Original Research
ANTIFUNGAL
AND ANTIBACTERIAL ACTIVITY OF ALOE VERA
PLANT EXTRACT
DANISH P, ALI
Q, HAFEEZ MM, *MALIK A
Institute of
Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
Corresponding
author email: philemon.danish@gmail.com,
arifuaf@yahoo.com
(Received
4th January 2020; Accepted 24th March 2020)
Abstract: Aloe vera is a well-known medicinal plant used
in many therapeutic purposes. Naturally it is composed of many useful compounds
that have ability to use for treatment of many diseases. The active compounds
reported in this plant are saponins, sugar, enzymes, vitamins, aloesin,
aloeemodin, aloin, acemannan aloemannan, aloeride, methylchromones, flavonoids,
naftoquinones, sterols, minerals, anthraquinones, amino acids, lignin and
salicylic acid and other different compounds including fat-soluble and
water-soluble vitamins, enzymes, minerals, simple/complex sugars, organic acid
and phenolic compounds. In this study aloe vera is used for antibacterial and
antifulgal activity against different strains of bacteria and pathogenic fungal
strains. Ethanol extract of Aloe vera leaves and roots is applied on these
bacterial and fungal strains in different concentrations (15, 20, 25, 30µl). Bacillus
cereus, Bacillus subtitis, Bacillus megaterium, Streptococcus pyogenes,
Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter
baumannii, and some other bacterial strains are used for this study.
Escherichia coli and Agrobacterium tumefacins shows zone of inhibition around
18mm which consider as good result. Bacillus subtitis and Bacillus megaterium
also shows good result around 16mm. Proteus mirabilis and Pseudomonas
aeruginosa shows minimum zone of inhibition which is around 11mm. among all
used fungal strains (fuserium oxysporum, Candida albicans, Aspergillus
fumigatus, Aspergillus niger) fuserium oxysporum and Aspergillus niger shows
excellent results around 19mm both against root extract and leaves extract.
Keywords:
Aloe vera,
Bacterial strains, Fungal strains, Anti-bacterial, Anti-fungal
In
developing countries pathogenic microorganisms, fungus and bacterial strains
are the main cause of life-threatening infections which leads to mortality and
morbidity in immunocompromised patients (Al-Bari et al., 2006). Many antibiotics and antimicrobial agents are
available in market which can kill these microbes or inhibit the growth of
these microbes and involve in control of these pathogenic microorganisms. But
the problem is that, these microbes are becoming more resistant day by day
against these medicines even that many microbes are multidrug resistant. So treat of these disease causing and
multidrug resistant microbes with several antibiotics influence an enormous
threat on public health (Hajipour et al. 2012, Rojas et
al. 2006). With the kill of pathogens, these
medicines can also cause several side effects. So there is a need of natural,
safer and cheaper source of antifungal and antibacterial agents. So for control
of multidrug resistant microbes and safe use of medicines, people prefer to use
of natural sources as medicines. Plants are the alternative source of
antimicrobials that is safer, natural, cheaper and time tested source instead
of other antibiotics (Van der et
al.2001, Sharif et
al. 2006, Dilhuydy et
al. 2003). People know that many plants have a
great medicinal ability, and for a long time ago people use plants throughout
the globe for cure many infections. Since 2000BC plants are a great interest as
phytomedicines both in Eastern and Western world. Every progressive
civilization emphasizes the use of herbs. Ginseng is used by Chinese around
3000 years ago and to reduce the fever Americans use willow bark tea. As the
use of herbal extracts is consider pure, simple and safe so the popularity of
herbal products around the world may reflects the fact that many people do not
believe in medical practices with allopathics (Sharif et
al. 2006). The mostly used herbal compounds in
dental field are ginseng, ginger, clove and garlic (Dilhuydy et
al. 2003). Furthermore, in addition to the
techniques used for processing and packaging, the strength, quality and purity
of the drug is depend on the location, time and season of cultivation.
According to WHO 80% people still use herbal medicines. Many plants are used
for their medicinal ability worldwide. This study is focus on Aloe Vera plant. The word Aloe vera is derived from an Arabic word
“Alloeh” means that “shining bitter substance” and the ‘Vera’ is a Latin word
means “true”. Aloe vera is an herb that
is used for over 2000 years, and has a great ability to use in phytotherapy or
phytomedicines. It is cactus like plant that has around 360 species and grows
in hot dry climate, and now a days it have high demand that’s why it is cultivating
in large scale (Newall et al. 1996).
