universidade
Estadual Paulista Júlio de Mesquita Filho-UNESP, São Paulo, Brazil
Published online: 29 Nov 2013.
To cite this article: Bruna Fernanda Murbach Teles Andrade, Lidiane Nunes Barbosa, Isabella da Silva Probst & Ary
Fernandes Júnior (2014) Antimicrobial activity of essential oils, Journal of Essential Oil Research, 26:1, 34-40, DOI:
To link to this article:
Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained
in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no
representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the
Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and
are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and
should be independently verified with primary sources of information. Taylor and Francis shall not be liable for
any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever
or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of
the Content.
This article may be used for research, teaching, and private study purposes. Any substantial or systematic
reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any
form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://
Antimicrobial activity of essential oils
Bruna Fernanda Murbach Teles Andrade, Lidiane Nunes Barbosa, Isabella da Silva Probst and
Ary Fernandes Júnior*
Department of Microbiology and Immunology, Institute of Biosciences, Universidade Estadual Paulista Júlio
de Mesquita Filho-UNESP, São Paulo, Brazil
(Received 11 July 2012; accepted 17 October 2013)
Natural products have been studied aiming to understand their biological properties. Thus, this study aimed to
investigate the antimicrobial activity of twenty-seven essential oils (EOs) used in aromatherapy procedures, a natural
therapy with great emphasis currently used against Staphylococcus aureus,Escherichia coli and Pseudomonas
aeruginosa strains. The agar dilution method was carried out and minimal inhibitory concentration against 50% and
90% of strains (MIC
and MIC
values) were reported. The S.aureus strains were highly susceptible with
from 0.21 mg/mL to black pepper (Piper nigrum) and tea tree (Melaleuca alternifolia) to 26.52 mg/mL with
copaiba (Copaifera ofcinalis) EO. Cinnamon (Cinnamomum cassia) and clove (Syzygium aromaticum) EOs were
effective against E.coli (2.0 mg/mL) while the S.aromaticum EO was against P.aeruginosa (8.29 mg/mL). Thus,
the higher susceptibility of Gram-positive bacteria when compared with Gram-negative strains was found, and a large
variability in the potential antibacterial has also been observed.
Keywords: antibacterial; aromatherapy; EO; minimal inhibitory concentration
Herbs, and their essential oils (EOs), have been used
since the beginning of human history for avored foods
and beverages; they have been empirically used to dis-
guise unpleasant odors, attract other individuals and
control health problems, contributing to the welfare
humans and animals, thus demonstrating the cultural
and economic importance use of these products (1).
The EOs are typically liquid, clear and unusually
colored, complex and the present compounds are vola-
tile, characterized by a strong odor and synthesized by
aromatic plants during secondary metabolites, which
act to protect the plant against microorganisms and
insects. They can be synthesized in several plant organs
such as buds, owers, leaves, stems, branches, seeds,
berries, roots, wood or bark, being stored in secretory
cells, cavities, channels, epidermal cells or trichomes
(2). Temporal and spatial variations in the total content
of secondary metabolites products from plants occur at
different levels and, despite the existence of a genetic
control, the expression may undergo changes resulting
from biochemical, physiological, ecological and evolu-
tionary interactions that represent an important interface
between chemistry and the environment surrounding
the plants (3).
As for industrial production, EOs are obtained by
steam distillation, which is on the rise in food and
pharmaceutical applications, and pressurized supercriti-
cal uid, especially carbon dioxide (4).
EOs have several biological properties, such as lar-
vicidal action (5), antioxidant (6), analgesic and anti-
inammatory (7), fungicide (8) and antitumor activity
The in vitro antimicrobial activity of EO has been
researched extensively against a variety of microorga-
nisms (10). Nevertheless, the emergence of multidrug-
resistant bacteria poses a challenge to treating infections,
so the need to nd new substances with antimicrobial
properties for use in the ght against these microorga-
nisms is evident (11,12). Historically, most antibiotics
come from a small set of functional molecular structures
whose lives were extended by generations of synthetic
reorganizations and arrangements (13). Moreover, the
food, pharmaceutical and cosmetic industries have
shown great interest in the antimicrobial properties of
EOs, as the use of natural additives has received
importance as a trend in the replacement of synthetic
preservatives (14).
The objective was to establish in vitro the antimi-
crobial activities of EOs that are normally used in natu-
ral therapies against S.aureus,E.coli and
P.aeruginosa strains isolated from human clinical
specimens and one standard ATCC (American Type
Culture Collection) of each bacterial species; this was
*Corresponding author. Email:
© 2013 Taylor & Francis
Journal of Essential Oil Research, 2014
Vol. 26, No. 1, 3440,
Downloaded by [UNESP] at 03:36 03 December 2013
Table 1. Density (mg/mL) and essential oils chemical compounds (%) obtained by chromatographymass spectrometry
(GCMS) from the supplier of the essential oils (By Samia Aromatherapy/São Paulo/Brazil).
