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Anti-fungal activities of Origanum oil against Candida albicans

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The antimicrobial properties of volatile aromatic oils from medicinal as well as other edible plants has been recognized since antiquity. Origanum oil, which is used as a food flavoring agent, possesses a broad spectrum of in vitro antimicrobial activities attributed to the high content of phenolic derivatives such as carvacrol and thymol. In the present study, antifungal properties of origanum oil were examined both in vitro and in vivo. Using Candida albicans in broth cultures and a micro dilution method, comparative efficacy of origanum oil, carvacrol, nystatin and amphotericin B were examined in vitro. Origanum oil at 0.25 mg/ml was found to completely inhibit the growth of C. albicans in culture. Growth inhibitions of 75% and >50% were observed at 0.125 mg/ml and 0.0625 mg/ml level, respectively. In addition, both the germination and the mycelial growth of C. albicans were found to be inhibited by origanum oil and carvacrol in a dose-dependent manner. Furthermore, the therapeutic efficacy of origanum oil was examined in an experimental murine systemic candidiasis model. Groups of mice (n = 6) infected with C. albicans (5 LD50) were fed varying amounts of origanum oil in a final vol. of 0.1 ml of olive oil (vehicle). The daily administration of 8.6 mg of origanum oil in 100 l of olive oil/kg body weight for 30 days resulted in 80% survivability, with no renal burden of C. albicans as opposed to the group of mice fed olive oil alone, who died within 10 days. Similar results were obtained with carvacrol. However, mice fed origanum oil exhibited cosmetically better clinical appearance compared to those cured with carvacrol. The results from our study encourage examination of the efficacy of origanum oil in other forms of systemic and superficial fungal infections and exploration of its broad spectrum effect against other pathogenic manifestations including malignancy.
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Molecular and Cellular Biochemistry 228: 111–117, 2001.
© 2001 Kluwer Academic Publishers. Printed in the Netherlands.
Antifungal activities of origanum oil against
Candida albicans
Vijaya Manohar,1 Cass Ingram,2 Judy Gray,2 Nadeem A. Talpur,1 Bobby
W. Echard,1 Debasis Bagchi3 and Harry G. Preuss1
1Department of Physiology and Biophysics, Georgetown University Medical Center, Washington, DC; 2North American
Herbs and Spices, Waukeegan, IL; 3Department of Pharmacy Sciences, Creighton University School of Pharmacy and AHP,
Omaha, NE, USA
Received 27 June 2001; accepted 14 September 2001
Abstract
The antimicrobial properties of volatile aromatic oils from medicinal as well as other edible plants has been recognized since
antiquity. Origanum oil, which is used as a food flavoring agent, possesses a broad spectrum of in vitro antimicrobial activities
attributed to the high content of phenolic derivatives such as carvacrol and thymol. In the present study, antifungal properties
of origanum oil were examined both in vitro and in vivo. Using Candida albicans in broth cultures and a micro dilution method,
comparative efficacy of origanum oil, carvacrol, nystatin and amphotericin B were examined in vitro. Origanum oil at 0.25
mg/ml was found to completely inhibit the growth of C. albicans in culture. Growth inhibitions of 75% and >50% were ob-
served at 0.125 mg/ml and 0.0625 mg/ml level, respectively. In addition, both the germination and the mycelial growth of C.
albicans were found to be inhibited by origanum oil and carvacrol in a dose-dependent manner. Furthermore, the therapeutic
efficacy of origanum oil was examined in an experimental murine systemic candidiasis model. Groups of mice (n = 6) infected
with C. albicans (5 × LD50) were fed varying amounts of origanum oil in a final vol. of 0.1 ml of olive oil (vehicle). The daily
administration of 8.6 mg of origanum oil in 100 µl of olive oil/kg body weight for 30 days resulted in 80% survivability, with
no renal burden of C. albicans as opposed to the group of mice fed olive oil alone, who died within 10 days. Similar results
were obtained with carvacrol. However, mice fed origanum oil exhibited cosmetically better clinical appearance compared to
those cured with carvacrol. The results from our study encourage examination of the efficacy of origanum oil in other forms
of systemic and superficial fungal infections and exploration of its broad spectrum effect against other pathogenic manifesta-
tions including malignancy. (Mol Cell Biochem 228: 111–117, 2001
Key words: antifungal activity, in vitro, in vivo, female BALB/c mice, origanum oil, Candida albicans, carvacrol, nystatin,
amphotericin B
Introduction
The antimicrobial properties of volatile aromatic oils from
edible plants have been recognized since antiquity. Origa-
num oil, which is used as a food flavoring agent, has been
shown to possess a broad spectrum of antimicrobial activ-
ity due to its high content of phenolic derivatives such as
carvacrol and thymol [1–3]. Earlier studies have demon-
strated the ability of origanum oil to retard and inhibit the
growth of various food spoiling organisms including the
species of Aspergillus (mycotoxinogenic filamentous fungi)
and Hansenula (industrial yeasts) [4–7]. While the oil and
many of its constituents have been demonstrated to be an-
tifungal in vitro against non-pathogenic yeasts [8, 9], a few
studies have suggested a potential therapeutic effect against
experimental infections in rats due to Trichophyton rubrum,
a human dermatophytic filamentous fungus) [10]. Never-
theless, very little information is available on its compara-
Address for offprints: H.G. Preuss, Department of Physiology and Biophysics, Georgetown University Medical Center, Med-Dent Building, SE103, 3900
Reservoir Road, NW, Washington, DC 20007, USA (E-mail: preusshg@georgetown.edu)
112
tive antifungal activity on the growth and physiology of
human pathogenic yeasts or filamentous fungi either in vitro
or in vivo. Furthermore, its direct therapeutic use either in
superficial or systemic infections due to bacteria or fungi has
not been clearly established. In the present study, we exam-
ined the antifungal properties of origanum oil and its major
chemical constituent carvacrol against Candida albicans, a di-
morphic yeast-like fungus. C. albicans which resides as com-
mensal in the mucocutaneous cavities of skin, vagina and
intestine of humans [11], can cause infections under altered
physiological and pathological conditions such as infancy,
pregnancy, diabetes, prolonged broad spectrum antibiotic ad-
ministration, steroidal chemotherapy as well as AIDS [12–
18]. We have demonstrated that origanum oil inhibits the
growth of C. albicans in vitro as well as in vivo. We conclude
that the daily oral administration of origanum oil may be highly
effective in the prevention and treatment of candidiasis.
