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Nigella sativa and its active constituent thymoquinone in oral health

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Abstract

In this review, we summarized published reports that investigated the role of Nigella sativa (NS) and its active constituent, thymoquinone (TQ) in oral health and disease management. The literature studies were preliminary and scanty, but the results revealed that black seed plants have a potential therapeutic effect for oral and dental diseases. Such results are encouraging for the incorporation of these plants in dental therapeutics and hygiene products. However, further detailed preclinical and clinical studies at the cellular and molecular levels are required to investigate the mechanisms of action of NS and its constituents, particularly TQ. © 2016, Saudi Arabian Armed Forces Hospital. All rights reserved.
Nigella sativa and its active constituent thymoquinone in
oral health
Safia A. AlAttas, MS, FAAOM, Fat’heya M. Zahran, MS, PhD, Shereen A. Turkistany, BD, MS.
235
ABSTRACT
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In this review, we summarized published reports
that investigated the role of Nigella sativa (NS) and
its active constituent, thymoquinone (TQ) in oral
health and disease management. e literature studies
were preliminary and scanty, but the results revealed
that black seed plants have a potential therapeutic
effect for oral and dental diseases. Such results are
encouraging for the incorporation of these plants in
dental therapeutics and hygiene products. However,
further detailed preclinical and clinical studies at the
cellular and molecular levels are required to investigate
the mechanisms of action of NS and its constituents,
particularly TQ.
Saudi Med J 2016; Vol. 37 (3): 235-244
doi: 10.15537/smj.2016.3.13006
From the Department of Oral Diagnostic Sciences (Al-Attas, Zahran),
Faculty of Dentistry, the Centre of Innovation in Personalized
Medicine (Turkistany), King Abdulaziz University, Jeddah,
Kingdom of Saudi Arabia.
Address correspondence and reprint request to: Professor Safia A.
AlAttas, Department of Oral Diagnostic Sciences, Faculty of Dentistry,
King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia.
E-mail: salattass@kau.edu.sa
Review Articles
www.smj.org.sa Saudi Med J 2016; Vol. 37 (3)
Currently there is a worldwide growing interest
on the use of medicinal herbs or plants in the
treatment of various diseases due to their promising
results and fewer side effects.1 According to the World
Health Organization (WHO), 60-80% of the world’s
population particularly in developing countries,
depends on herbal remedies or traditional medicine
for their primary health care and treatment. Moreover,
the WHO has encouraged developing countries to use
their medicinal plants as a resource to generate effective
health care programs.2,3 One of the top ranked evidence-
based herbal medicines, which has been described as the
“miracle herb of the century is Nigella sativa (NS).3,4
Nigella sativa is an annual flowering plant in the family
Ranunculaceae (Table 1) also called black cumin, black
seed, or Habbatul Barakah is native to the south and
southwest Asia, and is cultivated in several countries in
the Mediterranean region, South Europe, Syria, Turkey,
and Saudi Arabia.5,6 Historically, ancient Egyptian and
Greek physicians used NS seeds in the management
of several diseases, such as headache and toothache,
congestion of the nose, intestinal worms, promotion of
menstruation, and production of milk.7,8 e black seed
has a spiritual and religious impact in many Muslim
populations, as the prophet Mohammad said “use the
black seed regularly because it is a cure for every disease,
except death,’which could explain its extensive use by
millions of Muslims all over the world.9
Researchers have attributed the health promoting
benefits of the black seed to its active components and
high nutritional content.3 e seeds are composed of
28-36% fixed oils, proteins, alkaloids and saponins,
and 0.4-2.5% essential oils. Many pharmacologically
Disclosure. Authors have no conflict of interest and the
work was not supported or funded by any drug company.
is work was funded by the Scientific Research Council
(Project Code 2-165-35-RG), King Abdulaziz University,
Jeddah, Kingdom of Saudi Arabia.
OPEN ACCESS
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active compounds have been isolated from black
seeds, but the most reported active constituents are
thymoquinone (TQ), dithymoquinone, thymol, and
thymohydroquinone. Several nutritional components
are found in the seeds, such as carbohydrates, fats,
essential amino acids and vitamins. e seeds are
also considered to be a source of potassium, calcium,
and iron.4,8 Several authors have extensively reviewed
NS and its active component, TQ, and found them
to have many pharmacological properties, such as:
antimicrobial (antibacterial, anthelmintic, antifungal,
and antiviral); anti-inflammatory; analgesic; histamine
release inhibitor; antihypertensive; hypoglycemic;
anticarcinogenic; antioxidant; and hepatoprotective
among others.3,5,6 Oral health and the integrity of the
oral cavity are crucial to the general health of human
beings. Many oral diseases are preventable, and for
many years, the use of plants, oral health care, and
therapeutic practices have been closely related.10-12 A
literature review revealed that studies relating NS to oral
health are scant, and as of this date, no published report
summarizes their findings. e aim of this report is to
summarize the published studies on the role of NS and
its active component, TQ, in oral health.
PubMed and Google Scholar were used for
data search, and up-to-date papers in English were
selected using the following key words: Nigella sativa,
thymoquinone, oral health, dental health, periodontal
diseases, caries, pulp treatment, oral cancer, and oral
squamous carcinoma. e collected data are presented
in subheadings related to oral health issues.