Essential oil
(mg/mL) Compounds in essential oils (%)
Bergamot (Citrus
aurantium bergamia)
871 Limonene (35.24), linalina acetate (30.40), linalool (18.45), β-pinene (5.42),
γ-terpinene (3.74), sabinene (0.92), α-pinene (0.89), myrcene (0.81), for-cymene (0.45)
Black pepper (Piper
846 Limoneno (23.80), δ-3-carene (21.97), α-pinene (12.89), β-caryophyllene (11.34),
β-pinene (3.91), sabinene (3.78), α-felandeno (3.76), myrcene (2.88), para-cymene
(1.38), linalool (1.24), terpinolene (1.17), β-selineno (1.11), 1.8 cineole (0.98), α-
terpinene (0.97), α-humulene (0.77), α-copaene (0.71), eugenol (0.56), terpinen-4-ol
(0.47), camphene (0.21), safrole (0.17)
Brazils spearmint (Mentha
849 Menthol (54.48), menthone (19:12), pulegone (5.57), isopulegol (2.02)
Cardamom (Elettaria
869 n/d
Cedar (Cedrus atlantica) 891 Widreno (27.75), α-cedrol (22.14), α-Cedrenus (19.84), α-muuroleno (4.55), widrol
Cinnamon (Cinnamomum
1008 Eugenol (72.13), eugenila acetate (3.87), β-caryophyllene (3.48), benzyl benzoate
(3.24), linalool (1.23), para-cymene (0.76), α-pinene (0.63), α-humulene (0.61),
α-phellandrene (0.49), 1.8 cineole (0.27), limonene (0.22), camphene (0.21), β-pinene
Clary sage (Salvia sclarea) 857 Linalina acetate (66.77), linalool (22.67), geranyl acetate (3.29), β-caryophyllene
(1.15), myrcene (0.18), limonene (0.15), 1.8 cineole (0.12)
Clove (Syzygium
988 Eugenol (83.63), β-caryophyllene (12.39), alpha-humulene (3.05), eugenol acetate
Copaiba (Copaifera
884 β-Caryophyllene (44.47), β-bisabolene (8.0), germacrene B (8.0), α-copaene (7.98),
germacrene d (5.95), α-humulene (5.40), δ-cadinene (4.57)
Cypress (Cupressus
840 α-Pinene (52.26), δ-3-carene, α-terpinolene (2.65), α-terpinila acetate (2.63), limonene
(2.60), myrcene (2.40), terpinen-4-ol (1.40), sabinene (1.24), β-pinene (1.14), α-tujeno
(0.96), α-fenchene (0.81), γ-terpinene (0.79), p-cymene (0.70), geranyl acetate (0.41),
α-terpinene (0.35), 1.8 cineole (0.34), camphene (0.28)
Eucalyptus (Eucalyptus
883 1.8 Cineole (80.17), α-pinene (11.25), diacetone alcohol (4.32), p-cymene (2.28),
α-terpineol (0.85), terpinen-4-ol (0.60), β-pinene (0.53)
Fennel (Foeniculum
919 trans-Anethole (95.66), linalool (2.91), estragol (0.39), α-pinene (0.13)
Geranium (Pelargonium
848 Citronellol (31.58), geraniol (25.47), fermiato of citronelita (12.74), fermiato of
geranyl (6.71), linalool (6.33); isomenthone (4.35), rose oxide (0.89), citronelita
acetate (0.48)
Ginger (Zingiber
850 α-Zingiberene (22.85), curcumene (18.96), β-sesquilandreno (13:12), β-bisabolene
(11.58), α-farnesene (4.28), camphene (1.77), β-phellandrene (1.58), 1.8 cineole (1.35),
α-pinene (0.43) trans-β-farnesene (0.30), myrcene (0.20)
Lavender (Lavandula
853 1.8 Cineole (45.97), p-cymene (4.19), 1-terpinen-4-ol (2.30), alpha-pinene (1.48),
limonene (1.46), gamma-terpinene (1.17), terpinolene (1.04)
Lemongrass (Cymbopogon
858 Geranial (48.57), neral (32.86), geranyl acetate (3.98), β-caryophyllene (1.59), linalool
(1.23), camphene (1.19), caryophyllene oxide (0.67), eugenol (0.48), limonene (0.23),
α-pinene (0.20), trans-β-ocimene (0.12)
Marjoram (Origanum
841 1.8 Cineole (48.05), linalool (22.69), limonene (8.10), α-pinene (4.42), β-pinene
(4.05), isobornyl acetate (2.82), para-cymene (2.21),,estragol (1.02), γ-terpinene
(0.96), camphene (0.74), wiridiorol (0.73), myrcene (0.51), borneol (0.49) trans-
linalool oxide (0.24), cis-linalool oxide (0.21)
Nutmeg (Myristica
889 α-Pinene (18.35), myristicin (17.65), β-pinene (12.29), sabinene (10.15), terpinen-4-ol
(8.21), γ-terpinene (4.18), limonene (3.63), para-cymene (3.15), α-terpinolene (2.91),
safrole (2.68), 1.8 cineole (2.16), terpinolene (1.84), methyl eugenol (1.59), α-terpineol
(1.52), δ-3-carene (1.41), elemicin (0.74), eugenol (0.53)
Orange (Citrus aurantium
820 Limonene (96.25), myrcene (1.81), linalool (0.49), α-pinene (0.49), sabinene (0.32),
β-phellandrene (0.27)
Palmarosa (Cymbopogon
874 Geraniol (57.49), geranyl acetate (13.56), linalool (1.71), beta-caryophyllene (1.07),
ocimene (0.27)
Patchouli (Pogostemon
1009 Patchoulol (25.21), δ-guaieno (11.49); gurjunene-α(11.26); seicheleno (9.61),
α-guaieno (9:56), benzyl alcohol (6.73), vidreno (3.12), aromadendrene (2.81),
α-cedrol (2.63), β-patchouleno (1.57)
(Continued )
Journal of Essential Oil Research 35
Downloaded by [UNESP] at 03:36 03 December 2013
performed by the dilution of EOs onto Mueller Hinton
agar (MHA) and the minimal inhibitory concentration
(MIC) against each and the MIC
and MIC
values were recorded.
Essential oils
Twenty-seven samples of EOs, from the supplier By
Samia Aromatherapy (São Paulo-SP, Brazil) in amber
glass vials with a capacity of 10 mL, were selected
according to their frequent use in aromatherapy proce-
dures. These EOs were: bergamot (Citrus aurantium
bergamia), black pepper (Piper nigrum), Brazils
spearmint (Mentha arvensis), cardamom (Elettaria
cardamomum), cedar (Cedrus atlantica), cinnamon
(Cinnamomum cassia), clary sage (Salvia sclarea), clove
(Syzygium aromaticum), copaiba (Copaifera ofcinalis),
cypress (Cupressus sempervirens), eucalyptus (Eucalyp-
tus globulus), fennel (Foeniculum vulgare), geranium
(Pelargonium graveolens), ginger (Zingiber ofcinalis),
lavender (Lavandula ofcinalis), lemongrass (Cymbopo-
gon schoenanthus), marjoram (Origanum majorana),
nutmeg (Myristica fragans), orange (Citrus aurantium
dulcis), palmarosa (Cymbopogon martinii), patchouli
(Pogostemon patchouli), pine (Pinus sylvestris), rose-
mary (Rosmarinus ofcinallis), Tahiti lime (Citrus limo-
num), tea tree (Melaleuca alternifolia), vetiver (Vetiveria
zizanioides) and ylang ylang (Cananga odorata). The
samples were kept at room temperature and the chemical
characterization of the oils samples were provided by
supplier, including the gas chromatographymass spec-
trometry (GCMS) analysis (Table 1). Density values
from each studied oil were performed using methodology
recommended by Fonseca and Librandi (15)in
Eppendorf tubes, which were weighed (P1) on an
analytical balance and then weighed again (P2) after the
addition of 1 mL (V) of oil. The density (D) was
calculated using the formula below.
Bacterial strains
The bacterial strains from the American Type Culture
Collection (ATCC) standard strains (E.coli ATCC
25922, S.aureus ATCC 25923 and P.aeruginosa
ATCC 27853), as well as ten S.aureus, ten E.coli and
nine P.aeruginosa isolated from human clinical speci-
mens, were selected from strains stored at 80°C in the
Department of Microbiology and Immunology of Bio-
sciences Institute of UNESP, Botucatu-SP. Prior to use,
the strains were plated on blood agar medium to check
viability and purity, and maintained on nutrient agar for
use in bacterial susceptibility assays.
Antimicrobial activity of EOs by the agar dilution
method and MIC
Susceptibility tests for determining the MIC of EOs were
carried out following the agar dilution method, adapted
from CLSI (16) protocol, the plate discs were prepared
and antimicrobial assays were performed during one day.