Materials and methods
Animals and treatment
Female BALB/c mice (15–18 g) were obtained from Taconic
Farms (Germantown, NY, USA). The animals were main-
tained in a controlled environment at 25°C with a 12 h light
and 12 h dark cycle, and were acclimatized for 3–5 days
before use. The mice were housed in groups of five, fed com-
mercial rodent pellets and given water ad libitum through-
out the experiments. The protocol for the entire investigation
was approved by the Animal Welfare Board at Georgetown
University Medical Center.
Plant oils and chemicals
Origanum (P73 OreganolTM) and olive oil were provided by
North American Herbs and Spices, Waukegan, IL, USA. Car-
vacrol, nystatin and amphotericin B were purchased from
Sigma Chemical Co. (St. Louis, MO, USA). Sabouraud’s glu-
cose (S.g) broth and agar media were purchased from Difco
Laboratories (Detroit, MI, USA). All other chemicals used
in this study were obtained from Sigma Chemical Co. (St
Louis, MO, USA) and were of analytical grade or the high-
est commercial grade available.
Organisms
Standard strain of Candida albicans (ATCC No. 48274) ob-
tained from ATCC, Fairfax, VA, USA, was grown and main-
tained on S.g. agar slants.
Susceptibility testing
A micro-broth dilution technique was employed to determine
the susceptibility of the strains of C. albicans to oil of origa-
num and carvacrol [19, 20]. Susceptibility was expressed as
minimum inhibitory concentration (MIC) and minimum fun-
gicidal concentration (MFC). The stock solutions of origa-
num oil, olive oil and carvacrol (63% v/v adjusted in olive
oil) were dissolved in ethanol-Tween 80 solvent. Nystatin and
amphotericin B were dissolved in 50% ethanol, and used as
positive controls. Solvent and media controls were also in-
cluded for reference. The Sabouraud’s glucose (S.g) broth
containing varying amounts (logarithmic, serially and 2-fold
diluted) of origanum oil and carvacrol and the various con-
trols were inoculated with actively dividing C. albicans cells.
The cultures were incubated for 24 and 48 h at 30°C on a
metabolic rotary shaker (200 rev/min), and the growth was
monitored both visually and colorimetrically (at 540 nM).
The minimum inhibitory concentration (MIC) was defined
as the lowest concentration required to arrest the growth of
the fungi at the end of 24 h of incubation. Minimum fungi-
cidal concentration (MFC) was determined by sub-culturing
a 0.01 ml aliquot of the medium drawn from the culture tubes
showing no macroscopic growth at the end of 48 h of cul-
ture on S.g. agar plates and incubated further for the appear-
ance of yeast-like growth. The plates were scored for growth
of the yeast colonies. The lowest concentration of the anti-
fungal agent from which negative growth or fewer than 3
colonies were recorded was considered as minimum fungi-
cidal concentration (MFC).
Effect on yeast and mycelial forms of C. albicans
The effect of origanum oil on the formation of germ tubes
(filament initiation) by C. albicans was examined, by incu-
bating the blastospores with various concentrations of origa-
num oil, carvacrol and other agents in 20% egg albumin at
37°C [21]. The comparative percentage inhibition of germ
tube formation was determined by microscopic examination.
The effect on the mycelial formation (filament elongation) was
carried out by incubating the previously germinated blasto-
spores of C. albicans in the presence of varying amounts of
antifungal agents at 37°C for an additional 24 h and 48 h. Both
the germination and the filament elongation were microscopi-
cally monitored. The MIC and MFC were determined as above.
Toxicity tests with mice
Since origanum oil is known to be pungent and corrosive, a
titration of the doses of origanum oil was conducted to de-
termine the tolerable dose to be given orally. Both the neat
113
oil and the dilutions in olive oil (vehicle) were orally admin-
istered to the mice according to the body weight using a ball
tip gavage needle (Harvard Apparatus, South Natick, MA,
USA). Higher concentrations of the oil were given as single
bolus dose, while the lower concentrations were given daily
for 7 days. The overall health of the animals such as coat
color, body weight, other side effects such as scruffiness, and
death were recorded for 14 days. At the end of the experi-
ment, mice were sacrificed to visually examine the internal
organs for any abnormalities.
Effect on experimental murine systemic candidiasis
A murine systemic candidiasis model developed previously
[22], was employed to evaluate the in vivo anti fungal activi-
ties of origanum oil and carvacrol. Initially, the concentra-
tions of C. albicans needed to achieve 50% mortality of the
animals (LD50) were determined. Mice were injected i.v. with
varying doses of actively growing C. albicans in a final vol.
of 0.1 ml. Mortality of mice was monitored for 30 days. The
death of the mice due to C. albicans was confirmed by ana-
tomical evidence for organ involvement, i.e. the histological
presence of yeasts and/or pseudomycelia. Furthermore, re-
nal burden of C. albicans was assessed by culturing an ali-
quot of the kidney homogenate on S.g. agar plates. The dose
titration revealed that 2.5 × 106 C. albicans cells were needed
to kill 50% of the mice. Subsequently, batches of mice in-
jected with 5 × LD50 dose of C. albicans were used to assess
therapeutic activity.
Treatment protocol
In two separate experiments, groups of mice (6 each) in-
fected with C. albicans (5 × LD50) were gavaged, daily with
origanum oil or carvacrol in 0.1 ml of olive oil for 8 days
and 30 days. The amount of antifungal agents administered
was calculated based on the body weight of the mice. Con-
trol mice received either olive oil orally alone (negative
control), or olive oil orally plus amphotericin B 25 µg i.p.
(positive control). The experiments were terminated at the
end of 30 days. The body weights, the disease status and
the overall health of the mice during the experiment were
recorded. The pathological status of the mice was deter-
mined by visual examination of the internal organs after
their death or sacrifice at the completion of the experiment.