Dental caries. Dental caries or tooth decay is
a progressive, irreversible microbial disease that is
characterized by bacterial fermentation of carbohydrates
resulting in acid production, and the subsequent
destruction of the hard tissues of the tooth. Streptococcus
mutans (S. mutans) and Streptococcus sobrinus are
the major suspected pathogens in the initiation and
progression of dental caries.13-15 According to a WHO
report, dental caries affect nearly all adults at some
point in their life.16 It remains a health problem and
a challenging disease inspite of the worldwide public
health strategies that have focused on preventive
methods, such as water fluoridation, and application of
topical fluorides.13 Recently, some authors investigated
the preventive effect of natural products on dental
caries.17,18 Although many authors believed that NS
and TQ might have a role in caries prevention because
of their antibacterial properties, there have been few
published studies on this topic. Only one study13 was
found with a rat experimental model, its aim was to
investigate the effect of NS on caries initiation through
the inhibition of microbiome formation. In that
study,13 the animals were challenged with S. mutans
and fed a diet rich of sucrose. e results showed that
the rats’ treatment with 10 mg of TQ per body weight
(in kg) in oral gel or drinking water statistically reduced
the caries score (p=0.02) and plaque index (p=0.01)
in comparison with the control groups. e authors
attributed the decrease in dental caries to the microbial
biofilm inhibition properties of TQ.13
Streptococcus mutans remain the major pathogen in
dental caries. Its pathogenicity is due to the production
of extracellular polysaccharides and its ability to bind
dental tissues through a biofilm and subsequent plaque
formation.15,19 e microbiome is composed of salivary
glycoproteins, bacteria (cocci, bacilli, and filamentous
forms) and their metabolic end products arranged in
a matrix of extracellular material. Dental microbiome
accumulates on and adheres to the teeth, restorations
and prosthetic appliances in the mouth, and plays an
important role in oral and dental diseases.20 Natural
products have recently been investigated as promising
alternatives to synthetic antimicrobial drugs, including
herbal products, such as NS and TQ.1,12,13,18,21-23
Harzallah et al18 carried out a research to assess the
anticariogenic activity of the Tunisian NS essential
oil and its TQ. ey used the method of broth
microdilution to evaluate the minimum inhibitory
concentration (MIC) of the NS essential oil and its TQ
for oral cariogenic pathogens. Surprisingly, they found
that 2.43 mg/disc essential oil contained only 3.35 μg/
ml TQ, and showed more antimicrobial activity than the
pure TQ compound (150 μg/disc). e latter was active
against all of the studied strains, especially S. mutans,
which showed inhibition zones of 24.5 ± 0.71 mm, and
Streptococcus mitis (S. mitis) with 22 ± 1.41 mm. ey
explained the antibacterial effect of NS essential oil,
even with a minimal amount of TQ, as being caused by
its other more potent bactericidal components, such as
p-cymene, limonene, and apinene.18 e black seed oil
extracts were not only found to have a bactericidal effect
Table 1 - Scientific classification of Nigella sativa.8
Kingdom Plantae
Subkingdom Tracheobionata, that is, vascular plant
Supervision Spermatophyte
Order Ranunculales
Family Ranunculaceae-butter cup family
Genera Nigella
Species N. sativa
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against S. mutans but also to have an effect on inhibiting
the adherence of S. mutans to the surface of the teeth.
Abd-Awn et al1 conducted a research using an agar
diffusion test followed by a minimum bactericidal
concentration (MBC) determination to test the NS oil
extract’s sensitivity to S. mutans and its ability to inhibit
bacterial adherence to the dental plaque compared with
chlorhexidine gluconate. e results showed that the
black seed oil extract has 10% MBC against S. mutans.1
However, the authors recommended that further
studies with different types of extracts (including
those from different regions) be evaluated for the
antibacterial activity of the black seed. In addition, they
recommended an analysis of the extracts for their active
ingredients, which are responsible for their antibacterial
activity. ey also cited the urgent need for finding a
standard method for extract preparation.1 e last point
was found to be valid, as Mohammed24 evaluated 2
different extracts of NS against 2 cariogenic bacteria,
S. mutans and S. mitis. e results demonstrated that
the inhibition zone for the ethanol extract was 12.7 mm
against S. mutans, and 10.4 mm against S. mitis, while
the inhibition zone for the ether extract was 6.3 mm
against S. mutans, and 5.1 mm against S. mitis. is
means that methanol extraction had a stronger effect
against the bacteria than did the ether extract.24
Periodontal and gingival diseases. Periodontitis is
microbiome-related dental inflammation caused by
Gram negative bacteria, resulting in connective tissue
destruction beyond the gingiva around the teeth.25,26
Almost 200 systemic diseases are connected to oral
health according to the American Dental Association.27
Periodontitis alone was found to have an established
association with several systemic conditions, such
as diabetes mellitus, cardiovascular and pulmonary
diseases, low birth weight, and other conditions.28,29 As
for dental caries, proper oral hygiene and microbiome
control are also very important strategies for periodontal
disease prevention. However, most of the population
does not perform proper mechanical microbiome
control due to lack of motivation or dexterity.30 e
regimen of periodontal treatment often includes the use
of antibacterial agents, which can reach diseased sites
systemically, or topically. A recent systematic review
showed that mouthwashes containing chlorhexidine
present high antiplaque (mean reduction of 40%),
and antigingivitis efficacy (mean reduction of 28%),
however, their adverse effects (such as, teeth and soft
tissue staining) limit their use.31 Many herbal products
have been used as alternatives to these synthetic drugs.20
Because of the antibacterial, anti-inflammatory, and
antioxidative properties of NS and TQ, the authors
believe that these products could have a role in
periodontal disease.32 In the rat model proposed by
Al-Wafi et al,13 besides the anti-caries assessment, an
evaluation of the potential preventive role of TQ on
gingival inflammation was conducted. e results
revealed that rats treated with TQ in drinking water or
an oral gel had statistically significant lower periodontal
indices and subgingival bacterial counts in comparison
with both the negative and positive control groups.
Additionally, their mandibular tissues, which were taken
for histological examination to determine the degree of
inflammation, demonstrated no signs of inflammation
compared with the controls. Another in vivo study,32
also in a rat periodontitis model, investigated the
preventive role of TQ in periodontal inflammation
initiation and progression. In that study,32 the gingival
margins of the rats’ molars were ligated with a 4/0 silk
suture to induce periodontitis. e experiment included
24 rats that were randomly and equally distributed into
3 groups; nonligated (NL), ligature only (LO), and
ligature plus daily treatment (TQ at 10 mg/kg). On day
11, the animals were sacrificed and in each group the
alveolar bone levels of molars were clinically measured
and examined histopathologically. e results revealed
that there were statistically significant higher bone
losses in the LO group in comparison with the NL and
the TQ groups. e same was reported regarding the
ratio of inflammatory cell infiltration to osteoclasts.
However, the reverse was true regarding the osteoblasts,
which showed significant lower activity in the LO
group than in the NL and TQ groups. us, it was
concluded that the oral administration of TQ helped
in periodontal disease prevention as it diminished
alveolar bone resorption.32 Additionally, a clinical
randomized single-blind split-mouth trial26 was carried
out to evaluate the effectiveness of a TQ-impregnated
periodontal chip in chronic periodontitis. e study
included the periodontal pockets of 12 male patients
with chronic periodontitis. ey were distributed
into 3 groups: control (no treatment), plain chitosan
chips, and TQ chips.26 Interestingly, the results showed
significant gains in the clinical attachments in the TQ
groups compared with the other groups. Al-Bayaty et
al26 advised the use of TQ chips in chronic periodontitis
patients as an adjunctive treatment during the scaling
and root planing, or for maintenance visits.