Each EO was diluted alone in MHA plus 0.5% Tween
80 at 45°C in Petri dishes and equivalent concentrations
of 0.025, 0.05, 0.1, 0.2, 0.5, 0.8, 1.0, 1.5, 2.0, 2.5 and
3.0% v/v were established. The strains were grown at
35°C/1824 hours in brain heart infusion (BHI) and
standard suspensions were performed in sterile saline
(0.85%) using scale 0.5 of MacFarland aiming a
Table 1. (Continued ).
Essential oil
(mg/mL) Compounds in essential oils (%)
Pine (Pinus sylvestris) 874 Bornyl acetate (32.74), camphene (21.67), α-pinene (10.95), limonene (4.42), 1.8
cineole (3.15), borneol (3.11), β-pinene (1.82), β-caryophyllene (1.53), terpinolene
(1.01), myrcene (0.54), geranyl acetate (12:34), camphor (0.22), para-cymene (0.14),
γ-terpinene (0.12)
Rosemary (Rosmarinus
885 1.8 Cineole (31.57), camphor (20:42), α-pinene (15.78), camphene (4.93), limonene
(3.76), geraniol (2.43), myrcene (2.02), linalool (1.70), para-cymene (1.66), γ-terpinene
(1.14), α-terpinolene (0.99), bornyl acetate (0.41), borneol (0.15)
Tahiti lime (Citrus
840 Limonene (62.34), γ-terpinene (11.96), β-pinene (10.23), β-bisabolene (2.68), α-pinene
(1.97), geraniol (1.84), myrcene (1.49), para-cymene (1.18), neral (1.04), trans-α-
bergamotene (1.02), α-tujeno (0.50)
Tea tree (Melaleuca
858 1-Terpinen-4-ol (53.40), p-cymene (8.9), gamma-terpinene (5.34), 1.8 cineole (3.18),
alpha-pinene (1.40), terpinolene (1.05), limonene (0.70)
Vetiver (Vetiveria
977 n/d
Ylang ylang (Cananga
904 trans-β-Caryophyllene (12.92), linalool (11.38), germacrene-d (11.21), benzyl acetate
(10.34), geranyl acetate (9.87).
Note: n/d, information not obtained.
36 B.F.M.T. Andrade et al.
Downloaded by [UNESP] at 03:36 03 December 2013
bacterial concentration about 1.5 × 10
colony forming
units (CFU)/mL. The inoculation of thirty-two strains,
from standardized suspensions, was made using a Sterr
multi-inoculator using suspensions standardized at 0.5
MacFarland, with a second dilution performed onto BHI
to obtain inoculum of an approximate concentration of
CFU/mL. After Petri dishes were inoculated
and incubated at 35°C/1824 hours, bacterial growth
was assessed and the MIC values were recorded for each
strain. The conversion of values from % v/v to mg/mL,
using the density values of each oil, and their
calculations of the MIC
and MIC
for each tested
bacterial strains were performed.
Statistical analysis
The results obtained were used to compare three
or more independent testing treatments via the
KruskalWallis test. For meaningful analysis (p0.001),
we apply the StudentNewmanKeuls test for multiple
comparisons tests between treatments.
Results and discussion
The research about antimicrobial activity, the action
mechanism and potential use of volatile plant oils has
received prominence in recent decades in parallel with
advances in traditional approaches to protecting the
health of humans, animals and food against the
presence of pathogenic and spoilage microorganisms.
Thus, investigations on the antimicrobial activity of
plant extracts against different pathogens have been
performed worldwide (17); our results have importance
because they provide information about this subject.
The density (mg/mL), chemical compounds and
their percentages in the total composition of the each
EO (twenty-seven samples) were found; results are
presented in Table 1. We emphasize that the data about
chemical analysis of the oils studied were received
from the company By Samia Aromatherapy who
supplied the EO samples. All of the oils studied
showed a density above 800 mg/mL, with orange oil
having the lowest value (820 mg/mL) and patchouli
(1009 mg/mL), cinnamon (1008 mg/mL) and clove
(988mg/mL) presenting the highest density values.
Although the chemical characterization of the oils plays
a role in studies of this nature, according to some
authors, it cannot be concluded that the major compo-
nent is the biologically active compound of this study,
so the effect can be attributed to a constituent or lesser
extent a synergy between existing compounds in the oil
(1821). In general, the EO showed diversity in their
chemical characterization, but these are in agreement
with the literature in question.
A total of twenty-seven oils were assayed by the
agar dilution method. The MIC
values against bac-
terial strain tested (Table 2) show that S.aureus strains
were susceptible to a high number of EOs, and eight of
the twenty-seven oils tested showed inhibitory activity
with MIC
values below 0.30 mg/mL (e.g. eucalyp-
tus, lemongrass, patchouli, black pepper, clary sage, tea
tree, vetiver, ylang ylang).
With the tests using the agar dilution methodology
at the concentrations tested, it was not possible to
achieve MIC values for P.aeruginosa strains, except
for cinnamon; these results corroborate those reported
by Hammer et al. (21), who determined the MIC
against E.coli and S.aureus but failed to nd results
for P.aeruginosa strains.
Thus, the S.aureus strains showed high susceptibil-
ity to natural products, which again conrms the results
from the literature (22,23), or in other words, Gram-
positive species are more sensitive to natural products
that Gram-negative bacteria.
These data are important for the treatment of infec-
tions caused by these bacteria; S.aureus is described as
one of the main agents responsible for infection, as its
virulence and ability to acquire antimicrobial resistance
results in a serious problem throughout the world for
hospitals and health professionals (24).
Pseudomonas aeruginosa is a Gram-negative bacte-
rium that produces water-soluble pigments, which is
widely distributed in soil and water, and is a hospital
pathogen that grows in damp areas such as sinks, bath-
tubs and showers; it is also considered a resistant bacte-
rium (25). Despite the fact that E.coli is a Gram-
negative bacteria as well as P.aeruginosa, this bacte-
rium showed sensitivity to fourteen oils at the highest
concentrations tested. These results corroborate with
those reported by Duarte et al. (26), who concluded
that the C.martini (palmarosa) EO and its major com-
ponent, geraniol, may be useful for the treatment of
diarrhoea caused by E.coli.
EOs mainly include two biosynthetic groups, all
characterized by low molecular weight, including aro-
matic and aliphatic constituents, and terpenes and terpe-
noids (27).
As a typical lipophilic compound, EOs cross the cell
wall and cytoplasmic membrane and the cytotoxic
activity appears to be linked to disruption of the struc-
tures of the different layers of polysaccharides, fatty
acids and phospholipids, due to its mechanism of action
that hits multiple targets at the same time (22). Perme-
ability, composition and charge of the outer structures of
the microorganisms mainly determined these differences;
the lipophilic character of terpenes is associated with the
antimicrobial mechanism (28). Numerous reports have
been made about the mechanisms of antimicrobial action
of the oils, and some cases have been partly elucidated,
Journal of Essential Oil Research 37
Downloaded by [UNESP] at 03:36 03 December 2013
e.g. the tea tree EO (M.alternifolia) and its major
compound, terpinen-4-ol, which causes lysis and loss of
membrane integrity due to output ions and cellular
respiration inhibition (29,30).
