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Antibacterial activity of ginger extracts and its essential oil on some of pathogenic bacteria

Baghdad Science Journal Vol.7(3)2010
Antibacterial activity of ginger extracts and its essential oil
on some of pathogenic bacteria
Mohammed Ibraheem Nader* Kais Kassim Ghanima*
Safaa Abdalrasool Ali* Dalia Ahmad Azhar**
Received 1, May, 2009
Acceptance 7, September, 2009
The antimicrobial activity of ginger extracts ( cold-water, hot-water, ethanolic
and essential oil ) against some of pathogenic bacteria ( Escherichia coli , Salmonella
sp , Klebsiella sp , Serratia marcescens, Vibrio cholerae , Staphylococcus aureus ,
Streptococcus sp) was investigated using Disc diffusion method , and the results were
compared with the antimicrobial activity of 12 antibiotics on the same bacteria .
The results showed that the ginger extracts were more effective on gram-positive
bacteria than gram-negative . V. cholerae and S. marcescens,were the most resistant
bacteria to the extracts used , while highest inhibition was noticed against
Streptococcus sp (28 mm) . The ethanolic extract showed the broadest antibacterial
activity ( 11 to 28 mm ) , in comparison with moderate activity of essential oil , it was
observed that the cold-water extract was more effective on the bacteria than hot-water
extract .
Ginger ethanolic extract presented higher diameter of inhibition zone for
Streptococcus sp than in Ciprofloxacin , Cefotaxime , Cefalotin , Cephalexin and
Cephaloridine , also it was found a similarity between the higher inhibition zones of
ethanolic extract of ginger and some antibiotics for S. aureus , E. coli , Salmonella sp
and Klebsiella sp . V. cholerae and S. marcescens,also highly resistant to antibiotics .
Phytochemical analysis of ethanolic extract of ginger revealed the present of
glycosides, terpenoids, flavonids and phenolic compounds
Keywords: Antibacterial activity, ginger extracts.
Introduction :
Ginger (Zingiber officinale) is
member of the zingiberaceae family of
plant that include cardamom and
turmeric. The strong aroma of ginger is
the result of pungent ketones
including gingerol [1].The medicinal
use of ginger rhizome dates 2,500
years in china and India, where it was
prescribed to treat headaches, nausea,
rheumatism and colds [2].Ginger has
been shown to have antimicrobial
activity against pathogenic bacteria
such as Escherichia coli, Proteus sp.,
staphylococci, streptococci and
Salmonella [3,4] .The ginger has the
capacity to eliminate harmful bacteria
responsible for most of the diarrhoea,
especially in children . It has been
shown to reduce the stickiness of blood
platelets, hence may help reduce risk
of arthrosclerosis[5], antimicrobial
activity of spices and herbs has been
known and described for several
centuries. At present, its estimated that
about 80% at world population rely on
botanical properties of medicines to
meet their health need . Herbs and
spices are generally considered safe
and proved to be effective against
certain ailments [6].
*Institute of Genetic Engineering and Biotechnology for Post Graduate Studies, University of
**Collage of Science, University of Baghdad
Baghdad Science Journal Vol.7(3)2010
Since the introduction of antibiotics
there has been tremendous increase in
the resistance of diverse bacterial
pathogenes [7]. The enterococci have
intrinsic resistance to multiple
antimicrobials, most drug resistance in
enteric bacteria is attributed to the
wide spread transmission of resistance
plasmid among different genera [8]In
the present study we have evaluated
the antibacterial effect of the extracts
of ginger against some of pathogenic
bacteria. The inhibitory effect of
ginger was compared with the effect of
12 antibiotics and the results are
discussed and also find out the
phytochemical active constituents.
Materials and Methods:
The bacterial isolates
E.coli,Salmonella sp, klebsiella sp, S.
marcescens, and V. choierae were
isolated from gastrointestinal
infections, also S. aureus and
Streptococcus sp were isolated from
respiratory tract infections. All the
bacteria were obtained, as clinical
isolated, from Al-Yarmook teaching
hospital in Baghdad. Bacterial cultures
were maintained on Nutrient
agar(NA)Slopes. They were
subcultured monthly and subsequently
stored at 4oC.
Culture preparation
Aloopfull of 24 hr. surface growth on a
NA slope of each bacterial isolate was
transferred individually to 5ml of Brain
heart infusion broth(PH 7.6)and
incubated at 37oC for 24 hr, bacterial
cells were collected by centrifugation
at 3000rpm for 15 min., washed twice
and resuspended in 0.1% pepton water.
Turbidity was adjusted to match that of
as Mcfarland standared (108 CFU/ml).