For histology, kidney smears were examined microscopi-
cally after staining with 1% methylene blue for the presence
of fungal elements. Renal burden of C. albicans was fur-
ther tested by culturing aliquots of kidney homogenates on
S.g. agar plates.
Results
Origanum oil is fungicidal to C. albicans in vitro
In the present study, we have examined the antifungal prop-
erties of origanum oil and one of its major constituents, car-
vacrol and thymol, both in vitro and in vivo. Using Candida
albicans in broth cultures and a micro-dilution method, com-
parative efficacies of origanum oil, carvacrol, nystatin and
amphotericin B were examined in vitro. Origanum oil at 0.25
mg/ml was found to completely inhibit the growth of C. al-
bicans in culture. Growth inhibitions of 75% and >50% were
observed at 0.125 mg/ml and 0.0625 mg/ml level, respec-
tively (Table 1). Figure 1 provides a pictorial presentation of
the inhibitory effect. A 2-fold higher concentration of carvac-
rol was required to be fungicidal.
Both the germination and mycelial elongation of C.
albicans are inhibited in vitro
Origanum oil and carvacrol both inhibit germ-tube formation
by the blastospores of C. albicans (Table 2). The production
of germ tubes and subsequent mycelial formation when ex-
posed to either serum or hen’s egg albumen is an in vitro
correlate of the in vivo tissue invasive capabilities of the
pathogenic strains of C. albicans. Origanum oil inhibited
Table1. Effect of origanum oil on the growth of Candida albicans
Agent 24 h MIC 48 h MFC
(mg/ml) (mg/ml)
Origanum oil 0.125 0.25
Carvacrol 0.25 0.5
Amphotericin B 0. 0015 0.0015
Nystatin 0. 005 0.005
Olive oil No effect No effect
MIC = minimum inhibitory concentration; MFC = minimum fungicidal
concentration.
Table 2. Effect of origanum oil on germ tube formation and filament elon-
gation
Agent Germ tube formation Filament elongation
MIC MFC MIC MFC
mg/ml mg/ml mg/ml mg/ml
Origanum oil 0. 062 0.125 0.125 0.125
Carvacrol 0. 125 0.125 0.125 0.25
Olive oil NE NE NE NE
NE = no effect; MIC and MFC for nystatin and amphotericin B = 2.5 and
5.0 µg/ml respectively.
114
germ-tube production by blastospores of C. albicans in a dose-
dependent manner. The MIC required to inhibit the production
of germ tube formation was 0.062 mg/ml (24 h) and the fun-
gicidal effect (at 48 h) required double the concentration
(MFC = 0.125 mg/ml). Carvacrol exerted effects similar to
origanum oil at twice the concentrations. Origanum oil and
carvacrol were also found to affect filament elongation. The
mycelial forms of C. albicans were also inhibited by origa-
num oil at 0.125 mg/ml (MIC) and 0.125 mg/ml (MFC) lev-
els, and by carvacrol at 0.125 mg/ml (MIC) and 0.25 mg/ml
(MFC) levels, respectively.
Origanum oil can protect mice from systemic candidiasis
The therapeutic efficacy of origanum oil was examined in an
experimental murine systemic candidiasis model. Toxicity
studies to determine the least toxic dose of origanum oil that
can be fed safely to mice were conducted (Table 3). A single
bolus dose of 650 mg/kg body weight caused uniform mor-
tality. However, daily administration of smaller doses of ori-
ganum oil mixed with olive oil was well tolerated, showing
no apparent clinical abnormalities (Table 3).
In the first in vivo study, the therapeutic ability of origa-
num oil given only for 8 days to prevent the mortality of mice
with systemic infection due to C. albicans was tested (Table
4). Groups of mice (n = 6) infected with C. albicans (5 × LD50)
were gavaged with varying amounts of origanum oil in a fi-
nal vol. of 0.1 ml. An 8-day treatment with 162.5 mg and 325
mg per kg body weight was found to rescue the mice from
mortality with 100% survival rate over the 30 days of obser-
vation, similar to mice that received amphotericin B (1 mg/
Fig. 1. In vitro antifungal activity of origanum oil against Candida albicans. Exponentially growing C. albicans cells were cultured with varying concentra-
tions of antifungal agents. Aliquots from the cultures drawn at the end of 48 h of culturing were plated on to Sabouraud’s glucose agar. The plates were
further incubated for an additional 48 h for the appearance of yeast like colonies.
Table 3. Toxicity of origanum oil to BALB/c mice
Concentration of oil* No. of mice
(mg/kg) (tested/survived)
Bolus dose 2600 5/0
1300 5/0
650 5/0
325.0 5/5
162.5 5/5
Daily dose for 1 week 26 6/6
52 6/6
78 6/6
104 6/6
130 6/6
*Oil was mixed with 100 µl olive oil and gavaged.
Table 4. Therapeutic efficacy of origanum oil: 8-day treatment
Agent Conc. @ per No. of mice No. of mice with
kg body wt. (mg) tested/survived renal burden#
Origanum oil 325. 5 6/6 4/6
162. 5 6/6 6/6
Amphotericin B 1. 0 6/6 2/6
Olive oil (vehicle) 6/0*
*Died within 10 days. #Renal burden+ = kidney smear+ culture+.
115
kg body weight). In contrast, the control group of mice who
received 0.1 ml of olive oil alone died within 10 days. At the
end of 30 days, the surviving animals appeared to be clinically
healthy, without scruffiness and with regain of normal coat
luster. Internally, no abnormalities of organs were noted. Fur-
thermore, the kidney smears failed to demonstrate the pres-
ence of either yeasts or pseudomycelia. However, the culture
of their kidney homogenates on S.g. agar revealed the pres-
ence of C. albicans. (Table 4).
The results from the second experiment to determine the
optimal dose over a 30-day treatment course required for
clinical cure and to completely eliminate the renal burden of
C. albicans are shown in Table 5. A daily administration of
origanum oil as low as 8.66 mg/kg body weight (equivalent
of 1 µl per mouse) was found to cure 80% of the infected
mice. Initially all groups of infected mice, exhibited scruffi-
ness, loss of body weight, and lack of coat luster. In the ve-
hicle-control mice, the average body weight was found to
decrease 7 days after injection from approximately 16–11 g.