Cypress (C.sempervirens) was the only species that
showed no antibacterial activity according the suscepti-
bility assay performed. According to Hammer et al.
(21), this oil also showed no activity against E.coli
and P.aeruginosa, although it has some effect on the
growth of strains of S.aureus with an MIC value of
2% v/v. However, the authors report that a single stan-
dard NCTC strain (National Collection of Type Cul-
tures) was used, which may explain the different results
obtained, while this study tested strains isolated from
human clinical cases, and therefore distinct phenotypes
itself. However, C.arizonica, from the same family as
C.sempervirens, has been attributed weak antimicrobial
activity for this EO because of the high hydrocarbon
content (31).
EO contain complex mixtures of components and
thus have multiple antimicrobial properties; most of this
action appears to derive from oxygenated terpenoids,
particularly phenolic terpenes, phenylpropanoids and
alcohols; other constituents, e.g. hydrocarbons that
typically showed low activities, can be used in
combinations to increase their bioactivities (27).
In general, the oils of cinnamon and clove oils were
those with the highest potential inhibitors against the
three bacterial strains used. According to Prabuseeniva-
san et al. (32), these oils were able to inhibit the
growth of both Gram-positive and Gram-negative
species. Both oils showed eugenol, i.e. phenylpropa-
noid, to be the main compound.
The clove EO exhibited the best activity among the
twenty-seven oils tested against both Gram-negative
strains, but for the strains of S.aureus, this was black
pepper oil with an MIC
of 0.21 mg/mL.
Most of the EOs used in this study has terpinen-
4-ol, linalool and eugenol as part of their compounds.
The antimicrobial mechanism involved with linalool
is related to its high water solubility and to its ability
to penetrate the bacteria cell wall (33). One hypothesis
is that linalool has the potential to act as either a pro-
tein denaturing agent or as a solvent dehydrating agent,
Table 2. Minimal inhibitory concentration 50% (MIC
) and 90% (MIC
) (mg/mL) found on essential oils samples against
ATCC standard and Staphylococcus aureus,Escherichia coli and Pseudomonas aeruginosa strains isolated from clinical human
Essential oil
S.aureus (n=11)*,
E.coli (n=11)*,
P.aeruginosa (n=10)**,
Bergamot (Citrus aurantium bergamia) 10.5019.81
>26.13>26.13 >26.13>26.13
Black pepper (Piper nigrum) 0.210.21
>25.38>25.38 >25.38>25.38
Brazils spearmint (Mentha arvensis) 1.902.26
5.52 -5.52 >25.47>25.47
Cardamom (Elettaria cardamomum) 7.587.58
>26.07>26.07 >26.07- >26.07
Cedar (Cedrus atlantica) 1.782.76
Cinnamon (Cinnamomum cassia) 1.001.14
25.00 30.0
Clary sage (Salvia sclarea) 0.290.29
>25.71>25.71 >25.71>25.71
Clove (Syzygium aromaticum) 0.67 -1.21
Copaiba (Copaifera ofcinalis) 24.0726.52
>26.52>26.52 >26.52>26.52
Cypress (Cupressus sempervirens) >25.2>25.2 >25.20>25.20 >25.20>25.20
Eucalyptus (Eucalyptus globulus) 0.220.22
Fennel (Foeniculum vulgare) 7.817.81
Geranium (Pelargonium graveolens) 0.20- 0.31
Ginger (Zingiber ofcinalis) 3.234.93
>25.5>25.5 >25.50>25.50
Lavender (Lavandula ofcinalis ofcinalis) 2.374.27
Lemongrass (Cymbopogon schoenanthus) 0.150.22
Marjoram (Origanum majorana) 4.214.21
>25.23 ->25.23
Nutmeg (Myristica fragans) 13.9613.96
>26.67- >26.67
Orange (Citrus aurantium dulcis) 12.5016.5
>24.63>24.63 >24.63>24.63
Palmarosa (Cymbopogon martinii) 0.480.59
>26.22- >26.22
Patchouli (Pogostemon patchouli) 0.250.25
>30.27>30.27 >30.27>30.27
Pine (Pinus sylvestris) 2.582.58
>26.22>26.22 >26.22>26.22
Rosemary (Rosmarinus ofcinallis) 6.407.26
Tahiti lime (Citrus limonum) 10.014.91
>25.2>25.2 >25.2>25.2
Tea tree (Melaleuca alternifolia) 0.210.21
Vetiver (Vetiveria zizanioides) 0.240.24
>29.31>29.31 >29.31>29.31
Ylang ylang (Cananga odorata) 0.230.23
>27.12>27.12 >27.12>27.12
Note:*ATCC and plus ten clinical isolated; **ATCC and plus nine clinical isolated. Values preceded by >were not considered in the statistical
analysis because they did not show inhibitory capacity up to the maximum concentration tested in the trials. Different letters in columns represent
statistical differences for antibacterial activities of essential oils (mg/mL) when p0.001.
38 B.F.M.T. Andrade et al.
Downloaded by [UNESP] at 03:36 03 December 2013
which may also contribute to its antimicrobial activity
The antimicrobial activity of some EOs could be
explained by the signicant amount of linalool, which
is an oxygenated monoterpenoid (35). Knobloch et al.
(36) related that linalool had a signicantly increased
antimicrobial activity when compared to eugenol. Over-
all, the antibacterial activity of the EOs can be related
to the content of many of the compounds identied in
the oils, including eugenol (17,37).
Although linalool presents important antioxidant
and antimicrobial effects (38), it must be noted that the
antimicrobial effect of an EO depends on all of its
chemical components (35).
Thus, we concluded that P.aeruginosa strains were
highly resistant to the EOs, while the S.aureus strains
were considerably sensitive, although the potential use
of EOs can be applied to both Gram-positive and
Gram-negative bacteria.
The authors are grateful to the company By Samia Aroma-
therapy for providing the samples of essential oils as well as
by chemical analysis of the samples. Also thank Prof. Dr. Lu-
ciano Barbosa of Department of Biostatistics/Biosciences
Institute, UNESP, by statistics analysis of the results from the
Conict of interest
The authors have declared no conict of interest
(1) C.M. Franz, Essential oil research: Past, present and
future. Flavour Fragr. J., 25,112113 (2010).
(2) F. Bakkali, S. Averbeck, D. Averbeck and M. Idaomar,
Biological effects of essential oils A review. Food
Chem. Toxicol., 46, 446475 (2008).