Then 1:10 dilution of the cell
suspension was performed to give an
inoculum concentration of 107CFU
Ginger extraction
The ginger rhizomes were washed with
clean sterile distilled water and
allowed to air-dry for one hour , then
the outer covering of the ginger were
manually peeled off and the ginger was
washed again and extracted using the
following procedures:
A-cold-water extraction
Exactly 20g of fresh ginger rhizomes
were blended into fine powder and
soaked in 100ml of distilled water for
24 hr .The pulp obtained was left in
aclean ,sterile glass container and
shaken at 150 rpm for 8 hr vigorously
to allow for proper extraction and it
was filtered using asterile muslin cloth
after which the extract was obtained,
air-dried and stored below ambient
temperature until required[9]
B-Hot-water extraction
Exactly 20g of fresh ginger rhizomes
were blended and soaked in 100 ml of
hot water at 80 C (shaker water bath)
at 150 rpm for 24hr.,the resulted juice
was extracted air- dried and storied as
in above [9].
C-Crude ethanolic extraction.
20g of small pieces of fresh ginger
rhizomes were soaked in 100ml of
95% ethanol ,and shaken at 150rpm for
24 hr at ambient temperature .the
mixture then filtered. The filterates
were evaporated using vacuum rotary
evaporator,and frozen at -20oC .Stock
solutions of crude ethanolic extracts
were prepared by diluting the dried
extracts with 10% dimethyl sulphoxide
D-Essential oils
300g of small pieces of fresh ginger
rhizomes with distilled water (1L)
were placed in flask (2L) together
after steam distillation, the essential
oils were collected, dispensed into dark
bottles, and stored at 4° C until used
Baghdad Science Journal Vol.7(3)2010
Antibacterial screening test of
extracts using disk diffusion method.
The disk diffusion test was performed
using standard procedure by Jorgensen
et al. [11].The inoculum suspension of
each bacterial isolate was swabbed on
the entire surface of Muller-Hinton
agar (MHA)(pH7.3).Sterile 6mm filter
paper discs (Watman No.3) were
aseptically placed on MHA surface,
and crude ethanolic extract, essential
oil , hot water extraction and cold
water extraction were immediately
added to discs in volume of 20 ml. A
20ml aliquot of 10% DMSO and
distilled water were also added to a
sterile paper discs as a negative
control, whereas an antibiotic
screening by disc method used as a
positive control.
The plates were left at ambient
temperature for 15 min. to allow
excess predifferent of extraction prior
to incubation at 37° C for 24 hr.
Diameters of inhibition zone were
measured each experimental was done
in duplicate.
Inhibition zone with diameter less
than 12mm were considered as having
no antibacterial activity ,diameter
between 12 and 16 mm were
considered moderately active, and
these with >16mm were considered
moderately active[12].
Antibiotic sensitivity testing
The test microorganisims were also
tested for their sensitivity by Disc-
diffusion method ( Kirby-Bauer
method ) [13] against the antibiotics
manufactured by Bioanalyse and
Oxoid in 2008 with the concentration
(µg/disc) , Penicillin G(10),
Ampicilin(10), Cefotaxime(30),
Cephalexin(30), Cefalotin(30),
Cephaloridine(30), Trimethoprime
Tetracyclin(30), Erthromycin(15),
Kanamycin(30), Vancomycin(30) and
Phytochemical anylysis
The identification tests were done to
find the presence of the active
chemical constituents such as
alkaloids, glycosides, terpenoids,
flavonids , phenolic compounds ,
reducing sugars and tannins by the
procedures as described by Siddiqui
and Ali (1997)[14]
Result and Discussion:
The results of antibacterial activity of
ginger extracts (cold-water, hot-water,
crude ethanolic and essential oil)on the
pathogenic bacterial isolates (E. coli,
Salmonella sp, klebsiella sp, S.
marcescens, V. cholera ,S. aureus and
Streptococcus sp) are shown in
Table (1): Antibacterial activity of
crude extracts of ginger against
some of pathogenic bacteria.*
Diameter of inhibition zone (mm)
cold -water
hot -water
cus aureus
s sp.
*Data are means of two replications. **
N.I.:No. Inhibition.
The results of this work indicates that
the ginger extracts were more effective
on gram positive bacteria (the widest
zone of inhibition was 28 mm) than on
gram negative bacteria (the widest
zone of inhibition was 20mm). This is
probably due to the differences in cell
wall structure of gram-positive bacteria
and gram negative bacteria. These
results agree with observations of
theAkoachere et al. [15], who had
reported that the extracts of ginger
exhibited antibacterial activity against
the pathogens S.aureus and
Baghdad Science Journal Vol.7(3)2010
Streptococcus pyogenes .Highest
inhibition was noticed against
Streptococcus (with highest inhibition
zone 28mm).