Pulpal diseases. Intracanal antisepsis is considered
to be one of the fundamental steps in root canal
therapy. Antimicrobial irrigating solutions and other
locally used disinfecting agents and medicaments play
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a key role in the eradication of microbes.33 An ideal
root canal irrigant should have high efficacy against
microorganisms in biofilms while being systemically
nontoxic and noncaustic to periodontal tissues.34
Although current irrigation regimens using sodium
hypochlorite (NaOCl) exhibit excellent antimicrobial
activity, caustic, and toxic effects to vital tissues are
often noted. erefore, there is a need for agents
that are both antibacterial and that exert minimal
tissue irritation. Plant-derived products represent a
rich source of antimicrobial compounds, and some
have been incorporated into oral hygiene products.
However, their application in endodontics is less well
documented.35 Only 2 studies33,36 have been found to
evaluate the possible use of NS or TQ in endodontics.
One study33 evaluated the antibacterial action of NS
with 5 different concentrations of aluminum potassium
sulfate (alum), Salvadora persica (Siwak), and a
combination of all these on root canal bacteria isolated
from 20 patients. e authors33 found that all 3 tested
herbs had bactericidal effects, and that the NS aqueous
extract (100% concentration) showed maximum
inhibition zones of 26 mm in diameter for Enterobacter
cloacae, 22 mm in diameter for Streptococcus oralis, 21
mm in diameter for Streptococcus anginosus, 20 mm in
diameter for Staphylococcus epidermides, and 16 mm in
diameter for Enterobacter cloacae, Streptococcus oralis,
Streptococcus anginosus, Staphylococcus epidermides and
Enterococcus durans. Another study36 searched for a new
capping medicament in pediatric dentistry to replace
formocresol because of its reported side effects. e
study compared the histopathological pulp response
to NS oil and formocresol (FC) in dogs. e results
showed that NS specimens histologically revealed mild
to moderate vasodilatation with few inflammatory cells
and a continuous odontoblastic layer. On the other
hand, FC specimens showed advanced inflammation
with severe vasodilatation and inflammatory cell
infiltration and degeneration. us, application of NS
maintained the vitality of the pulp, which makes it a
good pulpotomy agent in clinical practice.36
Oral ulcerations, oral mucositis and wound healing.
Oral ulcerations are common painful lesions that are
related to various conditions ranging from minor
local trauma to significant systemic conditions, such
as hematological, gastroenterological, dermatological,
and immunological diseases and malignancies.37,38
Topical NS oil was found to have a good therapeutic
effect on the healing of chemically induced oral ulcers.
Al-Douri and Al-Kazaz39 carried out an experiment on
12 rabbits. e authors created the ulcers with 0.3 ml
of 1% formalin injections in the cheek mucosa of the
rabbits followed by topical application of NS twice a
day for 3 days. e animals were sacrificed on the
fifth day, and their cheek mucosae were histologically
examined. e results showed a significant healing
process enhancement with NS treatment, and a marked
anti-inflammatory activity and differences in the rate of
epithelization between the NS and control groups. e
authors justified the results by asserting that the NS oil
accelerated the healing of ulcers, because it inhibited the
growth of pathogenic organisms at the site of the ulcers,
which could retard the healing process. Moreover, the
TQ flavonoids and the other components in the NS oil
(vitamins and minerals) make it an excellent promoter
of ulcer healing.39
Oral mucositis due to chemotherapy and radiotherapy
represents a problematic side effect in cancer treatment.
A study in a rat model evaluated the capacity of NS
to decrease the severity of chemotherapy-induced
mucositis.40 In that study,40 25 male albino rats were
divided randomly into 3 groups: control, untreated, and
treated. An intraperitoneal injection of 5 fluorouracil
(5FU) was used to induce mucositis in rats, and their
cheek pouches on the right side were scratched with a
wire brush to induce mucositis. Rats in the untreated
group received oral physiologic saline, and those in the
treated group were gavaged daily with 1 ml of NS seed
extract (400 mg/kg). Rats were sacrificed on day 14,
and the cheek pouch areas were excised and prepared for
histological and immunohistochemical analysis using
Bcl2 and PCNA immune labelling. e results showed
that in comparison with controls and 5FU untreated
rats, NS decreased the histologically observed damage
of the cheek mucosa in the mucositis model. e results
suggested NS as a promising prophylactic adjunct to
conventional chemotherapy for reducing the severity of
oral mucositis.40
Despite reports on the accelerated healing process
and scarless wounds in the oral cavity, in contrast to
wounds on the skin, healing oral wounds remains a
challenge due to the continuous saliva flow, and the
presence of microorganisms that tend to interrupt and
slow down the healing process. An in vitro study41
investigated the wound healing promoting properties of
4 aqueous extracts of Asian traditional medicinal plants:
NS, Melastoma malabathricum, Pluchea indica, and
Piper sarmentosum. e in vitro scratch assay was used
to assess the effect on wound healing activity, while the
extracts’ effect on collagen synthesis by human gingival
fibroblasts (HGF) was determined by hydroxyproline
levels. e NS extract (NSE) showed a significant
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enhancement of HGF proliferation compared with
other extracts and accelerated wound closure despite its
lack of significant effect on collagen synthesis.41
Bone healing/socket and implants. Recently, it has
been reported that black seed induced bone healing
in extracted teeth sockets and manifested faster bone
trabeculae formation.42 is was an animal study,42
in which the therapeutic effect of both powder and
oil forms of NS on socket healing were investigated.
e sample included 24 male New Zealand rabbits.
e researchers extracted the rabbits’ incisors, filled
the extraction sites with NS powder or oil material,
and compared the healing with the other side of the
mouth (control group).42 e extraction sites were
examined radiographically and histologically after one,
and 6 weeks. e results showed an early detection of
osteoid formation at the first week and bone trabeculae
formation at the 6th week in sockets treated with NS
(powder and oil). However, in the histological study,
it was found that at the extraction sites, NS powder
was more effective than the NS oil in terms of bone
formation.42 ey attributed this result to the complete
absorption of the powder compared with the oil, which
was applied with a piece of cotton for only 5 minutes
and then removed.42
Natural plants were proposed as a coating
agent because the biological molecules improve
osseointegration in dental implants.43 However,
the literature concerning NS and bone healing is
contradictory. A disappointing study was conducted
by El-Sweify et al44 to identify the effect of calcium
hydroxide powder mixed with NS oil compared with
bioglass on the healing of mandibular bone defects in
rats. e experiment included 40 albino rats that were
subjected to surgical procedures to induce a mandibular
surgical defect and were distributed into 4 groups.