In contrast, mice receiving treatment had a gradual increase
in body weight after injection from 15–17 to 16–19 g by the
end of 30 days (Fig. 2). The daily administration of equiva-
lent amounts (8.66 and 17.33 mg/kg body weight) of carva-
crol was found to confer similar therapeutic properties (data
not shown). However, the overall clinical appearance of the
mice receiving origanum oil was cosmetically better than
those receiving carvacrol, as evidenced by the improved coat
luster and minimal scruffiness.
Discussion
Aromatic herbal oils used for cooking and flavoring are in-
creasingly claimed to have broad spectrum antimicrobial
activities. Origanum oil has been suggested to have potent
antimicrobial activity, including anthelmintic properties, due
to its phenolic, alcoholic and terpenoid constituents [4]. The
objective of the present study was to assess the antifungal
properties of origanum oil against C. albicans in both in vitro
and in vivo. Furthermore, the comparative efficacy of origa-
num oil, carvacrol, nystatin and amphotericin B was also
examined. The results clearly demonstrate that the origanum
oil can act as a potent antifungal agent against C. albicans,
and can function similar to antifungal antibiotics such as
nystatin or amphotericin B.
C . albicans is a harmless commensal yeast-like fungus in
healthy humans, which can cause superficial as well as life-
threatening systemic infections under immune compromised
situations. C .albicans can colonize or infect virtually all body
sites because of its high adaptability to different host niches
by the activation of appropriate sets of genes in response to
complex environmental signals [21–25]. Thus, our objec-
tive was to assess the possible therapeutic potential of the
commonly used origanum oil against this human dimorphic
commensal, which can become a facultative pathogen un-
der altered physiological situations.
Previous studies to assess the inhibitory effect of origanum
oil against twenty-five different genera of microorganisms
including animal and plant pathogens, food poisoning and
spoilage bacteria, have demonstrated the growth inhibition
properties by origanum oil [26]. Essential oils of oregano
(Origanum vulgare) were found to inhibit the growth and
production of ochratoxin A by Aspergillus ochraceus NRRL
3174 up to 21 days in culture [27].
Origanum oil has been shown to delay or inhibit the growth
of saprophytic food spoiling fungi such as Aspergillus fla-
vus (mycotoxogenic) and industrial yeasts such as Hansenula
Table 5. Therapeutic efficacy of origanum oil: 30-day treatment
Agent Conc. @ per No. of mice No. of mice with
kg body wt. (mg) tested/survived renal burden#
Origanum oil 52. 00 6/6 0/6
43. 33 6/6 0/6
31. 00 6/6 0/6
26. 00 6/6 0/6
17. 33 6/6 0/6
8. 66 6/5 0/5
Carvacrol 17. 33 6/6 0/6
8. 66 6/5 0/5
Amphotericin B 1. 0 6/6 0/6
Olive oil 6/0* 6/6
*Died within 10 days. #Renal burden+ = kidney smear+ culture+. One mouse
treated with 8.66 mg origanum oil/kg b.w. died on day 15, while one mouse
treated with 8.66 mg carvacrol/kg b.w. died on day 13. Fig. 2. In vivo effect of origanum oil in experimental murine candidiasis.
Infected mice were fed orally with varying amounts of origanum oil in 0.1
ml vol. of olive oil (vehicle). The control animals received either olive oil
alone or olive oil plus amphotericin B (i.p.). The body weights and the
overall health of the mice were recorded daily.
116
anoma [8]. Furthermore, origanum oil, and carvacrol have
been reported to have some promising effect on rats infected
with a human dermatophytic fungus, Trichophyton rubrum
[10]. However, the essential oils including origanum oil at
100 ppm had no effect on the pseudomycelial formation by
Candida lipolytica [10,11].
In this paper we have demonstrated, that origanum oil ef-
fectively inhibits the in vitro growth of C. albicans, a human
yeast-like fungus which can cause both systemic and super-
ficial infections in debilitated individuals. In addition we have
shown that origanum oil directly inhibits germination and
filament formation (the two phases required for tissue inva-
sion) by C. albicans. Nevertheless, the novel fungicidal prop-
erty of origanum oil was of superior efficacy as compared to
carvacrol against the germination and mycelial elongation of
pathogenic strain of C. albicans in vitro. Furthermore, selected
concentrations of origanum oil demonstrated therapeutic ef-
ficacy comparable to the effective examined dose for am-
photericin B (1.0 mg) in protecting the mice from systemic
candidiasis. The overall clinical appearance of the mice re-
ceiving origanum oil was cosmetically better than those re-
ceiving carvacrol (data not shown), although this difference
in appearance could possibly be attributed to the presence of
additional constituent phenols such as thymol, terpenes and
flavonoids in origanum oil [4]. It has been demonstrated that
some of these components of origanum oil have antispas-
modic and antioxidant activities, in addition to their antimi-
crobial potentials [23, 28, 29]. A comparative study of these
components may shed more light not only on the antifungal
potentials, but also on the pharmacological effects of each of
these components. It is interesting to speculate that secondary
infections due to C. albicans in debilitated individuals such as
those having diabetes and HIV infection may be prophy-
lactically controlled by the daily intake of small amounts of
oregano oil, either alone or added to a food.
In summary, the results presented in this paper conclusively
demonstrate the antifungal potential of edible origanum oil.
Origanum oil is shown to be both fungistatic and fungicidal
to C. albicans, the human pathogenic yeast. Both the germi-
nation and the pseudomycelial phase of the yeast are inhib-
ited in vitro. Further, the daily oral administration of as little
1.0 µl of oil for 30 days completely freed 80% of the labora-
tory mice from experimental systemic candidiasis, which is
fatal if not treated. Thus, daily oral administration of origanum
oil may be highly effective in the prevention and treatment of
candidiasis. The results from our study not only encourage
examination of the efficacy of origanum oil in other forms
of systemic and superficial fungal infections, but also to ex-
plore its broad spectrum effect against other pathogenic
manifestations including malignancies.
Acknowledgement
This work was supported by a generous grant from North
American Herb and Spice located in Waukeegan, IL, USA.
Oreganum oil was a generous gift from the North American
Herb and Spice, Waukeegan, IL, USA.
