https://doi.org/10.52973/rcfcv-e34508
Received: 28/08/2024 Accepted: 02/11/2024 Published: 23/12/2024
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Revista Científica, FCV-LUZ / Vol. XXXIV, rcfcv-e34508
ABSTRACT
Citrullus lanatus thunb. (watermelon) belonging to the Curcubitaceae
family, is the most important crops worldwide. The present work aims
to estimate the polyphenolic content, anti-inammatory and antiulcer
properties, in addition to the antioxidant activity of ethanolic extract
of watermelon esh fruit. The ethanolic extract of watermelon fruit
contains secondary metabolites, polyphenols, avonoids and tannins.
Reducing power test and 2,2’-azino-bis(3-ethylbenzothiazoline-6-
sulfonic acid) (ABTS) scavenging assay were used to measure the
antioxidant activity. In the two tests that were examined, watermelon
ethanolic extract demonstrated a potent antioxidant potential.
Pretreatment of rats with watermelon extract at the doses of 200
and 600 mg·kg
-1
demonstrated signicant anti-inammatory effect
and decreased carrageenan induced paw edema, with inhibition
percentages of 57.24 ± 3.18 and 69.00 ± 2.80%, respectively. However,
the doses 50, 200, and 600 mg·kg
-1
of watermelon extract pretreated
to rats reduced gastric mucosal injury on ethanol induced acute
gastric ulcer with percentages protection of 75.01 ± 0.77, 92.38 ± 2.98
and 95.01 ± 0.81% compared to omeprazole (95.92%). This study
revealed that watermelon fruit consumption could be a promising
anti-inammatory and gastroprotective agents.
Key words: Citrullus lanatus thunb; flavonoids; inflammation;
oxidative stress; polyphenols; tannins; ulcer
RESUMEN
Citrullus lanatus thunb. (sandía), perteneciente a la familia
Curcubitaceae, es el cultivo más importante a nivel mundial. El presente
trabajo tiene como objetivo estimar el contenido polifenólico, las
propiedades antiinamatorias y antiulcerosas, además de la actividad
antioxidante del extracto etanólico de pulpa de sandía. El extracto
etanólico de sandía contiene metabolitos secundarios, polifenoles,
avonoides y taninos. Se utilizaron pruebas de poder reductor y
ensayo de eliminación Ácido 2,2-azino-bis(3-etil benzotiazolina-6-
sulfónico) (ABTS) para medir la actividad antioxidante. En las dos
pruebas examinadas, el extracto etanólico de sandía demostró
un potente potencial antioxidante. El pretratamiento de ratas con
extracto de sandía a las dosis de 200 y 600 mg·kg
-1
demostró un
efecto antiinamatorio signicativo y disminuyó el edema de la pata
inducido por carragenina, con porcentajes de inhibición de 57,24 ± 3,18
y 69,00 ± 2,80 %, respectivamente. Sin embargo, las dosis de 50, 200
y 600 mg·kg
-1
de extracto de sandía pretratado a ratas redujeron la
lesión de la mucosa gástrica en la úlcera gástrica aguda inducida por
etanol con porcentajes de protección de 75,01 ± 0,77, 92,38 ± 2,98 y
95,01 ± 0,81 % en comparación con omeprazol (95,92 %). Este estudio
reveló que el consumo de sandía podría ser un prometedor agente
antiinamatorio y gastroprotector.
Palabras clave: Citrullus lanatus thunb; avonoides; inamación;
estrés oxidativo; polifenoles; taninos; úlcera
Exploring the chemical prole, antioxidant, in vivo anti-inammatory and
gastroprotective properties of watermelon (Citrullus lanatus thunb.) in rats
Explorando el perl químico, antioxidante, antiinamatorio in vivo y propiedades
gastroprotectoras de la sandía (Citrullus lanatus thunb.) en ratas
Amel Bouaziz* , Saliha Djidel , Assia Bentahar , Nihed Barghout , Seddik Khennouf , Saliha Dahamna
University Ferhat Abbas Setif 1, Faculty of Nature and Life Sciences, Laboratory of Phytotherapy Applied to Chronic Diseases. Setif, Algeria.
*Corresponding author: a.bouaziz@univ-setif·dz
Effect gastroprotective potential of watermelon in rats / Bouaziz et al. _____________________________________________________________
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INTRODUCTION
Free radicals are byproducts of regular metabolism within cells.