Group I was the control group, where the bony defects
were left empty; Group II had bony defects that were
filled with calcium hydroxide powder mixed with saline;
Group III had bony defects that were filled with calcium
hydroxide mixed with NS oil; and Group IV had bony
defects that were filled with ready made bioactive glass
particulates. After 3 weeks, one half of the animals were
sacrificed, while the other half was sacrificed after 6
weeks. e results revealed that all of the used materials
were biocompatible with the animal model, but the
bioglass seemed to have the highest osteoconductive
and osteostimulatory effects among the materials used.
ere was no bone formation in Groups I, II, and III
after 3 and 6 weeks. Group IV after 3 weeks showed
only minute amounts of osteoid tissues; however, after
6 weeks, more fibrous tissues were seen, and the borders
of the defects were of normal thickness, and were
smooth and lined by a well-defined osteoblastic layer.44
On the other hand, an in vivo study43 was conducted
to investigate the black seed oil extract’s effect on the
bone implant interface’s mechanical and histological
properties. In the experiment, 12 New Zealand rabbits
received 4 screw-shaped (84 CpTi) implants in the tibiae
bone. e implants were divided into 2 groups; coated,
and uncoated with black seed oil extract. e results
showed that over different periods of time, the coated
implants had significantly better torque resistance than
the uncoated implants, and histologically revealed early
osseointegration with an osteophilic surface, as well as
no adverse tissue reaction.43
Microbial diseases. A) Antibacterial activity. ere
have been many studies that have investigated the
antimicrobial effect of NS, but they are not in the scope
of this review, although a few are mentioned. Currently,
there is an urgent need for new antibacterial drugs to
overcome the emergence of oral bacterial resistance.
Interestingly, an in vitro study22 was carried out to assess
the TQ’s inhibitory and resistance-modifying ability
against a panel of pathogenic bacteria, including oral
isolates. e results revealed that TQ demonstrated a
selective antimicrobial property; it was effective against
Gram positive bacteria, but Gram negative bacteria were
resistant to it.22 However, there was a 4-fold potential
effect of tetracycline and benzalkonium chloride (BC)
against the tested pathogens. us, TQ can be used in
multidrug resistant infections.22
More recently, a laboratory study45 was conducted
to compare the antibacterial effect of NS oil extract
with nanosilver and amoxicillin using the disk
diffusion method on oral S. mutans and S. sanguis.
e results showed that the NS oil at a concentration
of 330 mg/mL, demonstrated an inhibitory zone of
22 mm for S. mutans, and 9.75 mm for S. sanguis.
Meanwhile, the bacterial inhibitory zone of each of
the nanosilver concentrations at 3500 ppm and the
standard amoxicillin disc (25 μg) was 33.5-19.75 mm
for S. mutans and 11-21.75 mm for S. sanguis.45 us,
nanosilver had the highest antibacterial activity against
both bacterial strains, while NS and amoxicillin had a
similar effect on S. mutans and NS was more effective
than amoxicillin against S. sanguis.45
B) Antifungal activity. Oral candidiasis is a common
infection in the oral cavity caused by fungi, mostly
Candida albicans.46 Amphotericin B and triazoles, such
as fluconazole and itraconazole are the most common
antifungal agents that have been used systemically, or
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topically for fungal infections. Unfortunately, with a
prolonged course of therapy, fungal resistance erupts
as a challenge. Again, the medicinal plants have been
attractive to scientists as possible alternative fungal
treatments.47-50
In Hail province, a study50 assessed the in vitro
inhibitory activity of ethanol extracts from 6 plants
against oral candidal isolates. e latter were 65
Candida isolates collected from 175 patients attending
private dental clinics. e experimental plants, which
were purchased from local Saudi markets, included the
following: Zingiber officinale (ginger); Cinnamomum
(cinnamon); NS (black cumin); Syzygium aromaticum
(clove); Piper nigrum (black pepper), and chamomile.
It has been found that the highest inhibitory effects
were reached with a 100 μg/ml concentration of
cinnamon (34.6 mm) and clove (31.5 mm), while the
same concentration of black cumin and chamomile
recorded the smallest inhibition zone.50 However, the
mean values of the inhibition zone of both the black
cumin and chamomile were not significantly different
from that of Amphotericin B.5 Another study,51 claimed
by the authors to be the first of its kind investigated
the in vitro antifungal properties of Amphotericin B,
ketoconazole, and TQ against Candida albicans (yeasts
and biofilm) in their nanoparticle forms in comparison
with their conventional forms. e results showed that
the nanosized drugs’ fo-rmulation increased the drug’s
efficacy 24 times against Candida albicans in both yeast
and biofilm forms. us, this finding represents a major
innovation in the medical field, as biofilm growth is
more protected from host defenses and has enhanced
resistance to antimicrobial agents.51
Oral cancer. Oral cancer is considered to be a
multistep disease of accumulated genetic and epigenetic
alterations in epithelial cells, which generally precedes
histological changes. ese changes accumulate
throughout malignant transformation from benign
to precancer lesions to the invasive cancer state.52,53
Oral cancer is ranked as the sixth most frequent
cancer worldwide. Unfortunately, the 5-year survival
for oral cancer has remained at 50% for a long time.
is occurrence is due to several factors, such as late
diagnosis, disease relapse, resistance to chemotherapy,
and metastasis.54,55 Premalignant lesions could be
subclinical conditions with normal mucosa or clinically
obvious lesions, such as leukoplakia, erythroplakia, and
submucous fibrosis. Studies showed that premalignant
lesions are reversible conditions, as epithelial tissues
retain normal mucosal morphology. is is true if
carcinogenic insults related to an unhealthy lifestyle
habits (such as, alcohol consumption and tobacco
smoking) were adjusted. However, changing unhealthy
habits might be hard for some, or undesirable for
others. Instead, using pharmacological or natural
products to prevent the progression of premalignant to
cancerous lesions is a very attractive approach known
as chemoprevention.54,56-58 Studies revealed that TQ
restrains proliferation and promotes apoptosis in human
cancer cell lines.59-61
In addition, TQ can be used as a chemosensitizing
agent with drugs, or can be used with other
chemotherapy drugs to achieve a synergistic effect. An
example of this co-treatment is the combination of TQ
and cisplatin, which was found to have a synergistic
effect in preventing the proliferation and invasion of
human lung cancer.62 Here, we focus on the effect of
TQ in oral cancer treatment and prevention. Although
only a few studies have been performed on the effect
of TQ on oral cancer, it is still promising.60,63,64 A
study by Chu et al60 revealed that the treatment of
human oral cancer with TQ induces cell death by the
2 distinct mechanisms of apoptosis and autophagy.
Apoptosis is programmed cell death. It is regulated by
either the receptor-mediated death pathway, or by the
mitochondrial pathway. Apoptosis causes changes to the
cell that are characterized by cell shrinkage, bulge of the
membrane, breakage of DNA, and caspase activation.65
Autophagy is an important physiological process that
sustains cellular homeostasis under stress conditions.
In cancer therapy studies, autophagy-inducing agents
are used to stimulate nonapoptotic cell death.66
Experiments were performed in vitro and in vivo,
which strongly supported the TQ’s antitumor activity.