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... Preus et al. (2005) studied the antimicrobial efficacy of several aromatic oils and reported that OEO was potent against two bacterial strains of Staphylococcus aureus, which are termed ATCC 14154 and ATCC 14775 [10]. The fungicidal properties of OEO have also been reported [11]. OEO is soluble in hydrophobic solvents, such as methanol and acetone. ...
Article
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Oregano essential oil was encapsulated in poly-ϵ-caprolactone nanoparticles by a nanoprecipitation method using glycerin as a moisturizer. Nanocapsule characterization was performed by measuring the particle size, colloidal stability and encapsulation efficiency using dynamic light scattering, UV–Vis spectrophotometry and scanning electron microscopy (SEM). The nanoparticles had a mean particle size of 235 nm with a monomodal distribution. In addition, a low polydispersity index was obtained, as well as a negative zeta potential of −36.3 mV and an encapsulation efficiency of 75.54%. Nanocapsules were applied to polyester textiles through bath exhaustion and foulard processing. Citric acid and a resin were applied as crosslinking agents to improve the nanocapsules’ adhesion to the fabric. The adsorption, desorption, moisture content and essential oil extraction were evaluated to determine the affinity between the nanocapsules and the polyester. The adsorption was higher when the citric acid and the resin were applied. When standard oregano nanocapsules were used, almost all of the impregnated nanoparticles were removed when washed with water. The moisture content was evaluated for treated and non-treated textiles. There was a significant increase in the moisture content of the treated polyester compared to the non-treated polyester, which indicates that the polyester hydrophilicity increased with an important absorption of the essential oil nanocapsules; this can improve fabric comfort and probably promote antibacterial properties.
... Cloves have been reported to have antiviral activity against strains of herpes virus, hepatitis C, and influenza A [3][4][5]; antimicrobial activity against Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Proteus vulgaris, and Streptococcus suis [6][7][8]; antifungal properties against Trichophytonrum rubella, Trichophytonrum mentagrophytes, Microsporum canis, Fusarium monoliforme, Fusarium oxysporum, Epidermophyton floccosum, Mucor sp., Microsporum gypseum, Candida albicans, and Aspergillus sp. [9][10][11][12][13][14]; and antiprotozoal activity against parasites of the genus Babesia and Theile-ria [2]. Additionally, the acaricidal activity of clove essential oil has been reported against Dermatophagoides pteronyssinus and Dermatophagoides farina [15]. ...
Article
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In the present study, the fungicidal and nematicidal activities of the hexanic and methanolic extracts of Syzygium aromaticum were evaluated. At a concentration of 100 µg/ml, the hexanic extract inhibited 43.70% of the mycelial growth of Fusarium sp. at 48 h and 52.90% at 72 h; while at the concentration of 200 µg/ml, it inhibited 54.30% and 60% of the mycelial growth of Fusarium sp. at 48 h and at 72 h, respectively. The methanolic extract inhibited 99.87% of the hatching of Haemonchus contortus (H. contortus) eggs at a concentration of 1.25 mg/ml, with respect to the mortality of J2 larvae of it was 71.11% at the concentration of 1.25 mg/ml. Gas Chromatography coupled to mass spectrometry analysis allowed the identification of 17 compounds in total, of which eugenol, acetyl eugenol and caryophyllene were the most abundant in both hexanic and methanolic extracts. Additionally, hexatriacontane, octacosane, 11, 11-Dimethyl-4,8-dimethylenebicyclo [7.2.0] undecan-3-ol, ledene oxide-(II), and humulene were only present in the methanolic extract, while isoaromadendrene epoxide, 2-naphthalenemethanol, decahydro-α, α, 4a-trimethyl-8-methyle, loxapine N-oxide, diepicedrene-1-oxide, aristolochic acid II, and trans-isoeugenol were only found in the hexanic extract.
... (2001) menunjukkan bahwa essential oil atau minyak atsiri dari daun oregano memiliki sifat fungistatik dan fungisidal terhadap pertumbuhan Candida albicans, didapatkan nilai kadar hambat minimum (KHM) 0,125 mg/ml dan nilai kadar bunuh minimum (KBM) 0,25 mg/ml menggunakan metode mikrodilusi. 18 Hasil penelitian Iuliana dkk. (2011) me nyatakan bahwa ekstrak daun oregano memiliki aktivitas antioksidan tertinggi dan kaya akan senyawa flavonoid. ...
Article
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Latar belakang: Candida albicans merupakan salah satu flora normal oral yang dapat menyebabkan infeksi pada rongga mulut manusia yang disebut sebagai kandidiasis. Manajemen primer yang sering digunakan dalam mengatasi kandidiasis pada rongga mulut salah satunya adalah nystatin, namun pemberian nystatin hanya terbatas pada pengobatan topikal infeksi kandidiasis kulit dan mukosa karena memiliki spektrum yang sempit dan penyerapan yang buruk pada saluran pencernaan serta memiliki efek samping pada dosis yang tinggi seperti mual ringan, diare, dan muntah. Masyarakat sering menggunakan daun oregano (Origanum vulgare L.) sebagai obat tradisional untuk mengobati berbagai macam penyakit seperti gangguan bronkial, gangguan pencernaan, gatal pada kulit dan flu.Sejumlah penelitian (secara in vitro dan in vivo) juga menunjukkan bahwa daun oregano (Origanum vulgare L.) mengandung beragam senyawa fitokimia seperti fenolik glikosida, flavonoid, tanin, sterol dan terpenoid dalam jumlah tinggi. Tujuan: Mengetahui kadar hambat minimum (KHM) dan kadar bunuh minimum (KBM) ekstrak etanol daun oregano (Origanum vulgare L.) terhadap pertumbuhan Candida albicans secara in vitro. Metode Penelitian: Penelitian ini bersifat eksperimental murni laboratorium secara in vitro dengan cara membandingkan kelompok sampel yang mengandung ekstrak etanol daun oregano dengan konsentrasi 50 mg/ml; 25 mg/ml; 12,5 mg/ml; 6,25 mg/ml; 3,125 mg/ml; 1,562 mg/ml; 0,781 mg/ml; serta kontrol negatif berupa DMSO (Dimethyl Sulfoxide) 10% dan kontrol positif berupa nystatin. Metode yang digunakan yaitu metode broth microdilution pada 96 well plate yang diamati dengan spektofotometri dan uji kadar bunuh minimum (KBM) dengan metode spread pada agar yang dihitung menggunakan colony counter. Hasil Penelitian: Ekstrak etanol daun oregano (Origanum vulgare L.) memiliki kadar hambat minimum (KHM) pada konsentrasi 0,781 mg/ml dan kadar bunuh minimum (KBM) pada konsentrasi 50 mg/ml. Kesimpulan: Ekstrak etanol daun oregano (Origanum vulgare L.) memiliki aktivitas antijamur terhadap pertumbuhan Candida albicans.