(3) L. Gobbo-Neto and N.P. Lopes, Plantas medicinais: Fat-
ores de inuência no conteúdo de metabólitos secundár-
ios. Quim. Nova, 2, 374381 (2008).
(4) M. Mazutti, B. Beledelli, A.J. Mossi, R.L. Cansian,
C. Dariva, J.V. Oliveira and N. Paroul, Caracterização
química de extratos de Ocimum basilicum L. obtidos
através de extração com CO
a altas pressões. Quim.
Nova, 6, 11981202 (2006).
(5) S. Rajkumar and A. Jebanesan, Chemical composition
and larvicidal activity of leaf essential oil from Clausena
dentata (Willd) M. Roam. (Rutaceae) against the chi-
kungunya vector, Aedes aegypti Linn. (Diptera: Culici-
dae). J. Asia Pac. Entomol., 13, 107109 (2010).
(6) W.A. Wannes, B. Mhamdi, J. Sriti, M.B. Jemia, O. Ouc-
hikh, G. Hamdaoui, M.E. Kchouk and B. Marzou, Anti-
oxidant activities of the essential oils and methanol
extracts from myrtle (Myrtus communis var. italica L.)
leaf, stem and ower. Food Chem. Toxicol., 48,
13621370 (2010).
(7) S.S. Mendes, R.R. Bomm, H.C.R. Jesus, P.B. Alves,
A.F. Blank, C.S. Estevam, A.R. Antoniolli and S.M.
Thomazzi, Evaluation of the analgesic and anti-inam-
matory effects of the essential oil of Lippia gracilis
leaves. J. Ethnopharmacol., 129, 391397 (2010).
(8) E.S. Carmo, E.O. Lima and E.L. Souza, The potential of
Origanum vulgare L. (Lamiaceae) essential oil in inhibit-
ing the growth of some food-related Aspergillus species.
Braz. J. Microbiol, 39, 362367 (2008).
(9) S.L. Silva, J.S. Chaar, P.M.S. Figueiredo and T. Yano,
Cytotoxic evaluation of essential oil from Casearia syl-
vestris Sw on human cancer cells and erythrocytes. Acta
Amazonica, 1, 107112 (2008).
(10) P. López, C. Sánchez, R. Batlle and C. Nerín, Solid-
and vapor-phase antimicrobial activities of six essential
oils: Susceptibility of selected foodborne bacterial and
fungal strains. J. Agric. Food Chem., 53, 69396946
(11) R.S. Pereira, T.C. Sumita, M.R. Furlan, A.O.C. Jorge
and M. Ueno, Atividade antibacteriana de óleos essenci-
ais em cepas isoladas de infecção urinária. Rev. Saude
Publica, 2, 326328 (2004).
(12) S. Hemaiswarya, A.K. Kruthiventi and M. Doble, Syner-
gism between natural products and antibiotics against
infectious diseases. Phytomedicine, 15, 639652 (2008).
(13) M.A. Fischbach and C.T. Walsh, Antibiotics for emerg-
ing pathogens. Science, 5944, 10891093 (2009).
(14) O.O. Okoh, A.P. Sadimenko and A.J. Afolayan, Com-
parative evaluation of the antibacterial activities of the
essential oils of Rosmarinus ofcinalis L. obtained by
hydrodistillation and solvent free microwave extraction
methods. Food Chem., 120, 308312 (2010).
(15) P. Fonseca and A.P.L. Librand, Evaluation of physico-
chemical and phytochemical characteristics of different
tinctures of barbatimão (Stryphnodendron barbatiman).
Braz. J. Pharm. Sci., 4, 271277 (2008).
(16) Clinical and Laboratory Standards Institute/National
Comitee for clinical Laboratory Standards (CLSI/
NCCLS). In: Performance Standards for Antimicrobial
Susceptibility Testing; Fifteenth Information Supplement.
CLSI/NCCLS document M 100S15. Wayne, PA,
(17) H.J.D. Dorman and S.G. Deans, Antimicrobial agents
from plants: Antibacterial activity of plant volatile oils.
J. Appl. Microbiol., 88, 308316 (2000).
(18) M.M. Cowan, Plant products as antimicrobial agents.
Clin. Microbiol. Rev, 12, 564582 (1999).
(19) P.J. Houghton, M.J. Howes, C.C. Lee and G. Steventon,
Uses and abuses of in vitro tests in ethnopharmacology:
Visualizing an elephant. J. Ethnopharmacol., 110,
391400 (2007).
(20) M.T. Pupo, M.B.C. Gallo and P.C. Vieira, Biologia
química: Uma estratégia moderna para a pesquisa
em produtos naturais. Quim. Nova, 6, 14461455
(21) K.A. Hammer, C.F. Carson and T.V. Riley, Antimicro-
bial activity of essential oils and other plant extracts.
J. Appl. Microbiol., 6, 985990 (1999).
(22) J.E.C. Betoni, R.P. Mantovani, L.N. Barbosa, L.C. Di
Stasi and A. Fernandes Júnior, Synergism between plant
extract and antimicrobial drugs used on Staphylococcus
aureus diseases. Mem. Inst. Oswaldo Cruz, 4, 387390
(23) N.C.C. Silva and A. Fernandes Junior, Biological
properties of medicinal plants: A review of their
Journal of Essential Oil Research 39
Downloaded by [UNESP] at 03:36 03 December 2013
antimicrobial activity. J. Venom. Anim. Toxins Incl.
Trop. Dis., 3, 402413 (2010).
(24) M.J. Carvalho, F.C. Pimenta, M. Hayashida, E. Gir,
A.M. Silva, C.P. Barbosa, S.R.M.S. Canini and S.
Santiago, Prevalence of methicillin-resistant and
methicillin-susceptible S. aureus in the saliva of health
professionals. Clinics, 4, 295302 (2009).
(25) E. Jawetz, J. Melnick and E. Aldelberg, Microbio-
logia médica: Um livro médico Lange., McGraw-
Hill Interamericana do Brasil, Rio de Janeiro
(26) M.C.T. Duarte, E.E. Leme, C. Delarmelina, A.A. Soares,
G.M. Figueira and A. Sartoratto, Activity of essential oils
from Brazilian medicinal plants on Escherichia coli.
J. Ethnopharmacol., 111, 197201 (2007).
(27) I. Bassole and H. Juliani, Essential oils in combination
and their antimicrobial properties. Molecules, 17,
39894006 (2012).
(28) P. Roman, KS. Martyna, T. Mariusz and F. Jan,
Terpenes: Substances useful in human healthcare. Arch.
Immunol. Ther. Exp., 55, 315327 (2007).
(29) S.D. Cox, J.L. Mann, H.C. Bell, J.E. Gustafson,
J.R. Warmingtn and S.G. Wyllic, The mode of
antimicrobial action of the essential oils of Melaleuca
alternifolia (tea tree oil). J. Appl. Microbiol, 88,
170175 (2000).