In vitro, treating SASVO3 oral cancer cells with TQ
inhibited the growth of cells. ese cells were arrested
at the sub G1 phase (apoptotic cell population). Protein
expression by western blots of Bcl2 (an inhibitor of
apoptosis) and Bid were decreased in a dose-dependent
fashion.
On the contrary, the protein expression of Bax (a
promoter of apoptosis) and cleaved caspase 9 were also
increased in a dose-dependent fashion. To verify the
activation of apoptosis through caspase 9, the authors
incubated SASVO3 cells with TQ and the caspase
9 inhibitor. Staining with annexinV/PI revealed a
decrease in the TQ-induced apoptotic population
after treatment with the inhibitors. Taken together,
TQ induced apoptosis through the initiation of
caspase 9. Autophagy-related proteins Beclim 1, class
III PI3K complex, Rubicon, and Atg family proteins
were expressed in SASVO3 cells treated with TQ.
Additionally, as a protein indicator of autophagy,
LC3II increased after TQ treatment and TQ induced
autophagy. In vivo, nude mice were injected with
241
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N. sativa and thymoquinone in oral health ... Al-Attas et al
luciferase expressing SASVO3 cells. Mice were
treated with either TQ or olive oil (control). e TQ
treatment reduced tumor weight by 3.4-fold by the
20th day. Protein expression of the TQ-treated tumor
showed high levels of Bax and LC3II compared with
the control animals. ese results supported the in
vitro results, where TQ treatment prompted apoptosis
and autophagy in vivo. is study verified the need
of multiple target therapy as an effective approach in
anticancer treatment.60 Abdelfadil et al64 carried out a
study on the treatment of oral cancer cells with TQ.
eir results showed that TQ induced apoptosis. e
mouse cell line used in that study represents chemically
induced oral squamous cell carcinoma (T28). Treating
T28 with TQ induced apoptosis through the blocking
of the p38β MAPK pathway and increased expression of
proapoptotic proteins Bid and Bad with the activation
of p53. Apoptosis in T28 cells occurred through caspase
3 cleavage. e difference in the apoptosis pathway
between this study and the previous one is probably due
to the use of different cell lines (human versus animal).
Interestingly, TQ treatment induced downregulation of
COX2, which in turn, decreases cell survival. Abdelfadil
et al64 stated that TQ has a promising potential in
anticancer therapy by promoting apoptosis and reducing
cell survival. e TQ not only can be used as a treatment
for cancer but also as a chemopreventive. It prevents
premalignant lesions to progress to cancer. Many studies
have illustrated this concept regarding TQ in different
cancer types.67,68 Only one oral cancer prevention study
through the use of TQ has been published.63 ey used
7,12 dimethyl benz (a) anthracene (DMBA) in an
induced hamster buccal pouch carcinogenesis model
to study TQ chemoprevention. e DMBA is known
to induce multistep carcinogenesis. It starts with a
sequence of hyperplasia, dysplasia and carcinoma,
which is very similar to the development of oral cancer.
For animals treated with TQ, the incidence of oral
neoplasm and cytokeratin expression was significantly
prevented.63 e NSE can be used in combination
with chemotherapeutics, such as cisplatin, to enhance
the anticancer activity of the drug and as a protective
agent for organs from its cytotoxic effect. We verified
the protective effect of NSE in a DMBA-induced
hamster buccal pouch carcinogenesis model treated
with cisplatin.69 e NSE protected the hamster kidney
from nephrotoxic effects. Kidney function tests showed
lower values in hamsters treated with TQ and cisplatin
than hamsters treated with cisplatin alone. In addition,
as found in this study, liver functions were better in the
NSE-treated groups. In summary, NSE, and particularly
TQ are promising products in the prevention and
treatment of oral cancer.
Conclusion and recommendations. e few last
decades have shown a rise in using herbal medicine
investigations to replace conventional treatments for
Table 2 - e effects of Nigella sativa (NS) extracts and thymoquinone (TQ) in dental caries and periodontal diseases.
Disease type Experimental model Treatment effects Reference
Dental caries (cariogenic bacteria)
In vivo Rats were challenged with Streptococcus mutans (S.
mutans) and fed a diet rich in sucrose
Lowered the caries score and plaque index 13
In vitro e antibacterial activity of NS essential oil and TQ
were screened against 30 human cariogenic strains using
the agar disk diffusion assay and minimum inhibitory
concentration (MIC) determination
NS essential oil showed more antimicrobial activity than
the pure TQ, NS essential oil has strong activity against
Streptococcus mitis (S. mitis), S. mutans, (MIC 2.13 mg/
ml),TQ showed a most important antibacterial activity
against S. constellatus (MIC 4 μg/ml)
18
In vitro Inhibition of teeth adherence was tested, as well as the
antibacterial activity using agar diffusion test followed by
minimum bactericidal concentration (MBC)
e black seed oil was effective in inhibiting the
adherence of S. mutans to the tooth surface at 10%
concentration. e black seed oil ethanolic extract has
10% MBC against S. mutans
1
In vitro e antibacterial activity was tested with the microwell
dilution method (the Kirby-Bauer method)
e results demonstrated the methanolic extract had
a higher zone of inhibition than either extract of NS
against S. mutans, S. mitis
24
Periodontal and gingival diseases
In vivo Rats were challenged with S. mutans and fed a diet rich
in sucrose
TQ had significantly lowered periodontal indices and
subgingival bacterial count in comparison with both the
negative and positive control groups
13
In vivo Rat periodontitis model. e gingival margins of the
rat’s molars were ligated with a 4/0 silk suture to induce
periodontitis
e oral administration of TQ helped in periodontal
disease prevention as it diminishes alveolar bone
resorption
32
In vivo Clinical randomized single-blind split mouth trial
(human)
e results showed significant gains in the clinical
attachment in the TQ groups compared with other
groups
26
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N. sativa and thymoquinone in oral health ... Al-Attas et al
Saudi Med J 2016; Vol. 37 (3) www.smj.org.sa
various diseases and conditions.42 Oral and dental
diseases have not been an exception. e literature
reported several primary studies1,13,18,24,26,32,33,36,39,40 that
investigated the role of NS and its active constituent
TQ in different areas of dentistry. Interestingly, the
results were positive and promising (Tables 2 & 3). e
NS and TQ demonstrated several potential therapeutic
effects on different oral and dental diseases. e NS and
TQ possess antiplaque activity, thus, they can help in
preventing both caries and periodontal diseases. Several
studies assessed the sensitivity of oral pathogens against
NS extracts and/or TQ, and the results were equivalent
to, synergistic with, or even better than the regularly
used antibiotics, such as amoxicillin or tetracycline.22,25
In addition, the seed extracts have anticandidal
activity, as well as wound and bone healing promoting
activities.42,51 Such results are encouraging for the
incorporation of these plants in dental therapeutics and
hygiene products. However, there were few studies, and
they were mainly conducted on animals. erefore,
more clinically controlled trials on humans are needed,
especially because the plant has no toxicity or health
hazards that have been reported by any researchers
who have been working on related clinical trials for
years.7,70 ere are still several plant properties that
are not well studied in relation to dental health or
diseases, including the anti-inflammatory and analgesic
effects.4,71 is could furnish the basis for a good
natural analgesic for toothache treatment. Additionally,
the immunomodulatory activity,72,73 makes the seed a
good alternative for oral immune diseases, as well as its
antioxidant and its antineoplastic activities, which have
been extensively studied in relation to several cancers,
including oral cancer.3,53-68 Moreover, further detailed
preclinical and clinical studies are required at the cellular
and molecular levels to investigate the mechanisms
of action of NS and its constituents, particularly TQ.