... Manohar ve arkadaşları, kekik yağının 0.25 mg/ml'de kültürdeki C. albicans gelişimini tamamen inhibe ettiğini göstermişlerdir. 0.125 mg/ml'de %75 gelişim inhibisyonu ve 0.0625 mg/ml'de >50% oranında bir gelişim inhibisyonu tespit etmişlerdir [29]. Araştırıcılar ayrıca origanum yağı ve karvakrolün, C. albicans'daki çimlenme ve miselyal gelişimini doz bağımlı olarak inhibe ettiğini göstermişlerdir. ...
Article
Candida species can cause superficial and systemic disease and their biofilms have become an important problem for both hospital-acquired and device-associated infections. The efficacy of many antifungal agents are limited by their cytotoxicity and increasing rate of drug-resistant. In last years, the antimicrobial and antibiofilm activity of some natural products such as essential oils have drawn attention. Carvacrol [2-methyl-5-(1-methylethyl)phenol] is one of the phenolic components of thyme and have strong antimicrobial activity. Thus far, limited reports have discussed the antimicrobial effects of carvacrol on clinical Candida strains. In our study, it was aimed to investigate the effects of carvacrol on clinical Candida isolates by microbiological and transmission electronmicroscopic methods and to investigate the effects of carvacrol on the fungal cell wall by immunoelectron microscopic method using the hyphal wall protein Hwp1 protein. In this study, 24 clinical isolates and 1 reference strain (C. albicans ATCC 14053) were used. The minimum inhibitory concentration (MIC) of carvacrol was determined using the broth microdilution method. MIC results showed a MIC ⩽ 0.031% (vol/vol) for all isolates tested. For transmission electron microscopic studies, isolates were also exposured to the carvacrol at concentration of 1⁄2 MIC for 48 hours and results were compared with the control. According to our results, carvacrol showed high antifungal potential with very low MIC values on Candida isolates. Electron microscopically, no growth was observed at the MIC value and the higher concentrations; cellular damage was also determined at sub MIC concentrations. It has been shown that carvacrol causes irreversible damage to cells. We observed that carvacrol did not increase cell growth or hyphal growth at all studied concentrations. The immunogold labeling results were used to observe the effect of carvacrol on the cell wall. Although immune labeling was greatly reduced in carvacrol treated cells, the presence of Hwp1 protein was also observed in the scattered cytoplasm. Usage of carvacrol in the topical treatment of Candida infections with further study it was determined that a potentially promising drug and detailed studies on the subject are needed.
... Per quanto riguarda le micosi, vengono prese in considerazione soprattutto infezioni mucosali o sistemiche da Candida spp. (Manohar, 2001;Mondello, 2003;Mondello, 2006;Chami, 2004;Chami, 2005;Wang, 2020) infezioni cutanee da dermatofiti (Tiwari, 2003;Sokovic, 2008;Pisseri, 2009; e da Malassezia spp. (Nardoni, 2014;. ...
Technical Report
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Natural substances and integrated therapies: food for thought from the seminars of the study group of Integrated Therapies and Natural Substances. Edited by Andrea Geraci, Anna Maria Marella, Francesca Mondello, Annarita Stringaro 2022, iv, 120 p. Rapporti ISTISAN 22/2 (in Italian), Istituto Superiore di Sanità. Natural products have a long history of use as drugs, drug precursors and/or adjuvants for the treatment of various pathological conditions and there are many examples of molecules derived from natural substances that have changed the history of medicine, along with the related Nobel Prize assigned. Interest in natural substances is growing progressively for cultural, scientific and economic reasons. Often some products of natural origin, in the commercial form of food supplements, are neither standardized nor studied for all their possible actions, both beneficial and adverse, and the enormous demand by the consumer of these products for “health-promoting use” is noted. This volume is intended to represent a popularizing tool of recent research presented in some seminars organized by the Study Group of Integrated Therapies and Natural Substances of the Istituto Superiore di Sanità (the National Institute of Health in Italy) to animate reflection on lights and shadows in the field of integrated therapies that involve the use of natural substances. Key words: Vegetable products; Phytotherapy; Integrative medicine
... The n-hexane fraction, composed mostly of essential oils, also had activity against Candida albicans, which was resistant to the crude extracts and most of the fractions, but exhibited little or no activity against other test pathogens (Fig 1, Fig 2 and Table 2). The antifungal activity of plants essential oils against Candida albicans have also been reported by Manohar et al., 21 . The phytochemical screening of the plant's crude extracts and the various fractions revealed the presence of saponins, tannins, glycosides, alkaloids, flavonoids, and oils in varying proportions (Table 3). ...
Article
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The antimicrobial activity of Pycnanthus angolensis (Welw) (stem bark) used in ethnomedicine to treat urinary tract infections, diarrhoea, malaria and typhoid fever was investigated. Clinical isolates of Klebsiella spp, Proteus mirabilis, and type isolates including Candida albicans ATCC 7596, Escherichia coli ATCC 11775, Pseudomonas aeruginosa ATCC 10145, Staphylococcus aureus ATCC 1200 and Salmonella kintambo SSRL113 were used in the study. Agar well diffusion and broth dilution techniques were used to determine the antimicrobial activity and minimum inhibitory concentration (MIC), respectively. The results showed that the plant's ethanol extract was more active than the aqueous plant extract. Fractionation of the ethanol extract with n-hexane, chloroform, ethyl-acetate, acetone and methanol was carried out to obtain corresponding fractions. Antimicrobial activity testing of the fractions showed that the ethyl-acetate fraction exhibited the highest antimicrobial effect. Phytochemical analysis of the crude extracts and the various fractions revealed the varied contents of alkaloids, saponins, essential oils, tannins, glycosides and flavonoids, which are or can be largely responsible for the recorded antimicrobial effect. Acute toxicity studies performed on the ethanolic extract using albino rats indicated that the extract is non-toxic (LD50>5000 mg/kg body weight).