In gram negative bacteria it was
observed that ginger extracts(except
hot-water extract ) had activity on E.
coli , Salmonella sp and Klebsiella sp (
the range of inhibition zone was 12 to
20mm ) , while S.marcesces and
V.cholerae were the most resistant
bacteria to all extracts used . These
results are contradictory to the
observations of Indue et al.[12], who
had reported that the ginger extracts
did not show any antibacterial activity
against all serogroups of E.coli and
Salmonella sp.The differences may be
due to a difference in the variety of the
ginger used in this study , the
difference in the strains of pathogenic
bacteria and the source of samples .
The ethanolic extract of ginger
showed the broadest antibacterial
activity by inhibiting growth of all
bacterial isolate tested (the diameter of
inhibition zone,11-28mm).This credit
to ethanol extraction was supposed to
ethanol being an organic solvent and
will dissolve organic compounds
better, hence liberate the active
component such as zingerone, gingerol
and shogaol required for antimicrobial
activity [5]
It was observed that the cold water
extract of ginger was more effective on
the bacteria than hot-water extract, this
may be explained by the fact that the
antimicrobial substances in the ginger
extract are destroyed by heat from the
hot-water which might have raised the
temperature of the extracts inactivating
them[16].Nelson et al. [5] explain that
the antimicrobial substance in the
extract are mainly phenolic compounds
were destroyed or inactivated by heat .
Ginger essential oil possessed
moderate antibacterial activity in this
study. The major pungent compound
of ginger are gingerone and gingerol
which have strong inhibitory activity
against pathogenic bacteria [17].These
result disagree with observations of
Suree and Pana [18], who obtained that
the inhibitory activity of essential oil
was greater than that of ethanolic
extract . The greater effect of ethanolic
extract compared to the other may be
due to that plant extract in organic
solvents provided more cnsistent
antimicrobial activity , also we think
that the ginger oil has therapeutic
properties such as analgesic ,
antiemetic and antispasmodic more
than antibacterial properties .
The antimicrobial susceptibility results
for the pathogic bacterial isolates
against commonly used antibiotics are
summarized in table (2).
Table (2) antimicrobial susceptibility of some pathogenic bacteria to antibiotics.*
Penicillin G
*The results of sensitivity to antibiotics were performed in accordance with NCCLS guidelines (19).
R: Resistant
** The number is mean the inhibition zone in mm .(the bacteria intermediate sensitive or susceptible to
Baghdad Science Journal Vol.7(3)2010
The results showed that all isolates
were resistant to 3 or more
antibacterial and defined as multidrug
resistant. Ginger extract presented
higher diameter of inhibition zones for
Streptococcus sp than in Ciprofioxacin,
Cefotaxime, Cefalotin, Cephalexin,
and Cephaloridine.
It was found there is a similarity
between the higher inhibition zones of
ethanolic extract of ginger and some
antibiotics for S.aureus, E.coli,
Salmonella sp ,and Klebsiella sp, also
observed that V.cholerae and S.
marcescens highly resistant to
antibiotics as in their resistant to ginger
extracts and this had led to the
suggestion that there may be the
presence of multiple plasmids in the
mutants or plasmid carrying multiple
resistance determinants[20].Also as in
the effect of antibiotics it was
suggested that the antimicrobial action
of spices is due to the impairment of
variety of enzymes systems involving
in the production of energy or
synthesis of structural components in
microbial cells [21].
Phytochmical analysis of ethanolic
extract of ginger revealed the presence
of glycosides, terpenoids, flavonids
and phenolic compounds (table 3) . It
has been observed that there is a
possibility of synergism between the
active compounds in the crude extract
than in isolated constituents [22] .
Acetone and ethanol extracts of ginger
contains pungent substances namely
Oleoresin (gingerol and shagaol) ,
phenols(zingerone and gingeol ) and
paradol [23]. Hydroethanolic ginger
extract exhibited potent antibacterial
activity against gram positive and gram
negative bacteria, this effect may be
due to gingerols and phenolic
Table (3) chemical constituents of ethanolic extract of ginger.