Overall, the studies that investigated the role of NS and
its active component TQ are preliminary, but the results
revealed that the plant has a potential therapeutic effect
for oral and dental diseases.
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... In Islamic belief, it is considered to be a cure for all diseases except death. NS has many pharmacologically active compounds; one of the most reported is thymoquinone having antioxidant, anti-inflammatory, and anti-microbial activity [22]. Thymoquinone has been extensively studied and is known to exert several therapeutic pharmacological effects, such as regulating blood lipid levels and blood sugar levels and controlling tumor growth and having protective effects on multiple body organs [23]. ...
... Thymoquinone has been extensively studied and is known to exert several therapeutic pharmacological effects, such as regulating blood lipid levels and blood sugar levels and controlling tumor growth and having protective effects on multiple body organs [23]. In addition, NS and thymoquinone are known to be beneficial in treating oral conditions, thus promoting oral health [22]. NS was effective against multiple antibiotic-resistant bacteria, including S. aureus, Pseudomonas aeruginosa and the fungus Candida albicans [24]. ...
... Although CHX has strong clinical and microbiological effects, it is reported to have many undesirable side effects [20]. On the other hand, NS may be a safer natural candidate for maintaining oral health, fostered by its antimicrobial and anti-inflammatory effects [22]. ...
... Bovine bone graft is needed to induce osteogenic activity to accelerate bone formation [6] Natural ingredient, one of which is Nigella sativa is known for its extensive medical from its main active component, thymoquinone. Thymoquinone is known to have remarkable properties, including anti-inflammatory, antioxidant, analgesic, anticancer, and antibacterial [11] [12,13]. The properties of Nigella sativa and active component can be combined with bovine bone graft in hopes to improving the process of bone formation. ...
... The increase of osteoblast leads to increased amount of osteoprotegerin (OPG) which control the differentiation of monocytes by binding to the ligand of the RANKL to compete with RANK [7]. Nigella sativa also demonstrate bone resorption reduction by inhibiting osteoclast production through its component, mainly thymoquinone, to reduce inflammation [11,12,14]. Bone resorption also further reduced by BBG through BMP function that reduce osteoclast [21]. ...
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Background:. Poor healing of alveolar bone after traumatic tooth extraction procedure increases the difficulty of treatments, especially in the field of prosthodontic. Therefore, adequate socket preservation of alveolar bone is beneficial. Nigella sativa (NS) and bovine bone graft (BBG) is expected to reduce osteoclast and increase osteoblast as a marker of alveolar bone healing. Purpose: This study was aimed to observe the effect of NS combined with BBG on osteoclast and osteoblast count on post-extraction socket of alveolar bone. Methods: Lower incisors of fifty-six Cavia cobaya were extracted and divided into four groups. First group was control group, second group was given BBG, third group with NS, and fourth group with NS and BBG combination. Cavia cobaya was terminated on the 7th and 14th day for further analysis of alveolar socket bone. Histological examinations of osteoclast & osteoblast were measured with a 400x magnification light microscope. One-way ANOVA and Tukey HSD tests were performed to analyze the data statistically. Results: There was a significant difference in osteoclast and osteoblast count between the groups. Both lowest mean of osteoclast and highest mean of osteoblast was found in the NS-BBG combination group on 7th and 14th day. Conclusion: The combination of NS and BBG can effectively decrease osteoclast and increase osteoblast count on post-extraction socket of the alveolar bone.
... Evidence suggests that the most significant active ingredients in N. sativa include thymoquinone (TQ ), thymohydroquinone, dithymoquinone, p-cymene, carvacrol, 4-terpineol, t-anethol, sesquiterpene longifolene, −pinene, and thymol, among others. Carvone, nigellicine, nigellone, citrostradienol, Antioxidant Activity of Nigella sativa Essential Oil cycloeucalenol, gramisterol, lophenol, ostusifoliol, stigmastanol, β -amyrin, butyrospermol, and cycloartenol are the other chemical components [2,5] bitter principle, tannin, resin, reducing sugars, glycosidal saponin, hederagenin glycoside, esters of unsaturated fatty acids with C15 terpenoids, esters of dehydrostearic and linoleic acid, aliphatic alcohol, −unsaturated hydroxyl ketone, 3-O-[12-L-rhamnopyrasyl(12)-D-glucopyranosyl)-L-xylopyranosyl (12)] Stigma-5,22-dien-3-D-glucopyranoside, cycloart-23-methyl-7,20,22-triene-3, 25-diol, nigellidine-4-O-sulphite, 11-methoxy-16, 23-dihydroxy-28-methylolean-12-enoate, N. mines A1, A2, B1, and B2 in addition to A3, A4, and A5 [1,[6][7][8][9][10][11][12][13][14][15][16]. The chemical structures of some important chemical moieties are shown in Figure 1. ...
... It has been demonstrated that N. sativa oil has potential against leishmaniasis, miracidia, cercariae, and Schistosoma mansoni. In the latter instance, co-treatment with praziquantel, a well-known anti-schistosomal and anthelmintic medicine for domestic animals, resulted in a potentiating effect from the oil of the black seed, which demonstrated high efficacy [13][14][15][16]. According to Simalango [22], ethanol extract of N. sativa (0.5-8%) exhibited anti-Ascaris suum action that was noticeably active. ...