Reduction of pathogens, wound healing, and cell regeneration are
among the physiological processes that are positively impacted by
the production of a small quantity of reactive oxygen species (ROS).
However, excessive ROS production upsets the body’s equilibrium
and causes oxidative tissue damage [1]. Oxidative stress is a state
imposed by an excess of ROS or a reduction in antioxidant defense
mechanisms. It is closely linked to the pathogenesis of numerous
diseases as cardiovascular diseases, diabetes, atherosclerosis,
inammation, and peptic ulcer [2].
Gastric ulcer is an injury of the stomach mucosa that may be
caused by an imbalance in the substances that protect the mucous
(mucous-bicarbonate protective layer, prostaglandins, growth factors,
cells renewal, mucosal blood ow) and the aggressive factors (acid,
pepsin, free radicals) [3]. Various factors including Helicobacter
pylori exposure, smoking, stress, alcohol consumption, poor diet,
and non streroidal anti-inammatory medication (NSAIDs) addiction
are implicated in the pathophysiology of gastric ulcer [4]. Notably,
proinammatory cytokines and production of free radicals have been
linked to this pathology [5]. Proton pump inhibitors, antimuscarinic
drugs, H2 receptor antagonists, and acid-independent drugs which
are triggered by antibiotics against H. pylori are the mainstays of
treatment for gastric ulcers [6]. These medications may have adverse
side effects such arrhythmia, hypersensitivity, and hematopoietic
alterations, which would limit their effectiveness [7]. Thus, research
of safe and ecient natural alternatives for gastroprotective drugs. In
this regard, medicinal plants, fruits and vegetables may be considered
as a proliferating source with a large range of biological activities.
Citrullus lanatus thunb. (watermelon) belonging to the Curcubitaceae
family, is the most important crops worldwide. It is consumed as
byproducts, such as juices, jellies, sauces, sweets and compotes
with exceptional nutritional value, and is an essential fruit in the
supply of bioactive chemicals in food for humans [8]. This fruit is used
traditionally for its cooling, aphrodisiac, astringent, strengthening,
indigestible, expectorant, diuretic properties, for blood purication,
quelling of thirst, biliousness treatment, and has benecial properties
for scabies, itches, and painful ears [9]. Watermelon esh shows
various health benets including antioxidant, antimicrobial, analgesic,
laxative, antidiabetic, anti-obesity effects and contains many dietary
antioxidants such as phenolics, carotenoids, and flavonoids, in
addition to vitamins, mineral salts, and amino acids (arginine and
citrulline). Natural substances, including ascorbic acid and lycopene,
carbohydrates, cardioglycosides, terpenoids (cucurbutacine E), oils,
and fats [10, 11, 12].
Nonetheless, little research is exploring the medicinal potential
of C. lanatus flesh in Algeria, Regarding its ability to reduce
inammation and ulcers. Further, research is needed to evaluate
the effective concentration for its function. Thus, this study aimed
to quantify the amount of polyphenols, avonoids, and tannins as
well as the antioxidant and in vivo anti-inammatory activities and
gastroprotective property on ethanol-induced ulcer model in rats of
the ethanolic extract of Algerian watermelon fruit, variety Crimson
sweet were investigated.
MATERIALS AND METHODS
Animals
The Wistar rats (Rattus norvegicus) of male sex (180-200 g) (PS 600.
R2, Germany) obtained from Pasteur institute in the capital Algiers. For
one week of adaptation, the animals were maintained under laboratory
settings (temperature of 25 ± 1°C, 55 ± 5% humidity and standard with
a 12-hour daylight cycle).They were also given access to an unlimited
supply of water and commercial rat food containing 21% of proteins.
Plant material and preparation of ethanolic extract
Watermelon was chopped in Setif province (Northeast Algeria) and
grated after being cleaned and its esh separated from the rind. The
protocol used by Markham [13] was followed in the preparation of
ethanolic extract. To maximize the extraction of phenolic chemicals, 1
kg of mixed esh was combined with 5 L of ethanol (80%) and kept for
ve days at room temperature. Following the mixture’s ltration with
Whatman paper, the ltrates were collected and concentrated using a
rotary evaporator (Buchi rotavap R-205, Switzeland) at 40°C. The crude
extract was dried in the ovenat 37°C for 72 h (Memmert UM200, Germany).