Egyptian scientist regarded Aloe vera
“the plant of immortality” and around 2000 years ago Greeks called it as
“universal panacea
It’s
an eminent medicinal plant belongs to a family liliaceae (Reynolds et al.1999, Kawai et al. 1993,). It’s almost found throughout the globe but it grows
best in hot tropical environments. It has
high water contents which is ranges from 99.0-99.5%. Because it has high
capacity for holding of water so it is use for keep moisturize the skin. and
any damaged on skin can be treated by its gel as its gel enhance the
restoration of wound and stimulate the cell growth, Stomach ailments,
constipation, thermal burn, sunburn, injuries caused by radiations, skin
disease, inflammatory effect, diabetes, ulcer etc. can be treat by the use of Aloe vera gel (Foster et al 1999). Now a days many juice products of Aloe vera are available
in market and it’s consider that many gastrointestinal problems can be treated
by A.vera juice, whenever mucus membrane of stomach got any damage or
irritation, in many regions A.vera juice
can be preferred to drink for the protection and healing of it (Eshun et al. 2004). Several researches also proposes that body’s
immune system can be stimulate by the gel of Aloe vera (Davis et al,.
1994)
It’s also used in many products such as
pharmaceutics, cosmatics and in food industry etc. (Klein
et al.1988).
Rather than 99.0-99.5% water the others 0.5-1.0% is testified to comprise over
200 active compounds and 75 nutrients. The active compounds reported in this
plant are saponins, sugar, enzymes, vitamins, aloesin,
aloeemodin, aloin, acemannan aloemannan, aloeride, methylchromones, flavonoids,
naftoquinones, sterols, minerals, anthraquinones, amino acids, lignin and
salicylic acid and other different compounds including fat-soluble and
water-soluble vitamins, enzymes, minerals, simple/complex sugars, organic acid
and phenolic compounds (Radha et al,
2014). A. vera gel have high
moleculer weight compounds which demonste benificial effect. Lactine like
proteins (Bajwa et al., 2007),
polysacchrides (Subramanian et al., 2006) and postagladins (Guillette et
al,. 1991), Manos-6-phosphate shows a role in the healing of wound (Davis et al,. 1994), bradykinin-degrading
glycoproteins may shows anti inflamatory effect (Yagi et al., 2002). For antiviral properties anthraquinones have been
studied from various plants (Sydiskis et
al., 1991).
The plant consists of two parts outer covering
and a parenchyma aloe gel which is almost colorless and present inside the
outer covering. Based on in vivo and in vitro study both these two parts shows
medicinal properties. Total extract of the plant shows antibacterial,
antifungal, anti-inflammatory and anti-arthritic properties (Newall et al. 1996, Kumar et al. 2015). The Aloe vera extract have been developed,
particularly sensitive to a variety of bacteria, Gram-negative pathogen,
Gram-positive pathogens and some fungal pathogens. Inhibition Insulation
compounds have clearly demonstrated their usefulness to various pathogenic
microorganisms. It is elucidated that the application of plants in traditional
medicine in the treatment of various diseases caused by these pathogenic
strains. Plants used in conventional medicine, as well as plants used in the
treatment of various diseases of these pathogenic strains. In addition,
identification of these antimicrobial compounds enhances their growth by
studying the structure/activity of new antimicrobia. In this present study we observed the
antibacterial and antifungal activity of ethanol extract of root and leaf of Aloe vera.