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Nigella sativa oils have anti-inflammatory, antibacterial, antifungal, antiparasitic and antiprotozoal, antiviral, cytotoxic, anticancer, neuro-, gastro-, cardio-, and hepatoprotective properties, making them potential treatments for a wide range of illnesses. N. sativa oil also suggests positive benefits on the immunological, respiratory, and reproductive systems in addition to diabetes mellitus (DM), fertility, breast cancer, dyspepsia, osmotic balance, and other conditions. Thymoquinone (TQ) is a suitable target for its potential antibacterial, antimicrobial, anti-inflammatory, chemopreventive, antitumoral, and other actions among the various isolated chemical moieties. The N. sativa oil has been shown in various non-clinical and clinical investigations to benefit health. On the other hand, TQ in several animal experiments is clear to generate no adverse modifications of the body biomarkers; rather, it enhanced health quality. This study presents a more mechanistic review of the constitutions and oil of N. sativa. In conclusion, research on Nigella oil may represent a health breakthrough.
... Common names of Nigella sativa is black cumin, kalonji, Black caraway, Roman coriander, fennel flower, and Habbatus sawda etc. N. sativa is the member of Ranunculacea Family (AlAttas et al., 2016). Its plant has a shiny tripartite leaves and slight hairy stem (Srinivasan, 2018). ...
... Nigellone from N. sativa showed antiasthmatic activity by inhibiting the histamine release from the mast cells (Mathur, 2011). In an animal model of allergic asthma, alpha-hederin of N.sativa improved tracheal responsiveness and had considerable anti-inflammatory effect by lowering histamine and leukotriene production while boosting PGE2 from mast cells and perfused lungs (Akram Khan and Afzal, 2016;AlAttas et al., 2016;Ikhsan et al., 2018). In asthma, leukotrienes may act as inflammatory mediators. ...
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COVID-19 is a pulmonary disease caused by SARS-CoV-2. More than 200 million individuals are infected by this globally. Pyrexia, coughing, shortness of breath, headaches, diarrhoea, sore throats, and body aches are among the typical symptoms of COVID-19. The virus enters into the host body by interacting with the ACE2 receptor. Despite many SARS-CoV-2 vaccines manufactured by distinct strategies but any evidence-based particular medication to combat COVID-19 is not available yet. However, further research is required to determine the safety and effectiveness profile of the present therapeutic approaches. In this study, we provide a summary of Traditional Arabic or Islamic medicinal (TAIM) plants' historical use and their present role as adjuvant therapy for COVID-19. Herein, six medicinal plants Aloe barbadensis Miller, Olea europaea, Trigonella foenum-graecum, Nigella sativa, Cassia angustifolia, and Ficus carica have been studied based upon their pharmacological activities against viral infections. These plants include phytochemicals that have antiviral, immunomodulatory, antiasthmatic, antipyretic, and antitussive properties. These bioactive substances could be employed to control symptoms and enhance the development of a possible COVID-19 medicinal synthesis. To determine whether or if these TAIMs may be used as adjuvant therapy and are appropriate, a detailed evaluation is advised.
... Plant-based or natural goods are in high demand in developing countries, particularly in big cities, for their families' healthcare and home remedies for patients since they are safer. Furthermore, the World Health Organization (WHO) has urged underdeveloped countries to exploit medicinal plants as a natural resource because of their potential health benefits for humans (Alattas et al., 2016). Due to its positive impact on human health after years of research and experimentation on many types of plants, plant-based products such as roots, stems, leaves, flowers and seeds have emerged as a source of natural products and phytochemicals. ...
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Dental caries is a prevalent oral disease caused by Streptococcus mutans is one of the most common grampositive cocci and this is involved in formation of bacterial biofilm on the tooth surface. S. mutans is a major etiological agent in dental caries. The use of natural products can be alternative to antibiotics. Natural products has gained more popularity in recent years. In this study, antibacterial activities of combination of extracts of Salvadora persica L. (SP) and Zingiber officinale Rosc. (ZO) against S. mutans (SM) were performed, Along with GC-MS, analysis on individual methanolic extracts and combination of extracts of Miswak and Ginger. The antibacterial activities of combination of extracts were examined using the agar-well diffusion method and the inhibition zones were measured. The results demonstrated that the combination of extracts of S. persica and Z. officinale have significant antibacterial susceptibility against S. mutans, with inhibition zones ranging from 13.0 mm to 14.0 mm, depending on the concentration (solute percentage) of the extract. The minimum concentration (solute percentage) needed for ZO methanolic extract to inhibit the growth of SM were found to be 300 µg/ml and for SP and combination ZO + SP were found to be 5 mg/ml and 75 µg combined with 1.25 mg/ml, respectively. GC-MS analysis identified several bioactive compounds that may contribute to the observed antibacterial susceptibility. These results suggest that these natural products may have potential as an alternative to antibiotics for controlling oral-infections. Need further studies on different plants combination on different types solvent for their efficacy, mechanism of action of extracts. So in future, they can be used directly or products as a treatment for oral infections.
... This plant is traditionally used worldwide for culinary and medicinal purposes [15,16]. N. Sativa has been shown to have numerous properties, including immune-stimulatory, anti-inflammatory, hypoglycemic, antihypertensive, antimicrobial, antiparasitic, antioxidant, and anticancer actions [17][18][19][20]. N. sativa and its constituents have been traditionally used to relieve respiratory disorders such as asthma, bronchospasm, and chest congestion, although the precise mechanisms of action have not been elucidated [21]. ...
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Background: many previous studies have demonstrated the therapeutic potential of N. sativa total oil fractions, neutral lipids (NLs), glycolipids (GLs), phospholipids (PLs), and unsaponifiable (IS) in asthma patients. We therefore tested its effect on airway smooth muscle (ASM) cells by observing its ability to regulate the production of glucocorticoid (GC)-insensitive chemokines in cells treated with TNF-α/IFN-γ, and its antioxidative and reactive oxygen species (ROS) scavenging properties. Materials and methods: the cytotoxicity of N. sativa oil fractions was assessed using an MTT assay. ASM cells were treated with TNF-α/IFN-γ for 24 h in the presence of different concentrations of N. sativa oil fractions. An ELISA assay was used to determine the effect of N. sativa oil fractions on chemokine production (CCL5, CXCL-10, and CXCL-8). The scavenging effect of N. sativa oil fractions was evaluated on three reactive oxygen species (ROS), O2•-, OH•, and H2O2. Results: our results show that different N. sativa oil fractions used at 25 and 50 µg/mL did not affect cell viability. All fractions of N. sativa oil inhibited chemokines in a concentration-dependent manner. Interestingly, the total oil fraction showed the most significant effect of chemokine inhibition, and had the highest percentage of ROS scavenging effect. Conclusion: these results suggest that N. sativa oil modulates the proinflammatory actions of human ASM cells by inhibiting the production of GC-insensitive chemokines.