Phytochemical prole
Total polyphenols content estimation
Folin Ciocalteu method was used to evaluate the content of phenolic
compounds in the extract [14]. 100µL of watermelon extract and 500
µL of the diluted Folin-Ciocalteu reagent were combined. After 4 min,
400 µL of sodium bicarbonate solution (Na
2
CO
3
) with concentration of
7.5% was added. At 765 nm (Shimadzu UV 1800 spectrophotometer,
Japan), the absorbance was measured following 90 min at dark room
temperature. The total polyphenols content was determined, and
the data are given as milligrams equivalent of gallic acid per gram
of extract (mg GAE·g
-1
of extract).
Flavonoids content estimation
Aluminum chloride (AlCl
3
) technique was followed to quantify the
avonoids content [15]. Briey, 1 mL of watermelon extract was added to 1
mL of 2% aluminium chloride solution diluted in methanol. After incubating
for 10 min at 430 nm, the absorbance was determined. The avonoids
content was determined and the data were expressed as milligrams
equivalent of quercetin per gram of extract (mg QE·g
-1
of extract).
Tannins content estimation
The tannins content was estimated using the method of Gharzouli
et al. [16].1 mL of cow blood with absorbance of 1.6 was combined
with 1 mL of watermelon extract. After the mixture solution was left
for 20 min at room temperature, it was centrifuged for 10 min at 4000
G (Sigma 3-30K, Germany), and the absorbance of the supernatant
was read at 756 nm. The equivalent tannic acid in milligrams per
gram of extract (mg TAE·g
-1
of extract) was reported for the results.
Evaluation of in vitro antioxidant activity
2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)radical
scavenging test
Watermelon extract’ free radical scavenging property was assessed
using ABTS radical following the modied method of Re et al. [17].To
_____________________________________________________________________________Revista Cientica, FCV-LUZ / Vol. XXXIV, rcfcv-e34508
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obtain ABTS solution, a mixture of 7 mmol·L
-1
of the aqueous ABTS and
2.45 mmol·L
-1
of persulfate solution was diluted with methanol and
incubated for 16 h. After that, 1 mL of the ABTS methanolic solution
was mixed with 50 µL of watermelon extract and the absorbance
was recorded at 734 nm after 15 min. Using the following formula,
the ABTS free radical inhibition percentage (I%) was determined:
ABTS activity (%)
=
Acontrol
Acontrol
-
Asa mple
&
0
#
100
Reducing power test
Reducing power of watermelon flesh ethanolic extract was
estimated following the techinique of Chung et al. [18].The procedure
involved mixing 0.1 mL of phosphate buffered saline (0.2M, pH=6.6),
0.1 mL of potassium ferricyanide (K
3
FeCN
6
)
,
and 0.1 mL of watermelon
extract. After the mixture was incubated for 20 min at 50°C in water
bath (Memmert WNB22, Germany), 0.1 mL of 1% trichloroacetic acid
was added to stop the process and the mixture was centrifuged for 10
min at 4000 G. To 0.25 of the supernatant, 0.25 mL of H
2
O and 0.5 mL
of 0.1% Ferric chloride (FeCl
3
) were added. A 700 nm measurement,
the absorbance was determined.
In vivo anti-inammatory activity estimation
Paw edema induced by carrageenan in rats was used to evaluate
the inammation inhibition activity of watermelon ethanolic extract
according to the method described by [19]. Rats were divided into
four groups (n=5). Groups 1, 2, 3, and 4 were treated with distilled
water, indomethacin as anti-inammatory drug reference (20 mg·kg
-1
),
watermelon extract (200 and 600 mg·kg
-1
), respectively. one hour after
the pretreatment, the left subplantar hind paw was injected with 0.1 mL
of carrageenan (1% in NaCl) to cause acute inammation. Using digital
calliper, measurements of edema volume were taken at 0 h before the
inammation induction (V0) and every hour until 6 h (V t). The inhibition
percentages (I%) of paw edema was calculated as follows:
Inhibition (%)
=
Vt
-
V0
^ h
control
Vt
-
V0
^ h
control
-
Vt
-
V0
^ h
extract
(
2
#
100
Evaluation of antiulcer effect
The gastroprotecive potential of watermelon ethanolic extract
was determined according to the method of Abdulla et al. [20] with
slight modications. Five groups of rats (n=5) were formed. They
were allowed to consume water without restriction until 1 h before
to the experiment, but they had to fast for 24 h before the beginning
of experiment. Group 1 was given distilled water (5 mL·kg
-1
) and
considered as negative control; Group 2 was given proton pump
inhibitor drug; omeprazole (20 mg·kg
-1
) and considered as antiulcer
group according to Sreeja et al. [21];Groups 3, 4,and 5 were given
watermelon esh extract (50, 200, and 600 mg·kg
-1
). All of the rats’
groups were given an oral dose of absolute ethanol (2.5 mL·kg
-1
) 1
h following the extract pretreatment. After the administration
of absolute ethanol for 30 min following Mamache et al. [22],the
animals were killed with cervical dislocation and their stomachs
were taken out, opened, washed with NaCl (0.9%), and then were
taken pictures. The total area of the injuries was calculated using
image J software (Wayne Rasband, NIH, USA).The percentages of
ulceration (Ulcer index) and the preventive index (PI) were calculated
using the following formula:
Ulceration (%)
=
total mu cos a area
total ulceratio n area
&
0
×100
PI (%)
=
SU c
Uc
-
Ut
&
0
×100
Statistical analysis
Graphpad Prism version 5.00 was used to analyze all the data.