Material and methods
Sample
collection
Aloe vera is a medicinal plant which have
an ability to do activity against many microbes. It is stem less plant and ts
height ranges from 60-100cm. It have green to grey-green colored thick and
fleshy leaves. But some verities show white flacks on their stem. Polymannans,
acetylated mannans, anthrones and anthraquinone C-glycosides etc are the
phytochemicals found in Aloe vera. The
anthraquinones, such as emodin and various lectins are also found in it. This
study is done in The University of Lahore, Pakistan. For this study plant
sample is collect from three different localities (canal, pound and growing
fields) of local area of chak N0.377/E.B, Burewala, Pakistan. After collect the plant, its washed under tap
water to remove any dust particles and other insect larvae. After washing
thoroughly, we did weight of whole plant by the use of electronic weight
balance in plant tissue culture lab in the University of Lahore. Than separate
the roots and shoot and weight the shoot and roots separately. After complete
the weighing we cut the plant leaves into small pieces with the help of
sterilized knife and put these pieces into sterilized jars and filled these jars
with 99.5% ethanol and kept it for three days and stirred occasionally as shown
in fig.1. After that we strained the sample with help of sterilized strainer.
Than we process the strained sample in Colum chromatography (use silica gel) in
plant tissue culture lab. After the Colum chromatography we use rotary evaporator
for extraction to making final ethanol extract of Aloe vera, shown in fig.2, in pharmacy lab in university of the
Lahore. Extraction of plant roots were also done with the same method. Now it’s
ready for check its activity against any microbe.
Preparation of
the assay
We
used the Kirby-Bauer (disc diffusion) method with some modifications and used
the crude ethanol extract. The plant is cut into pieces, make ethanol extract
of plant. And then prepare this sample with different concentrations of ethanol
extract which are 15, 20, 25 and 30 µg respectively and kept it for 3 days and
stirred occasionally. Microbial growth was subjected to these samples for 24
hours. Also prepared root sample for assay. Prepare ethanol extract of roots
and prepared this root sample with different concentrations of ethanol extract
which are 15, 20, 25 and 30 µg respectively and kept it for 3 days and
stirred occasionally. Microbial growth is checked on these samples for 24 hours
Inoculum
preparation
Stock
cultures of bacteria and as well as fungus were prepared in microbiology lab.
Prepared stock culture of gram negative bacteria Escherichia coli, Acinetobacter baumannii, Pseudomonas aerugenosa,
Salmonella typhii, Agrobacterium tumefacins, Proteus mirabilis, Proteus
vulgaris and gram positive bacteria
bacillus cereus, bacillus subtitis, bacillus megaterium, streptococcus
pyogenes, staphylococcus aureus, enterococcus faecalis and for fungal
activity, prepared culture of fuserium
oxysporum,
Candida albicans, Aspergillus fumigatus, and Aspergillus niger. These Microbial
cultures were stored on nutrient agar media, and store it at 4°C. For
experiment active culture was prepared in nutrient broth by the transfer of
loopfull cells of stock cultures into test tube. Same procedure is done for
each sample of bacterial cultures, as well as for each fungal cultures. And
kept in incubator at 37°C for 24 hours. Agar disc diffusion was performed for
this assay.
Method for Disc
Diffusion
Nutrient
agar media was used for check the antibacterial activity of given samples.
Prepare media with specific concentration (13g/L) in dist. Water. Sterilize the
media and petriplates, pour the media into petriplate and wait till it
solidify. After solidify the media use the sterilized cotton bud for swabbing
the bacterial culture on solid plates. And discs of different concentrations
(15, 20, 25, 30 µl) were placed on media by the use of sterilized forceps.
Incubate the plates into incubator at 37°C for 24 hours than observe the zone
of inhibition, measure the diameter which determines the growth of bacteria and
activity of that specific concentration of plant extract on disc. For check the
antifungal activity of given samples we used Muller-Hinton agar (MHA) medium.
Sterilize the media and petriplates and pour the media into petriplate and wait
till it solidify. When the media had been solidified we use the sterilized
cotton bud for swabbing the fungus culture on solid plates. And discs of
different concentrations (15, 20, 25, 30 µl) were placed on media by the use of
sterilized forceps. Incubate the plates into incubator at 37°C for 3 days than
observe the zone of inhibition, measure the diameter which determine the growth
of fungus and activity of that specific concentration of plant extract on disc.
Results
Antibacterial
and antifungal activity of ethanol extract of Aloe Vera is checked against various pathogens and results are
given bellow.
Antibacterial activity of Leaf extract against gram positive
bacterial
In Antibacterial activity of Leaf
extract against gram positive Bacillus subtitis shows 15mm, Bacillus cereus 13mm, Bacillus megaterium 14.5mm,
Streptococcus pyogenes 13 and Staphylococcus aureus 14mm as shown in fig 1.