The type
of extract
+ve=detected -ve=not detected
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Baghdad Science Journal Vol.7(3)2010
, Streptococcus sp, Staphylococcus aureus, Vibrio cholera, Klebsiella sp Serratia marcescens , Salmonella sp, Escherichia coli
                                                                                                             
 V. cholerae S. marcescens
Streptococcus sp
                                                                                       
Streptococcus sp
Ciprofloxacin Cefotaxime Cefalotin CephalexinCephaloridine
                                                                               S. aureus , E. coli , Salmonella sp  Klebsiella sp
V. cholerae S. marcescens
                                                                                                                 
... Later on, inhibition zones have been measured in millimeter. [12] All tests have been carried out in triplicate and their means have been recorded. ...
... The inhibition zones were measured in millimeter and were taken as a mean of three independent measurements. [12] The MIC value was taken as the least concentration of the methanol extract that shows a clear zone of inhibition, [14] antifungal activity was recorded when the inhibition zone was major than 6 mm. [13] Cutaneous Infection in Adult Mice (in vivo Study) ...
... Later on, inhibition zones were measured in millimeters. [15] All tests were carried out in triplicate and their means were recorded. ...
... The inhibition zones were measured in millimeter and were taken as a mean of three independent measurements. [15] The MIC value was taken as the least concentration of the methanol extract that shows a transparent zone of inhibition. [17] Antibacterial activity was recorded once the inhibition zone was major than 6 ml. ...
... The antimicrobial activity of active composite films was therefore tested against foodborne pathogenic bacteria E. coli (Gram-negative) and S. aureus (Gram-positive), and the results are presented in Table 5 Values are mean ± S.D. Means with different superscript letter within same column are significantly different (p>0.05) gram-negative; similar results were reported by Nader et al. (2010). ...
The present investigation reported the effect of incorporation of green tea extract (GTE) (1%), ginger essential oil (GEO) (1%) and nanofibrillated cellulose (NFC) (1, 2%) on the physicomechanical, barrier and antimicrobial properties of starch films. The reinforcement of NFC (2%) caused a significant (p<0.05) increase in tensile strength (47.6%) and decrease in water solubility (32%), wettability (21.4%) and water vapour permeability (18.4%) of starch films. The inclusion of natural extracts (GTE, GEO) yielded films with high antioxidant activity (50.5 µmolTE/g), and high inhibitory effect against Staphylococcus aureus (81%) and Escherichia coli bacteria (71%). The films showed colour change in alkaline media, suggesting their potential use for active packaging. The films also passed the biodegradability test; degrading in 14 days in vegetable compost. The optimized active films showed high effectiveness in keeping the quality and extending the shelf life of strawberries by 4 and 8 days at ambient and refrigeration storage respectively.
... The two important compounds include chymopapain and papain which helps in digestion 49 . The leaves have antimalarial and antiplasmodial activity and are also reported to treat dengue fever by potentially increasing the number of thrombocytes and leucocytes 50 Our results for the antimicrobial properties concur with studies that have a similar zone of inhibition for clove 56 jasmine 57 , eucalyptus 58 , ginger 59 , basil 60 , neem leaves 61 , citrus 62 and neem seed oil 63 . However, there are lack of studies that report the zone of inhibition using essential oils from garlic, guava, papaya and noni leaves. ...
Traditionally, crude extracts from various plants were used for treatment of diseases and ailments, while spices have been used for flavour, as preservatives, in rituals and as medicines for treating infectious diseases. The essential oils of 12 medicinal plants and spices were extracted and tested against Escherichia coli 0157:H7 (EHEC) to determine the antimicrobial properties. The selected plants and spices are Eugenia caryophyllata (F), Jasminium (F), Eucalyptus globulus (L), Zingiber officinale (R), Allium sativum (L), Occimum sanctum (L), Azadirachta indica (L), Psidium guajava (L), Citrus limon (L), Carica papaya (L), Morinda citrifolia (L) and Azadirachta indica (seed). These plants and spices were chosen due to their dependence by local households as a means of traditional medicine. Essential oils extracted from the plant and spices showed growth inhibition of E. coli 0157:H7, whereas the highest antimicrobial activity was recorded for clove oil. Jasmine, pawpaw and neem (seed oil) had the lowest growth respectively. All other extracts had moderate activity. Additionally, the aqueous and ethanol extracts of each plant were used to determine the total phenolic content (TPC). From the plants tested, the TPC of aqueous extract varied from 612±3.15 to 2.67±0.11 (mg GAE/100gdw), while TPC of ethanol extract varied from 434±2.87 to 1.02±0.09 (mg GAE/100gdw). The highest TPC was recorded for noni aqueous extract and the lowest was for jasmine ethanol extract. This study reports the inhibitory effects and phenolic content of 12 herbs and spices and thus its potential use for developing safe pharmaceutical agents.