Following one-way ANOVA to ascertain group differences, Dunnet’s
test was conducted in all experiments. The ndings presented in vitro
and in vivo were expressed as mean ± standard error of mean (SEM)
and mean ± standard deviation (SD), respectively. When P<0.05, the
values were taken to be signicantly different.
RESULTS AND DISCUSSIONS
Polyphenols, avonoids, and tannins contents
The quantication of total polyphenols and avonoids contents
revealed that watermelon flesh extract contains amount of
37.01 ± 2.84mg GAE·g
-1
of extract and 0.69 ± 0.08 mg QE mg·g
-1
of
extract, respectively. However, the estimated tannins concentration
was 49.77 mg TAE.g
-1
of extract. Phenolic content of C. lanatus extract
was superior to that found in a Ghanian study of Neglo et al. [23] in
which methanolic fraction contained 0.010 ± 0.001 mg·g
-1
of extract.
The fresh juice of watermelon was found to contain 17-20 mg of
polyphenols per 100 mL. Also, hydrolysable phenols, which make up
63% of all phenolic compounds, were found in high concentrations
in watermelon peels according to phytochemical analyses of Pérez–
Jiménez and Saura–Calixto [24]. This fraction mainly contained
avanols and the acids hydroxybenzoic and hydroxycinnamic with
concentration of 1.32g·g
-1
of dry weight. The secondary metabolites
have been found to have a large variety of biological activities as
analgesic, anticancer, anti-inammatory, and antibacterial properties,
in addition to having strong antioxidant activity [25].
Antioxidant activity estimation
ABTS radical scavenging effect
ABTS test is the common spectrophotometric procedure, and it
depends on the ABTS radical’s capacity to undergo decolorization
in the addition of phytochemical antioxidants by either receiving an
electron or donating proton [26]. As seen in TABLE I, the ABTS radical
scavenging effect of C. lanatus extract signicantly (P<0.001) was
lower with inhibition concentration(IC
50
) of 0.468 ± 0.05 mg·mL
-1
than
that of butylated hydroxytoluene (BHT) (IC50 = 0.015 ± 0.0003 mg·mL
-1
).
This free radical scavenging effect may be due to the phenolic
content, as demonstrated by its capacity to extract a signicant
quantity of avonoids and polyphenols, which are in charge of many
plant species’ antioxidant properties [27].Radical scavenging is
the main way that polyphenols exert their antioxidant action [28].
Single electron transfer or hydrogen atom donation can be used to
achieveit. Furthermore, the antioxidant activity of phenolic molecule
is inuenced by factors as number and location of OH groups inside
it [29].The variability in antioxidant activity with respect to phenolic
concentration can be explained by several factors. The region in which
food plants were grown, altitude, environmental factors like irrigation,
soil, light, temperature, harvested season, exposure pathologies and
pests, industrial processing, drying, storage, and extraction technique
TABLE I
In vitro antioxidant activity
ABTS
IC
50
(mg·mL
-1
)
Ferric reducing power
EC
50
(mg·mL
-1
)
Citrullus lanatus extract 0.468 ± 0.05 *** 3.58 ± 0.04 ***
BHT 0.015 ± 0.0003 0.007 ± 0.002
Comparison was done with BHT as positive standard ; ***
P<0.001
0 1 2 3 4 5 6
0
1
2
3
4
5
6
7
8
Time (h)
Edema (mm)
untreated Group Indomethacin
200 mg·kg
-1
600 mg·kg
-1
Indomethacin 200 mg·kg
-1
600 mg·kg
-1
0
20
40
60
80
100
Inhibition (%)
*
ns
A
B
FIGURE 1. Anti-inammatory eect of watermelon extract on carrageenan induced
paw edema in rats. A: Paw edema volume (mm). B: % inhibition of edema volume.