Zone of inhibition at low concentrations are also shown in fig 1. And also
shown in graph 1 height zone of inhibition is 15 for Bacillus subtitis and
lowest zone of inhibition is 13 for Bacillus cereus and Streptococcus pyogenes at concentration of 30 µl.
Antibacterial activity of Leaf extract against gram negative
bacterial
In
Antibacterial activity of Leaf
extract against gram negative bacterial strains, Aloe vera shows high
antibacterial activity against Echerichia coli and Agrobacterium
tumefacins which is noted that around 18mm zone of inhibition and shows
lowest zone of inhibition among all our used strains which is around 11.5mm at
concentration of 30µl. zone of inhibition measured at concentration of 10, 20
25 and 30 µl are also shown in fig 2 Enterococcus
faecalis, Bacillus subtitis and Bacillus megaterium shows good result,
means that Aloe vera have good
antibacterial activity against our used gram positive strains.
Antibacterial activity of Root extract against gram positive
bacteria
Antibacterial activity of Root
extract against gram positive bacteria Aloe
Vera shows good antibacterial activity against Bacillus subtitis,
Bacillus megaterium and
Enterococcus faecalis which is noted around 16mm and lowest zone of
inhibition is 13.5 against Bacillus cereus at concentration of 30
µg as shown in fig 3.
Antibacterial activity of Root extract against gram positive
bacteria
Aloe vera root extract
also testified good results against gram negative bacteria. In this study Antibacterial
activity of Root extract against gram negative bacteria Agrobacterium
tumefacins noted zone of
inhibition of around 17.5mm. Aloe vera root extraxt also shows good antibacterial
activity against Escherichia coli, shows zone of inhibition is around
16mm. Zone of inhibition measured at concentration of 10, 20, 25 and 30
µl are also shown in table. Shown in
fig 4.
Antifungal activity of Leaf extract against pathogenic
fungal strains
Antifungal activity of A.vera is
also observed against several pathogenic fungus at different concentrations.
Both the ethanol extracts of leaf and roots are applied on culture of different
fungus by disc diffusion method. Leaf
extract shows excellent results against
fuserium oxysporum and Aspergillus niger 18.5mm
and 18mm zone of inhibition respectively but the measure of zone of
inhibition against other used fungus is also shows good results as given in fig
5.
Antifungal activity of Root extract against pathogenic
fungal strains
Antifungal
activity of Root extract against pathogenic fungal strains also shows good
results. Zone of inhibition is measured and at different concentrations. Zone
of inhibition against fuserium oxysporum is measured around 19mm which shows
that ethanol extract of A.vera Roots have good antifungal activity. Aspergillus
niger also shows good antifungal results zone of inhibition is measured around
18mm. other used fungus also shows good results as shown in fig 6.
Fig 1. Anti-bacterial activity of leaf extract
against gram+ve bacteria
Fig 2.
Anti-bacterial activity of
leaf extract against gram-ve bacteria
Fig 3.
Anti-bacterial activity of
root extract against gram+ve bacteria
Fig 4. Antibacterial activity of Root
extract against gram negative bacteria
Fig 5. Antifungal activity of Leaf extract
against pathogenic fungal strains
Fig 6. Antifungal activity of Root extract
against pathogenic fungal strains
Discussion
In our present
study ethanol extract of Aloe vera was investigated for
antibacterial and anti-fungal activity. Inhibitory effect of all the used
concentrations of both the leaves extract and root extract shows varying degree
of inhibition of growth of used bacterial and fungal pathogens as shown in
above figures (1-6). Different concentrations of ethanol extract (15, 20, 25
and 30µl)
of leaves and root is applied of bacterial and fungal growth by the use
of disc diffusion method. With the increase of concentration, zone of
inhibition is also increased maximum zone of inhibition is examined on highest
concentration. The ethanol gel extracts
of A. vera root and leaves showed highest degree of activity around 19 and ranges from
11-19 at highest concentration against the selected pathogens. Aqueous, acetone and ethanol
extracts of the A. vera gel is used
against some human and plant pathogens is
examined by disc diffusion method for check the antimicrobial activity and
phytocostituents (Ibrahim et al., 2011). Among the three extracts
used by Ibrahim et al, acetone and
ethanol extracts noted
significant antimicrobial activity against all used
pathogens. As compared to ethanolic and aqueous, Acetone extract was found
quite impressive in antibacterial and antifungal activity. A. barbadensis leaf gel components for
antimicrobial activity are studied by Cock (2008). RP-HPLC was done for
fractionate the Methanolic extracts of A. barbadensis inner leaf gel,
and a panel of bacteria and fungi is used for test the inhibitory effect of
resultant fractions (Cock 2008). Antimicrobial Activity of Aloe
barbadensis Miller Leaf Gel Components 4:2). Antimicrobial activity of ethanolic extract
of leaf and gel is compared against Trichophyton mentagraphytes, P. aeruginosa, S. aureus, T. schoeleinii, C. albicans and M. canis in this antimicrobial activity, it has
been found that S. aureus is
inhibited by both the leaf and gel extract. T. mentagrophytes isonly inhibited by gel, while C.