... ATO BED BUG ® was efficient in controlling Alternaria solani. According to Manohar et al. (2001), the phenolic components of clove oil: eugenol and carvacrol possess fungicidal characteristics on the cellular membrane. Also, clove oil has shown an antifungal activity against Candida albicans and Trichophyton mentagrophytes (Tampieri et al., 2005). ...
Article
Full-text available
The increasing use of chemical insecticides has adversely effected the environment and increased insectresistance. Biopesticides have been noticed the potential to be an excellent alternative to chemicals to reduce thenegative impacts to human health and the environment. Tomato (Lycopersicon esculentum) is the second mostimportant vegetable crop worldwide due to its nu tritional importance. The ef fect of NOVOSECT SC21® (0.5L/200 L), ATO BED BUGS® (1 L/200 L) and NEO-BOOST® (1 kg/200 L) against Tuta absoluta, Liriomyzatrifolii and Alternaria solani was studied. A complete randomized block design (CRBD) was used with threereplications, three treatments and one control in Hrajel area in Lebanon in the summer of 2020. We evaluated thelevel of infestation and larval mortality level of Tuta absoluta, Liriomyza trifolii and Alternaria solani infection24, 48 and 72 hr after the application. Results showed that NOVOSECT SC21® (Mix of metabolites of theBacillus F.D. 777) was the most efficient in decreasing the infestation and inducing larval mortality level of T.absoluta and L. trifolii and the fungal infection induced by A. solani with significant difference with time,followed respectively by ATO BED BUGS® and finally NEO-BOOST®.
Thesis
Nowadays, one of the major problems in agriculture remains the struggle against pathogens, especially fungi. In the last 60 years, the use of large amounts of pesticides to increase crop yield caused environmental pollution, loss of biodiversity, and the development of multi-resistant plant pathogens. Now, more than ever, agriculture practises must become environmentally friendly and thus, new strategies to improve agriculture, without side effects for the environment and human health, need to be developed. Antimicrobial photodynamic treatment (APDT) has emerged as an alternative treatment that can be envisaged in agronomic practices to fight against microorganisms, without harming plants. To develop this approach on complex living systems such as grapevine and potato, hosts of the fungus pathogen Botrytis cinerea and two photosensitizers were taken into consideration: an anionic porphyrin (TPPS) and a natural chlorin Chlorophyllin (Chl). More specifically, an extensive work was conducted using photoactivated TPPS. TPPS was very effectively inhibit Botrytis cinerea development and it did not cause any phenotypical or biochemical alterations of the grapevine varieties (Merlot, Chardonnay and Sauvignon). In the potato varieties, while there were alterations in its growth and development, the plants were able to defend themselves. Furthermore, in order to find a new eco-friendly solution that is more suitable for a large range of plants we tested a natural PS: the chlorophyllin (Chl). Surprisingly, Chl was able to inhibit Botrytis cinerea mycelium growth without disturbing neither potato nor grapevine plantlet growth. In conclusion, these preliminary studies based on the use of Chl suggest that the development of a safe but efficient APDT approach in agriculture may no longer be a dream
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A candidíase é uma infecção fúngica provocada pela Candida, leveduras que coloniza habitualmente a pele e a mucosa humana. Acomete homens e mulheres, principalmente, em idade fértil e o tratamento clássico envolve desde o uso de pomadas antifúngicas até a escolha do material das roupas do paciente. A presente revisão teve como objetivo apresentar demais estudos que trazem dados acerca da intervenção na dieta de pacientes com quadro de candidíase, como aliado no tratamento clássico a candidíase e candidíase por repetição, bem como o uso de cepas para corrigir o estado disbiótico e obter uma resposta definitiva a condição, já que o sucesso do tratamento depende da resposta imunológica e tal resposta está diretamente ligada a condição da microbiota intestinal do indivíduo. Para tal análise foram feitas buscas por artigos em bases eletrônicas como PubMed, BIREME e SciELO. Os resultados mostraram os benefícios de uma dieta equilibrada, com restrição de carboidratos, ultraprocessados e os benefícios da administração de probióticos como os Lactobacillus e Bifidobactérias.
Article
Background Clostridioides difficile is the most common causative agent of antibiotic-acquired diarrhea in hospitalized patients associated with substantial morbidity and mortality. The global epidemic of CDI (Clostridioides difficile infection) began in the early 20th century with the emergence of the hypervirulent and resistant ribotype 027 strains, and requires an urgent search for new therapeutic agents. Objective The aim of this study is to investigate the antibacterial activity of the three essential oils isolated from spice herbs (wild oregano, garlic and black pepper) against C. difficile clinical isolates belonging to 6 different PCR ribotypes and their potential inhibitory effect on the biofilm production in in vitro conditions. Results Wild oregano essential oil showed strong inhibitory activity in concentrations 0.02–1.25 mg/mL and bactericidal activity in concentrations from 0.08 to 10 mg/mL. Garlic essential oil was effective in the concentration range of 0.02–40 mg/mL, and 0.16 - > 40 mg/mL. MIC and MBC for black pepper oil ranged from 0.04 to 40 mg/mL, and 0.08 - > 40 mg/mL, respectively. All the tested oils reduced in vitro biofilm production, with the best activity of oregano oil. Conclusion Essential oils of wild oregano, black pepper and garlic are candidates for adjunctive therapeutics in the treatment of CDI. Oregano oil should certainly be preferred due to the lack of selectivity of action in relation to the ribotype, the strength of the produced biofilm and/or antibiotic-susceptibility patterns.