The results are presented as mean (%) ± SEM (n=5). ns: no signicant,*: signicantly
dierent at P<0.05 vs indomethacin
Effect gastroprotective potential of watermelon in rats / Bouaziz et al. _____________________________________________________________
4 of 8
are some of the factors that may affect the antioxidant potential and
polyphenolic content of food plants [30, 31].
Ferric reducing power
The strong absorbance of Prussian blue complex may be used to
measure the reducing power after the reduction of ferricyanide to
ferrocyanide in the mixture solution [30].
This result indicated that the ferric reducing power of C. lanatus
ethanolic extract and the positive standard (BHT) increase with their
concentration. Higher ferric reducing power was demonstrated by
increased of the absorbance reaction mixture. It was found that
the ferric reducing power of C. lanatus extract was moderate with
effective concentration (EC
50 )
of 3.58 ± 0.04 mg·mL
-1
compared to BHT
as reference standard(EC
50
= 0.007 ± 0.002 mg·mL
1
) (TABLE I) and the
difference was signicant (P<0.001).It can be seen that watermelon
esh extract has a potent reducing ability which may be due to the
presence of reductants functioning as electron donors [32]. In this
sense, polyphenols are well recognized to be good electron donors
[33], which allowing them to function as antioxidants that break
the chain and scavenge free radicals. These results suggest that
watermelon extract could be able to donate electrons to scavenge
reactive oxygen species. Antioxidant chemicals that function as
reductants stop the radical chain reaction functioning as electron
donors by giving a hydrogen atom to the metal complex [34].
the inammatory effect in the subsequent phase, which lasts from
3 to 6 h [36]. Thus, the phenolics present in the ethanolic extract
of C. lanatus esh may be principally responsible for any potential
anti-inammatory properties. The explicative and strong mechanism
of avonoids’ anti-inammatory action may be their inhibition of
proinammatory mediators. This is also consistent with several
studies that claim the potent anti-inammatory properties of different
plants that include chemical components like polyphenols, which
function by blocking prostaglandin pathways [37]. Furthermore,
it was shown the compound Cucurbitacin E, which was extracted
from C. lanatus var. citroids, inhibits reactive oxygen species
(RNS), cyclooxygenase (COX), and the synthesis of nitric oxide in
macrophages activated by lipopolysaccharids and interferon γ
(IFNγ) [38].
Consuming watermelon and L-arginine which is one of the
constituents of watermelon increased the liver’s expression
of endothelial nitric oxide while that of fatty acid synthase,
cyclooxygenase 2 was decreased. The ndings are consistent with
the theory that arginine and watermelon intake modify pertinent
gene expression to enhance cardiovascular disease risk variables
such as inammation, antioxidant capacity, and lipid prole [39].
In vivo anti-inammatory activity
The carrageenan induced paw edema technique was used to assess
the acute anti-inammatory property of the watermelon ethanolic
extract [19].The thikness of rat’s paw was measured within 6 h after
the injection of carrageenan. As shown in FIG. 1.A, the pretreatment
with C. lanatus ethanolic extract (200 and 600 mg·kg
-1
) signicantly
decreased the edema volume induced by carrageenan within 3 h when
compared with the NSAIDs medication, indomethacin (20 mg·kg
-1
).
Injection of carrageenan into the hind paw induced an increase in
edema reaching its maximum at 6 h with edema thickness of the
control group was 5.78 ± 0.80 mm. This edema was reduced by
indomethacin to 3.08 ± 0.06 mm and reduced by the two doses of
C. lanatus extract to 4.68 ± 0.74 and 4.19 ± 0.85 mm, respectively.
These last two doses of watermelon extract presented an inhibition
percentages of 57.24 ± 3.18 and 69.00 ± 2.80%, respectively (FIG. 1.B).
The effect of the 600 mg·kg
-1
dose was similar to that of indomethacin
(I% = 81.30 ± 6.54%).