albicans and P. aeruginosa both are inhibited by leaf extract (Agarry and Osho 2005). A
study was also conducted by Thiruppathi et
al in which he used A. vera juice
with different solvents viz, ethyl
acetate, petroleum ether, hexane and ethanol to determine the antimicrobial
activity. Following Gram positive bacteria (S. aureus, B. subtilis) and gram negative bacteria (P.
aeruginosa, E. coli, K.pneumoniae) are used for test the antimicrobial
activity. Ethyl acetate and ethanol extract shows more antimicrobial activity
which is (1-9mm) and (7-12mm) respectively. But the petroleum ether extract
shows least inhibitory effect around 2mm (Guillette
et al., 1991). Manos-6-phosphate
shows a role in the healing of wound (Davis et
al,. 1994), bradykinin-degrading glycoproteins may shows anti-inflammatory
effect (Yagi et al., 1987). For
antiviral properties anthraquinones have been studied from various plants
(Sydiskis et al., 1991). In this
study The bacterial and fungal strains used for study antimicrobial activity
are usually involve with the incidence of urogenital tract, tonsillitis, scarlet fever, rheumatic fever,
gastrointestinal tract and wound infection. These potent herbal remedies
play a big advancement in fungal infection therapies and for its safe use
especially in immunocompromised patients. The present of sponin, tanins,
alkaloids, laktine and anthroquinones in Aloe vera extract may be play an
important role in antifungal activity, since the action of antibacterial and
antifungal of these phytochemicals have been well documented (Deeni and Hussain
, 1991; Shale et al 1999). Furthermore,
due to confirmation of popular use, the testified result of this study shows
that extract of this plant could represent a good, nontoxic, less expensive
than allopathic drugs and new source of antibacterial and antifungal activity. To investigate and isolate these compounds
and to study their principles and their mechanism of action further studies are
still in progress.
CONCLUSION
Its
hope that this research can lead to create some possible vehicles Used to
develop new and more potent Natural antimicrobials. The research is
Identification of biologically active compounds and evaluate the mechanism of
action of A. vera gel extract is
related to certain organisms with human diseases. The results of this present
study shows the importance of Aloe Vera
in control of microbial infection and also used of this plant in folk medicines
for the treatment of various diseases. And pay attention on the importance of
Aloe Vera and to select it in further research and discovery of new bioactive
compounds. The result of this study shows the ethanol extract of Aloe Vera have
good antimicrobial properties even that it shows MIC at very low used
concentration. And this study shows that we can use Aloe Vera as antimicrobial
agent in new drugs for treatment of infectious disease in human. The results of
this research have been developed particularly sensitive to a variety of
bacteria the Gram-negative pathogen, Gram-positive pathogens and some fungal
pathogens. Inhibition Insulation compounds has clearly demonstrated their
usefulness to various pathogenic microorganisms. It is elucidated that the
application of plants in traditional medicine in the treatment of various
diseases caused by these pathogenic strains. Plants used in conventional
medicine, as well as plants used in the treatment of various diseases of these
pathogenic strains. In addition, identification of these antimicrobial compounds
enhances their growth by studying the structure/activity of new antimicrobial
Conflict of Interest
There
is no conflict of interest between authors.
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