(30) C.F. Carson, K.A. Hammer and T.V. Riley, Melaleuca
alternifolia (tea tree) oil: A review of antimicrobial and
on the medicinal properties. Clin. Microbiol. Rev., 1,
5062 (2006).
(31) I. Cheraif, H. Ben Jannet, M. Hammami, M. Khouja
and Z. Mighri, Chemical composition and antimicrobial
activity of essential oils of Cupressus arizonica Greene.
Biochem Systematics Ecol., 35, 813820 (2007).
(32) S. Prabuseenivasan, M. Jayakumar and S. Ignacimthu,
In vitro antibacterial activity of some plant essential
oils. BMC Complement. Altern. Med., 39,18 (2006).
(33) P. Suppakul, J. Miltz, K. Sonneveld and S.W. Bigger,
Antimicrobial properties of basil and its possible appli-
cation in food packaging. J. Agric. Food. Chem., 51,
31973207 (2003).
(34) M.J. Pelczar, E.C.S. Chan and N.R. Krieg, Control of
Microorganism: Chemical Agents in Microbiology: Con-
cepts and Applications. McGraw-Hill, New York (1993).
(35) M. Stefan, M. Zamrache, C. Padurariu, E. Truta and
I. Gostin, The composition and antibacterial activity of
essential oils in three Ocimum species growing in
Romania. Cent. Eur. J. Biol., 8, 600608 (2013).
(36) K. Knobloch, A. Pauli, B. Iberl, H. Weigand and
N. Weis, Antibacterial and antifungal properties of
essential oil components. J. Essent. Oil Res., 1989 (1),
118119 (1989).
(37) B. Ouattara, R.E. Simard, R.A. Holley, G.J.P. Piette and
A. Bégin, Antibacterial activity of selected fatty acids
and essential oils against six meat spoilage organisms.
Int. J. Food Microbiol., 37, 155162 (1997).
(38) C.L. Queiroga, M.C. Teixeira Duarte, B. Baesa Ribeiro
and P.M. de Magalhães, Linalool production from the
leaves of Bursera aloexylon and its antimicrobial
activity. Fitoterapia, 78, 327328 (2007).
40 B.F.M.T. Andrade et al.
Downloaded by [UNESP] at 03:36 03 December 2013
... The antimicrobial activity of essential oils has been one of the most extensively researched topics in recent decades, particularly in developed countries (Murbach Teles Andrade et al. 2014;Reyes-Jurado et al. 2015;Chouhan et al. 2017;Sharma et al. 2020;Galgano et al. 2022). The availability, effectiveness, and safety of these antimicrobial agents are the primary concerns of this trend. ...
Full-text available
Biofilms are the primary source of contamination linked to nosocomial infections by promoting bacterial resistance to antimicrobial agents, including disinfectants. Using essential oils, this study aims to inhibit and eradicate the biofilm of enterobacteria and staphylococci responsible for nosocomial infections at Guelma Hospital, northeastern Algeria. Thymbra capitata, Thymus pallescens and Artemesia herba-alba essential oils were evaluated against clinical strains of Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus. The antimicrobial activity of the essential oils under consideration was assessed using an agar disc diffusion assay and the determination of minimum inhibitory concentrations (MICs). In addition, the crystal violet method and scanning electron microscopy (SEM) evaluated biofilm inhibition and eradication by those antimicrobial agents. The results indicate that T. pallescens essential oil was the most effective antimicrobial agent against pathogenic bacteria, with large zones of inhibition (up to 50 mm against S. aureus), low MICs (0.16 to 0.63 mg/mL), and powerful biofilm eradication up to 0.16 mg/mL in both 24 h and 60-min exposure times. Thus, Algerian thyme and oregano could be used in various ways to combat the biofilm that causes nosocomial infection in local hospitals.
... Plant EOs are natural extracts that have well-known antibacterial properties and are highly prized by customers as natural additives. Strong in vitro antibacterial activity of EOs and EO compounds, which has been widely explored and documented in the literature [19], is effective against a wide variety of spoilage microorganisms and pathogens. Additionally, EO treatments have been used to preserve quality aspects like colour, firmness, and others in fruit and vegetables after harvest [20,21]. ...
Full-text available
Plant essential oils (EOs) have an important ability to inhibit ethylene biosynthesis. Nevertheless, the effects of EOs on the key components of ethylene biosynthesis (l-aminocyclopropane-1-carboxylic (ACC) oxidase activity, ACC synthase activity, and ACC content) have not yet been thoroughly studied. Accordingly, this study focused on the effects of emitted EOs from active packaging (EO doses from 100 to 1000 mg m−2) on the key components of ethylene biosynthesis of blueberries and blackberries under several storage temperatures. Anise EO and lemon EO active packaging induced the greatest inhibitory effects (60–76%) on the ethylene production of blueberries and blackberries, respectively, even at high storage temperatures (22 °C). In terms of EO doses, active packaging with 1000 mg m−2 of anise EO or lemon EO led to the highest reduction of ethylene production, respectively. At 22 °C, the investigated EO active packing reduced the activities of ACC synthase and ACC oxidase up to 50%. In order to minimise ethylene biosynthesis in blueberries and blackberries when they are stored even under improper temperature scenarios at high temperatures, this EO active packaging is a natural and efficient technological solution.
... Still, after the industrial revolution, these materials were industrially developed, and in parallel, they began to be replaced by biocides processed in the laboratory, being mostly very harmful to the human organism (Martín-Rey et al., 2023). Previous studies reported the chemical composition of the five tested EOs according to the Gas Chromatography-Mass Spectroscopy GC-MS (Shi et al., 2013;Menon & Padmakumari, 2005;Murbach Teles Andrade et al., 2014;Wesołowska et al., 2015). ...
Full-text available
Based on the results of our previous work, the essential oils (EOs) of black pepper, red pepper, cinnamon, ginger, and camphor proved the top maximum efficiency among the fifty tested EOs against the eighteen tested fungi. The present study aims to assay the antifungal activities and the positive/negative effects of these five EOs against A. niger, A. flavus, C. halotolerans, and N. goegapense, as well as the prevalent deteriorating fungi isolated from the historical oil paintings and textiles in the Agricultural Museum in Dokki, Giza. The vapor technique was used to disinfect the fungi-contaminated mock-ups of oil painting, cotton, and wool fabrics using the plate method. Count of spores, macro and microscopic stereo and SEM techniques, FTIR spectros-copy, and colorimetric measurements were used in assessment. The results revealed the efficient antifungal activities of all tested EOs against the selected fungi, varying from the highest (99.85%) for black pepper EO against N. goegapense to the lowest (71.65%) for camphor EO against N. goegapense. It proved that the EO of black pepper was the most potent and efficient EO among the tested ones against A. flavus, C. halotolerans, and N. goegapense. Regarding A. niger, the study revealed that the EO of ginger proved the most potent and efficient EO against it. The vapor phase method proved a very efficient and non-destructive technique against the infected mock-ups. In some cases, it eradicated up to ~100% of fungi without any notable changes in the properties of the treated mock-ups. A small amount of black pepper EO was advised to be vapored in all closed display and storage cases in the museums as a preventive technique to inhibit the fungal growth of heritage materials.