Book
The World Health Organization estimates that at least five million people worldwide are infected with human immunodeficiency virus (HIV) Of these about 100,000 are in Asia and Oceania, 500,000 in Europe, 2 million in the Americas and 2.5 million in Africa (Mann, 1989). The acquired immunodeficiency syndrome is characterized by a derangement in cell-mediated immunity leading to opportunistic infections with for example Mycobacterium spp., Candida spp., Cryptococcus neoformans, Pneumocystis carinii, Toxoplasma gondii and Cryptosporidium. The third symposium on "Topics in Mycology" brought together 265 experts from 32 countries to discuss the epidemiology, immmunological and pathogenetic aspects of AIDS and its opportunistic infections in general and fungal infections in particular. Pneumocystis carinii pneumonia is by far the commonest opportunistic infection in AIDS patients. The nature and classification of P. carinii is still controversial. In search for its true taxonomic affinities an introductory paper formulates a number of key questions. Candidosis is another frequent opportunistic infection. A number of papers discuss the possibility that selective pressures may operate on Candida albicans within the AIDS population and influence its nature: this might have an impact on prophylaxis and curative and/or suppressive therapy.
Article
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.
Article
The essential oils of Origanum vulgare subsp. hirtum, Mentha spicata, Lavandula angustifolia, and Salvia fruticosa exhibited antifungal properties against the human pathogens Malassezia furfur, Trichophyton rubrum, and Trichosporon beigelii. Of the four oils, O. vulgare subsp. hirtum oil showed the highest fungicidal activity and at a dilution of 1/50000 caused a 95% reduction in the number of metabolically active cells within 6 h of exposure. Among the main components of the four oils, carvacrol and thymol exhibited the highest levels of antifungal activity. The therapeutic efficacy of the O. vulgare subsp. hirtum essential oil was tested in rats experimentally infected with T. rubrum and yielded promising results. Furthermore, the above essential oils were tested with the Ames test and did not exhibit any mutagenic activity. Keywords: Essential oils; Origanum vulgare; Mentha spicata; Lavandula angustifolia; Salvia fruticosa; Malassezia furfur; Trichophyton rubrum; Trichosporon beigelii; Dermatophytosis; antifungal; mutagenic; in vivo studies
Article
Thirty-two essential oils from plants were screened for inhibitory effects on 13 food-spoilage and industrial yeasts. Of these, essential oils of allspice, cinnamon, clove, garlic, onion, oregano, savory, and thyme were most inhibitory. Oils were subsequently tested for their effects on biomass production and pseudomycelium formation of eight genera of yeasts. Garlic oil was a potent inhibitor of yeast growth at concentrations as low as 25 ppm. The oils of onion, oregano and thyme were also strongly inhibitory. Essential oils (100 ppm) had no effect on pseudomycelium production by Candida lipolytica. However, all eight essential oils delayed pseudomycelium formation by Hansenula anomala, whereas six oils stimulated pseudomycelium production by Lodderomyces elongisporus. Cinnamon and clove oils were clearly stimulatory to pseudomycelium production by Saccharomyces cerevisiae.
Article
The essential oil composition of Cananga odorata, Boswellia thurifera, Cymbopogon citratus, Marjorana hortensis, Ocimum basilicum, Rosmarinus officinalis, Cinnamomum zeylanicum and Citrus limon was analysed by GC and GC–MS, and their antimicrobial and antioxidant activity tested. Twenty-five different genera of bacteria and one fungal species were used in this study as test organisms. These included animal and plant pathogens, food poisoning and spoilage bacteria and the spoilage fungus Aspergillus niger. The volatile oils exhibited considerable inhibitory effect against all the tested organisms. The oils also demonstrated antioxidant capacities, comparable with α-tocopherol and butylated hydroxytoluene (BHT). The method adopted in this study was the modified thiobarbituric acid reactive species (TBARS) assay. The antioxidant activity was carried out under different conditions by using egg yolk and rat liver in the absence and presence of the radical inducer 2,2′-azobis (2-amidinopropane) dihydrochloride (ABAP). © 1998 John Wiley & Sons, Ltd.
Article
The X-ray structure of Escherichia coli TEM1β-lactamase has been refined to a crystallorgphic R-factor of 16.4% for 22,510 reflections between 5.0 and 1.8 Å resolution; 199 water molecules and 1 sulphate ion were included in refinement. Except for the tips of a few solvent-exposed side chains, all protein atoms have clear electron density and refined to an average atomic temperature factor of 11 Å2. The estimated coordinates error is 0.17 Å. The substrate binding site is located at the interface of the two domains of the protein and contains 4 water molecules and the sulphate anion. One of these solvent molecules is found at hydrogen bond distance from S70 and E166. S70 and S130 are hydrogen bonded to K73 and K234, respectively. It was found that the E. coli TEM1 and Staphylococcus aureus PC1 β-lactamases crystal structures differ in the relative orientations of the two domains composing the enzymes, which result in a narrowed substrate binding cavity in the TEM1 enzyme. Local but significant differences in the vicinity of this site may explain the occurrence of TEM1 natural mutants with extended substrate specificities. © 1993 Wiley-Liss, Inc.
Article
Spices and herbs are recognized as sources of natural antioxidants and thus play an important role in the chemoprevention of diseases resulting from lipid peroxidation. Our studies on spices and herbs have given us over a hundred compounds, known and new, having high antioxidant activity. From the Labiatae family, Rosmarinus officinalis, Thymus vulgaris, Origanum vulgare and O. majorana gave 26 active comopounds. Over 40 antioxidative compounds from Zingiber officinale, 26 compounds from Curcuma domestica = C. longa, C. xanthorrhiza and Z. cassumunar were determined, these belonging to the family Zingiberaceae. From the family Myrtaceae, 25 compounds from the berries of Pimenta dioica were determined and 3 carbazoles were isolated from Murraya koenigii. Structure-activity relationships of some of the isolated compounds were also discussed.
Article
In addition to the spasmolytic activity of ORIGANUM COMPACTUM, the antagonistic effect of the main components thymol and carvacrol is investigated on the isolated guinea-pig ileum, induced by carbachol, histamine, 1,1-dimethyl-4-phenylpiperazinium iodide and BaCl (2). The l-noradrenaline contractions on the rat vas deferens are also reduced by both of phenols and the Origanum macerate. pD' (2) values and relative potency to papaverine illustrate the affinity of the isomers. It is concluded that thymol and carvacrol act as non-competitive antagonists and are not significantly different from each other.