... Ginger oil has been reported to be composed by α-curcumene, αzingiberene, β-bisabolene, β-sesquiphellandrene, cineole, 2,2-dimethyl-3-methylenenorbornane and rosefuran epoxide [8; 9]. Nader reported that extract ginger oil was contained by alkaloid, glicosides, terpenoid, flavonoid, phenolic [18]. Stoyanova [17] revealed that antimicrobial activity of the components in ginger oil was very weak on the Gram-negative and Gram-positive bacteria. ...
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The aim of the study was to evaluate antimicrobial activity of essential oil from local plants or plants cultivated in Indonesia against three food-borne pathogens, Salmonella Thypimurium, Bacillus cereus and Staphylococcus aureus. A total 6 essential oil extracted from ginger (Zingiber officinale), turmeric (Curcuma longa), candlenut (Aleurites moluccanus), lemongrass (Cymbopogon citratus), clove bud (Syzygium aromaticum), and galangal (Alpinia galanga). By using disc diffusion assay, the highest antimicrobial activity against S. Tyhimurium, B. cereus and S. aureus was shown by clove bud oil (3.67 ± 0.58 mm), lemongrass oil (3.58 ± 0.14 mm) and clove bud oil (5.25 ± 0.75 mm), respectively. By using Minimum Inhibitory Concentration (MIC), the concentration of essential oil to inhibit the growth of S. Tyhimurium, B. cereus and S. aureus was found on clove bud oil for 0.39 %, lemongrass oil for 1.56 % and clove bud oil for 0.78 %, respectively. Out of the essential oil tested, clove bud oil and lemongrass oil showed promising antibacterial activity against S. Thypimurium, B. cereus and S. aureus.
... DMSO well was used as a negative control and bacterial plates were incubated at 37 °C for 24 hrs. The diameters of inhibition zones were measured, later on (10) . ...
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It was found that Ginger extract have a good effect on bacterial isolates from patients with otitis media.
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The aim of this study was to evaluate the effect of aqueous extracts from different parts of plants such as berries of guelder rose (Viburnum opulus), seeds of cardamom (Elettaria cardamomum), musk (Myristica fragrans) and indian cumin (Cuminum cyminum), rootstock of ginger (Zingiber officinale) and liquorice (Glycyrrhiza glabra) on the quality of curd-type cheese. We produced organoleptically acceptable aqueous plant extracts (1.5% concentration) and evaluated their antimicrobial activity. According to the standard methodology we manufactured curd-type cheese. During the storage we identified physico-chemical properties (pH and colour coordinates), the number of lactic acid bacteria (LAB) and sensoryprofile properties of the final product. The experiment shows that plant extracts extended the shell-life of curd-type cheese, and the substances contained there act as natural preservatives. Curd-type cheese supplemented with plant extracts compared to the control sample is microbiologically safe. The study proves that curd-type cheese can be improved by adding plants rich in biological active substances, to improve the sensory properties, increase the biological value and extend the shell-life as safety by natural means. The effect of plant extracts has shown sensory properties of curd-type cheese – colour, taste, odour and acceptability.
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To investigate the antibacterial activity of Zingiber officinale (ginger) Garcinia kola (bitter kola) on four respiratory tract pathogens. A prospective study based on laboratory investigations. Department of Life Sciences, University of Buea. Throat swabs were collected from 333 individuals with running nostrils, cough and/or catarrh in three localities of Buea namely Bokwango, Molyko and Bolifamba. Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae and Haemophilus influenzae were isolated from the specimens using standard microbiological procedures. The antibacterial activity of ethanolic extracts of ginger and bitter kola, were investigated on these pathogens using the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays. The extracts exhibited antibacterial activity against the pathogens. The MIC of extracts ranged from 0.0003 microg/ml to 0.7 microg/ml for ginger and 0.00008 microg/ml, to 1.8 microg/mL for bitter kola, while MBC ranged from 0.1.35 microg/ml to 2.04 microg/ml for ginger and 0.135 microg/ml to 4.2 microg/ml for bitter kola. Results indicated that extracts of ginger root and bitter kola may contain compounds with therapeutic activity.
Phytochemical methods. Chapman and Hill. London 10-European Pharmacopoeia
  • J B Harborrne
Harborrne, J.B.1984. Phytochemical methods. Chapman and Hill. London 10-European Pharmacopoeia. 1975. vol.3, Maisonne uve SA, Sainte Ruffine, pp.68.
Medical microbiology 21 th
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Jawetz, M., Brooks. G. F.,Batel. J. S. and Morse. S. A. 1998. Medical microbiology 21 th.ed. Applton and Lange, California
Laboratory methods in antimicrobial chemotherapy
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