... In general, the studies conducted on NS and TQ in relation to dentistry are preliminary and limited, and most of them were conducted on experimental animals. However, the results showed that the plant has promising therapeutic properties that may be useful for oral and dental diseases [15]. Based on the previous data, we decided to conduct a study to evaluate the efficacy of Nigella Sativa oil on soft tissue healing and inflammation reduction compared to Eugenol in the Context of Dry Socket. ...
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Research background Dry socket is one of the most common complications occurring after the extraction of a permanent tooth, but despite its high incidence, there is no established treatment for this condition. Nigella sativa oil has anti-inflammatory properties and enhances wound healing. Thus, we have decided to conduct a study to evaluate the efficacy of Nigella sativa oil in the context of dry sockets. Aim of the study This study aims to evaluate the effect of a Nigella Sativa oil dressing compared with an Eugenol dressing for the treatment of dry sockets in terms of accelerating soft tissue healing and reducing the intensity of inflammation. Materials and methods A total of 36 patients (19 males, 17 females), ranging between 20 and 50 years, 40 sockets with Alveolar osteitis randomized into 20 sockets for each group. In the first group, Eugenol with a Gelfoam carrier was used, in the second group, Nigella Sativa oil with a Gelfoam carrier was used and after copious irrigation with normal saline in both groups. Soft tissue healing and the degree of inflammation were monitored on the third (T1) and seventh (T2) days. Results The results of our study showed clinical and statistical superiority in favor of the Nigella Sativa oil group compared to the Eugenol group at time T2, where the P-value was less than 0.05. Conclusions Within the limits of our study, we found that Nigella Sativa oil led to better healing of soft tissues and reduced the intensity of inflammation in the context of dry socket, and was superior in effectiveness to Eugenol, and we recommend its use for the treatment of dry socket.
... BioTech 2023, 12,19 ...
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In this study, biocompatible electrospun nanofiber scaffolds were produced using poly(-caprolactone (PCL)/chitosan (CS) and Nigella sativa (NS) seed extract, and their potential for biomedical applications was investigated. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), total porosity measurements, and water contact angle measurements were used to evaluate the electrospun nanofibrous mats. Additionally, the antibacterial activities of Escherichia coli and Staphylococcus aureus were investigated, as well as cell cytotoxicity and antioxidant activity, using MTT and DPPH assays, respectively. The obtained PCL/CS/NS nanofiber mat was observed by SEM to have a homogeneous and bead-free morphology, with average diameters of 81.19 ± 4.38 nm. Contact angle measurements showed that the wettability of the electrospun PCL/Cs fiber mats decreased with the incorporation of NS when compared to the PCL/CS nanofiber mats. Efficient antibacterial activity against S. aureus and E. coli was displayed, and an in vitro cytotoxic assay demonstrated that the normal murine fibroblast cell line (L929 cells) remained viable after 24, 48, and 72 h following direct contact with the produced electrospun fiber mats. The results suggest that the PCL/CS/NS hydrophilic structure and the densely interconnected porous design are biocompatible materials, with the potential to treat and prevent microbial wound infections.
... j. It also stops gum bleeding [34]. k. ...
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Nigella sativa is also known as wild or shahi jeera and is mostly consumed as a flavoring spice in Indian and Meditarrian cooking. Besides it is also used in the preparation of ayurvedic medicine used for the treatment of gastrointestinal problems, vomiting, diabetes, dyspepsia, fever etc. This magical spice has many medicinal uses with no or less side effects. Its seeds possess antimicrobial, anti-inflammatory, anti-ageing and anti-spasmodic.
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Background: Seeds of Nigella sativa L., commonly known as black seed, have been used in traditional medicine. Streptococcus mutans and Streptococcus mitis are normal flora bacteria found in human oral cavity, which cause dental caries and bad breathe oder. This project considered as an explorer study for the inhibitory effect of Nigella Sativa L. seeds extract against S. mutans and S. mitis. Material and methods: Two different extracts of Nigella sativa L. has been evaluated in vitro against Streptococcus mutans & Streptococcus mitis, the antibacterial activity was determined by the agar well diffusion method. Results: The results showed the zone of inhibition was found 12.7mm and 10.4mm at a ethanol extract against Strept. mutans & Strept. mitis respectively,while the inhibition zone of ether extract was found 6.3mm and 5.1mm against Strept. mutans & Strept. mitis respectively. Conclusion: Methanol extract was more effective in comparison with the ether extracts. The highest inhibition zone was observed with ethanol fraction and it inhibited the growth of two careiogenic bacteria.
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Medicinal plants and its constituents used as therapeutics drugs in the health management since ancient time and large population of the world relies on traditional medicine for primary health treatment. However, medicinal plant has opened a new window of research in diseases prevention and treatment due to safe, affordable and easy to access properties. In this vista, Nigella sativa (NS) are commonly used as traditional medicines worldwide in the disease prevention due to less side-effect and affordable properties. NS and its constituents are a rich source of antioxidant, an influential free radical scavenger and also modulator of various biological activities. In this review, we summarized the therapeutics effects of black seed and its constituents in the diseases treatment and prevention through modulation of antioxidant, anti-inflammatory, anti-tumor, hepato-protective and other genetic activities.
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Six ethanolic extracts from plants of Ginger (Zingiber officinale), Cinnamon (Cinnamomum verum), Black Cumin (Nigella sativa), Clove (Syzygium aromaticum), Black Pepper (Piper nigrum), and Chamomile (Anthemis nobilis) were purchased from local market in H'ail province, Saudi Arabia were assayed for the in vitro inhibitory activity against some oral Candidal isolates. The prevalence of oral candidal infections among poor control diabetes patients was higher (56%) than fair control (30%) and good control (7%) diabetes patients. Statistically, our data indicated that a higher significant difference between the prevalence of oral candidiasis and diabetic control (p-value = 0.001). Cinnamon and Clove plant extracts were the most effective of all pathogenic yeasts studied. Candida albicans, C. parapsilosis and C tropicalis showed greatest degree of sensitivity to Cinnamon and Clove plant extracts. The inhibition zone diameter recorded 34.6, 31.5; 45, 31; 45.5, 29.5 mm, respectively at 100 µg/ml concentration. Based on paired t-test, there is no significant difference between the mean values of the inhibition zone size of Amphotericin B, Black cumin, Chamomile and plant extracts were reported (P-value ˂ 0.05). Both Cinnamon and Clove extracts showed remarkable effect on C. albicans and C. tropicalis at very low concentration MIC, 15, 18 and 15, 19 μl/ml, respectively. [Mohamed A. Fareid. In Vitro: Evaluation of Inhibitory Activity of Some Plant Extracts Against Oral Candidiasis. N Y Sci J 2014;7(12):66-76]. (ISSN: 1554-0200). http://www.sciencepub.net/newyork. 9