... RIcal: Retention index determined relative to n-alkanes (C7-C30) on the HP-5ms column. RI: literature retention indices climatic conditions can also affect yield and chemical composition [23]. ...
Full-text available
Plants are the richest sources of bioactive compounds and have been the basis of orthodox medicines since ancient times and has continued to provide cure to diseases of mankind. This study investigated the chemical composition, antimicrobial and antioxidant activities of essential oil extracted from the dried flower bud of Eugenia aromatica L. The clove buds essential oil obtained through hydro distillation using the Clevenger apparatus was then analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Later on the antimicrobial assay was carried out using the agar duffusion method. In vitro antioxidant was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, ferric reducing antioxidant power, nitric oxide radical scavenging, total antioxidant capacity and lipid peroxidation assays on the extracted essential oil. The major components of the extracted essential oil of Eugenia aromatica L. are Eugenol (76.13%) and Eugenol acetate (19.01%). Results of the antioxidant activities of the essential oil showed promising antioxidant potentials when compared to the positive control (ascorbic acid), strong nitric oxide scavenging activity was observed in the essential oil (IC50 of 24.78 µg/mL) than that of the standard drug used (IC50 of 34.24 µg/mL). The antimicrobial activities of the essential oil against the most frequently encountered microorganisms which include Staphylococcus aureus (ATCC 29213), Streptococcus mutans, Escherichia coli (ATCC 25922) and Candida albicans (ATCC 10231) showed significant broad spectrum antibacterial and antifungal activities with zones of inhibition (mm) against Staphylococcus aureus (20.00± 0.0), Streptococcus mutans (32.00± 1.4), Escherichia coli (30.00 ± 0.0) and Candida albicans (28 ± 5.7).
... RIcal: Retention index determined relative to n-alkanes (C7-C30) on the HP-5ms column. RI: literature retention indices climatic conditions can also affect yield and chemical composition [23]. ...
Full-text available
O Cymbopogon martinii (Palmarosa) é pertence à família das Poaceae. Plantas pertencentes a este gênero são perenes, raramente anuais. Possuem colmos eretos, que podem medir de 30 cm até 3 metros de altura. O óleo essencial de Palmarosa tem ação antibacteriana e antifúngica atribuída principalmente ao geraniol. Exibe atividade antioxidante, inibindo os radicais livres e espécies reativas de oxigênio, os quais têm o potencial de ocasionar danos celulares, como a interferência na síntese de DNA. Devido o surgimento de novos microrganismos que demonstram resistência ao tratamento com medicamentos já existentes, é de considerável importância a investigação das propriedades bioativas do óleo essencial de Cymbopogon martinii com ênfase na atividade antimicrobiana. Foi avaliado a atividade antibacteriana e antifúngica do óleo essencial de Cymbopogon martinii (Palmarosa), frente as cepas ATCC: Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 e Klebsiella pneumoniae ATCC 700603 e as cepas fúngicas ATCC: Candida albicans ATCC 76615, Candida guilliermondii ATCC 6260, Candida glabrata ATCC 90030. A ação antimicrobiana de Cymbopogon martinii foi avaliada qualitativamente usando o método de difusão em Agar modificado, uma técnica descrita por Brcast 2023, bem como quantitativamente por meio da macrodiluição em caldo. Na técnica de disco difusão, o óleo essencial de Cymbopogon martinii não se mostrou eficaz contra as bactérias gram-negativas e pouca atividade para as gram-positivas escolhidas. Entre as bactérias gram-positivas, a atividade de inibição foi observada contra Staphylococcus aureus, formando um halo de 15mm; no entanto, a bactéria gram-positiva, Enterococcus faecalis, não apresentou atividade inibitória. Entre as bactérias gram-negativas, nenhuma demonstrou atividade de inibição – isso inclui Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae. Já para a atividade antifúngica utilizando a Candida albicans, Candida guilliermondii e Candida glabrata, apresentaram halo de 25mm, 30mm e 15mm respectivamente. Já no teste de diluiçao em caldo não foi observada atividade de sensibilidade em nenhuma das diluições utilizadas do óleo essencial bruto de Palmarosa. Infere-se a partir desta pesquisa que o óleo essencial de Cymbopogon martinii apresentou melhor atividade de ação em difusão em Agar (qualitativo) contra a bactéria gram-positiva Staphylococcus aureus. Entre os gram-negativos, não se evidenciou resultado de sensibilidade em nenhuma, tanto na técnica qualitativa quanto na técnica quantitativa, das bactérias analisadas, isso inclui – Klebsiella pneumoniae, Pseudomonas aeruginosa e Escherichia coli. No que se refere á atividade antifúngica, o óleo essencial de Palmarosa apresentou excelente atividade contra as cepas Candida albicans, Candida guilliermondii e Candida glabrata.
Full-text available
Asparagus flagellaris essential oils of the leaves and roots comprised of twenty-eight (28) and nineteen (19) compounds in total, accounting 97.41 and 97.03% of the oil, respectively, were discovered using GC-MS analysis. According to reports, the EOs are a blend of terpenes, terpene derivatives, non-terpenes, thymol and its derivatives. Additionally, thymol derivatives predominated in the essential oils. When compared to the reference standards Tioconazole and Gentamicin for fungi (28 mm) and bacteria (40–35 mm), respectively, the essential oil exhibited a moderate inhibitory zone (18–10 mm) on the tested organisms. Thu, the essential oils were categorized as bacteriostatic. On the DPPH radical scavenger properties, interaction between the constituents identified in the essential oils demonstrated a distinctive a free radical scavenging activity. The chemical components of A. flagellaris’ essential oils play a key role in both its antioxidant and antibacterial properties.
Full-text available
Essential oils (EOs) extracted from plants have a high potential to reduce ethylene biosynthesis, although their effects have not been deeply studied yet on the key components of the ethylene biosynthesis pathway: l-aminocyclopropane-1-carboxylic (ACC) oxidase activity, ACC synthase activity, and ACC content. Hence, the present study aimed to elucidate the effects of released EOs from active packaging (with different EO doses ranging from 100 to 1000 mg m−2) on the ethylene biosynthesis key components of broccoli and tomato under different storage temperature scenarios. The largest ethylene inhibitory effects on broccoli and tomatoes were demonstrated by grapefruit EO and thyme essential EO (up to 63%), respectively, which were more pronounced at higher temperatures. Regarding EO doses, active packaging with a thyme EO dose of 1000 mg m−2 resulted in the strongest reduction (33–38%) of ethylene production in tomatoes. For broccoli, identical results were shown with a lower grapefruit EO dose of 500 mg m−2. The studied EO-active packaging decreased ACC synthase and ACC oxidase activities by 40–50% at 22 °C. Therefore, this EO-active packaging is a natural and effective technology to reduce ethylene biosynthesis in broccoli and tomatoes when they are stored, even in unsuitable scenarios at high temperatures.