Sulphated sugars found in carrageenan cause biphasic reactions
involving the activation of the complement system and inammatory
mediators [35]. Histamine, serotonin, and kinins mediate the
inflammatory impact in the first and second hours, whereas
prostaglandin synthesis and cyclooxygenase 2 activation mediate
FIGURE 2. Eect of pretreatment with watermelon extract on the gross appearance of the gastric mucosa in ethanol induced ulceration. (A): Absolute ethanol, (B): watermelon
extract (50 mg·kg
-1
), (C): watermelon extract (200 mg·kg
-1
), (D): watermelon extract (600 mg·kg
-1
), (E): omeprazole (20 mg·kg
-1
)
FIGURE 3. Eect of pretreatment with watermelon extract on ethanol induced gastric
lesions. Ulceration percentage. The results are represented as mean % ± SEM (n=5).
ns: no signicant, ***: signicantly dierent at P<0.001 vs control or omeprazole
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Gastroprotective activity of watermelon extract
Macroscopic examination
Rats pretreated with absolute ethanol displayed a wide range
of macroscopic lesions (FIG. 2A) and severe hemorrhagic lineage,
varying in size and scattered throughout the glandular portion of
the stomachs, suggesting the formation of a fully developed gastric
ulcer. In comparison to the ethanol treated control, pretreatment with
watermelon extract (50, 200, and 600 mg·kg
-1
) reduced the damage
to the gastric mucosa dose dependently (FIG .2B, C, D). Additionally,
the stomach mucosal folds attened and the regions of gastric
ulceration were lessened in the rats given omeprazole (20 mg·kg
-1
)
prior to ethanolic induction (FIG. 2E).
Evaluation of antiulcerative activity
As shown in FIG. 3, administration of ethanol caused severe gastric
lesions with a UI value of 31.96 ± 2.41% in ethanol treated group.
While rats treated with C. lanatus extract at 50, 200, and 600 mg·kg
-1
doses on gastric mucosal injury induced by ethanol exhibited a
statistically a signicant decrease in the number and the severity
of gastric injuries. The protective indexes of C. lanatus extract were
75.01 ± 0.77, 92.38 ± 2.98 and 95.01 ± 0.81%. These values were compared
to omeprazole with protective index of 95.92 ± 1.98 (FIG. 4).
In this work, the results agree with those of Shama et al. [40], who
claimed that the aqueous extract of C. lanatus var citroides esh exerted a
protective effect on pyloric ligation and indomethacin induced ulceration.
The antiulcer effect of C. lanatus extract could be attributed to its
capacity to scavenge free radicals, reduce acid secretory parameters,
and enhance the gastric mucosal barrier. The presence of bioactive
components in the extracts may increase protective factors, preventing
damage to the gastric mucosa and maintaining its integrity [41].
FIGURE 4. Eect of pretreatment with watermelon extract on ethanol induced
gastric lesions. Protective index expressed in %. The results are represented as
mean % ± SEM (n=5). ns: no signicant, ***: signicantly dierent at P<0.001 vs
control or omeprazole
Effect gastroprotective potential of watermelon in rats / Bouaziz et al. _____________________________________________________________
6 of 8
Previous research has indicated that active principle with antiulcer
properties include avonoids, alkaloids, tannins, soponins, and
terpenoids [42]. Flavonoids are polyphenolic compounds that
stimulate the release of stomach mucus and are also known to have
antioxidant properties. Tannins are known to “tar” the stomach
mucosa’s outermost layer, making it less permeable and more
resistant to irritants and chemicals as well as mechanical harm [43].
According to this study, C. lanatus may have anti-inammatory activity
that helps in the prevention of mucosa from lesions.
CONCLUSIONS
This study showed that flesh ethanolic extract from crimson
sweet, a variety of watermelon largely consumed in Algeria contains
secondary metabolites; polyphenols, avonoids , and tannins and
demonstrated strong radical scavenging and reducing power.
Moreover, the ethanolic extract of watermelon esh demonstrated
potent anti-inammatory and antiulcer properties. These ndings
suggest that watermelon consumption could be useful alternative
treatment for the management of inammatory and ulcer diseases.
Conict of interest
The contributors attest that there is no conicts of interest.
Ethical approvals
The European Union Guidelines with Number of 2010/63/Eu
were followed in this study for all experiments and authorized by
the Algerian Association of Sciences committee under number law
88-08 of 1988.
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