Full-text available
Efficacies of essential oils (EOs) of Vetiveria zizanioides (L.) Nash. (Poales: Poaceae) (VZ EO), Cananga odorata (Lam) Hook. F. & Thomson (Magnoliales: Annonaceae) (CO EO), and crude extract (CE) of Andrographis paniculata (Burm.F.) Wall ex. Nees (Lamiales: Acanthaceae) (AP CE), against laboratory (lab) and field strains of Culex quinquefasciatus Say were investigated. Irritant and repellent activities of individual and binary mixtures of plant extracts were compared with N,N-diethyl-m-toluamide (DEET) using an excito-repellency system. The irritant activity (direct tarsal contact), the mean percent escape response of VZ EO (91.67%, 83.33%), and CO EO (80%, 88.33%) were not significantly different compared with DEET (88.33%, 95%) against lab and field strains, respectively. Similarly, irritant responses in combinations (1:1 and 1:2, v:v) of either VZ EO or CO EO with AP CE were not significantly different from DEET against both strains (P > 0.001). The repellent activity (no tarsal contact), the mean percent escape response of VZ EO (68.33%), CO EO (61.67%), and VZ EO+AP CE (1:1, v:v) (81.67%) against lab strain and CO EO (85%) against field strain were not significantly different from that of DEET (P > 0.001). Interestingly, the greatest contact irritancy of VZ EO+AP CE (1:1, v:v) (96.67%) (P = 0.0026) and a stronger repellency response of CO EO (85%) (P = 0.0055) produced significantly different patterns of escape response compared with DEET against both lab and field strains, respectively. The EOs of VZ EO and CO EO or their mixture with AP CE showed potential as plant-based active ingredients for mosquito repellents. In addition, the major chemical constituents of VZ EO were β-vetivone (6.4%), khusimol (2.96%), and α-vetivone (2.94%) by gas chromatograpy-mass spectrometry.
Full-text available
This work reports extraction yield and chemical characterization of the extracts obtained by high-pressure CO2 extraction of a cultivar of Ocimum basilicum L. The experiments were performed in the temperature range of 20 to 50 °C, from 100 to 250 atm of pressure. Chemical analyses were carried out by gas chromatography coupled to mass spectrometry, permitting to identify 23 compounds that were grouped into five chemical classes. Results showed that temperature and solvent density influenced positively the extraction yield. At 20 °C and 0.41 g cm-3 occurred a rise in the concentration of monoterpenes, oxygenated monoterpenes, sesquiterpenes and oxygenated sesquiterpenes.
Full-text available
This work reports extraction yield and chemical characterization of the extracts obtained by high-pressure CO2 extraction of a cultivar of Ocimum basilicum L. The experiments were performed in the temperature range of 20 to 50 °C, from 100 to 250 atm of pressure. Chemical analyses were carried out by gas chromatography coupled to mass spectrometry, permitting to identify 23 compounds that were grouped into five chemical classes. Results showed that temperature and solvent density influenced positively the extraction yield. At 20 °C and 0.41 g cm-3 occurred a rise in the concentration of monoterpenes, oxygenated monoterpenes, sesquiterpenes and oxygenated sesquiterpenes.
Full-text available
Plants have been used for thousands of years to flavor and conserve food, to treat health disorders and to prevent diseases including epidemics. The knowledge of their healing properties has been transmitted over the centuries within and among human communities. Active compounds produced during secondary vegetal metabolism are usually responsible for the biological properties of some plant species used throughout the globe for various purposes, including treatment of infectious diseases. Currently, data on the antimicrobial activity of numerous plants, so far considered empirical, have been scientifically confirmed, concomitantly with the increasing number of reports on pathogenic microorganisms resistant to antimicrobials. Products derived from plants may potentially control microbial growth in diverse situations and in the specific case of disease treatment, numerous studies have aimed to describe the chemical composition of these plant antimicrobials and the mechanisms involved in microbial growth inhibition, either separately or associated with conventional antimicrobials. Thus, in the present work, medicinal plants with emphasis on their antimicrobial properties are reviewed.
Full-text available
Origanum vulgare L. (Lamiaceae) has been currently known for their interesting antimicrobial activity being regarded as alternative antimicrobial for use is food conservation systems. This study aimed to evaluate the effectiveness of O. vulgare essential oil in inhibiting the growth of some food-related Aspergillus species (A. flavus, A. parasiticus, A. terreus, A. ochraceus, A. fumigatus and A. niger). The essential oil revealed a strong anti-Aspergillus property providing an inhibition of all assayed mould strains. MIC values were between 80 and 20 μL/mL being found a MIC50 of 40 μL/mL. The essential oil at concentration of 80 and 40 μL/mL provided a fungicidal effect on A. flavus, A. fumigatus and A. niger noted by a total inhibition of the radial mycelial growth along 14 days of interaction. In addition, the essential oil was able to inhibit the mould spores germination when assayed at concentrations of 80 and 40 μL/mL. Our results showed the interesting anti-Aspergillus activity of O. vulgare essential oil supporting their possible use as anti-mould compound in food conservation.
As a consequence of the large distribution and use of medicinal plants, the industries are producing products based on plant species in various pharmaceutical forms, which have been commercialized in pharmacies and natural products homes. However, there is no guarantee for the vast majority of these products, as to their effctiveness, safety, and quality, which may cause risks to the health of consumers. There it is important the establishment of standardized protocols of quality control for phytotherapeutic products. Tinctures of barbatimao are available in the Brazilian market proceeding from diverse manufacturers. With the purpose to evaluate the difference between the quality of tinctures of barbatimao proceeding from four manufactures, a comparative study of ph ysico-chenfical andphylocheinical characteristics was carried out. For physico-chemical analysis, the pH, density, dry residue and tannins content were evaluated. The phytochemical analysis was made using thin layer chromatography. The differences observed in physico-chemical and phytochemical characteristics had evidenced the lack of standardization in the production of these tinctures.
This paper presents an overview of the Natural Products Research in Brazil in the last five years (2002-2006), and also discusses how some relevant aspects of the Chemical Biology area could create new research opportunities and challenges for the natural product chemists. In addition, some aspects of the scientific policies and their impact on current projects are discussed.
The solubility in water of essential oil constituents is directly related to their ability to penetrate the cell walls of a bacterium or fungus. The antimicrobial activity of essential oils is due to their solubility in the phospholipid bilayer of cell membranes. Terpenoids which are characterized by their lability have been found to interfere with the enzymatic reactions of energy metabolism.