Applications of Some Natural Active Extracts
for Cereal Storage Improvement
Abdelazim SAA1, Ahmed NB2 and Mohamed GS3
1 Department of Field Crop Technology Research, Agriculture Research Centre, Egypt.
2Department of Food Toxicology and Contaminants, National Research Centre, Egypt
3Arid Lands Cultivation Research Institute, City of Scientific Research and Technological Application, Egypt
Submission: July 02, 2018; Published: November 16, 2018
*Corresponding author: Abdelazim Sayed Abdelazim, Department of Field Crop Technology Research, Food Technology Research Institute, Agri culture Research Centre, Giza, Egypt.
How to cite this article: Abdelazim SAA, Ahmed NB, Mohamed GS. Applications of Some Natural Active Extracts for Cereal Storage Improvement. Nutri Food
Sci Int J. 2018; 7(5): 555723. DOI: 10.19080/NFSIJ.2018.07.555723.
The impact of some plant extract as natural antioxidant antimicrobial agents and their toxic (Arabic gum, pomegranate peels and Propolis) were evaluated. Phenolic contentwas228.2±17mg GAE/g in Pomegranate peels extract and 87.1±2.3, 9.7±0.1mg GAE/g for Propolis and Arabic gum, respectively. Total flavonoid ranged from 24.41±1.7 to 42.15±2.83mg Catechol/g in Propolis and pomegranate peels respectively, while it was not present in the Arabic gum. Our results show the presence of a strong association between the scavenging activity against the stable ABTS, DPPH, FRAP radical and total phenol for extracts. Propolis was the most effective extract in either minimal inhibition concentration (MIC) or minimal bacterial concentrations (MBC) values of Propolis were ranged (1.2-1.5mg/ml between 1.5-1.9mg/ml respectively) which considered closed to the standard antibiotic values. Data represented in the order of the antifungal activities for use substrates as Propolis >pomegranate peels > Arabic gum. The high antibacterial impact of Propolis was recorded on the bacterial strain of staphylococcus aureus. The pomegranate peel extract had the higher reducing effect on Aflatoxin B1 than Propolis extract and Arabic gum extract (36.39±3.84, 14.93±2.31, 5.70±4.37(ng/g) respectively, however, for AFG1 the pomegranate peels recorded higher reducing ratio more than the two other extracts. The coating rice with pomegranate peels extract had the highest resistance toward the fungal growth during storage than Propolis and Arabic gum extract, respectively. The amount evaluated of aflatoxins on the rice grains recorded a variation in the extract's ability to limit the aflatoxins presence on grains. Were ordering as pomegranate peels extract > Propolis extract > Arabic gum extract. We can confirm the possibility of using these substances in functional foods.
Mycotoxins, which are fungal secondary metabolites produced during toxigenic fungi metabolism process, are very harmful compound could be found in the feed and food products . Mycotoxin may also the main causes of various types of a health hazard for humans and animals. It consists of a large group of compounds, recently it has reached about four hundred types of toxic materials. Each species of fungi had the ability to excrete one or more of toxic substances, in the same times, one toxin may produce by more than one fungi. It may contaminate food and feed chains which deem the main reason of toxic impacts in the higher creatures when consumed impure commodities . However, like all over the world, Mycotoxins are a public health worry for Egyptian populations. Cereals, crops, Agricultural products are the major food products suffering from mycotoxin contamination.
Toxigenic fungi are at most out righted by Aspergillus, Penicillium, Alternaria, and Fusarium, however, Aspergillus among the others is very significant fungi, it takes into consideration as a contaminant in either food/feed materials, and it is a plant pathogen. Aspergillus and Penicillium fungi are mycotoxins producer. Otherwise, toxigenic fungi which recorded to be high grown on cereals
are Alternaria, Penicillium, Fusarium, Cladosporium, Stachybotrys, Trichoderma, Acremonium and Paecilomyces [3,4]. Ultimately, there are four groups of aflatoxins AFB1, AFB2, AFG1, and AFG2 and its two metabol ism derivatives AFM1 and AFM2; from which AFB1 is the extreme potency aflatoxins that incentive the health problems to human and animal. Aflatoxins are a toxic compound to human and animal and the main reason for different .
Aflatoxins are particularly a problem in hot and dry cultivated areas, aflatoxins expansion is exacerbated due to the factors affecting of its existence which involves the drought, pests’ infection, and the delayed harvest. As one more point, insufficient drying and poor post-harvest handling are also included as a factors increase the aflatoxin infection . Furthermore, Mycotoxin production by fungi could happen in the storage area causing spoilage in cereals, subsequently actually creating a health problem when it consumed by animals or human. Another hazard factor is the cropping system where previous crop and soil plowing could effect on the resultant crop safety .
Aflatoxin B1 has classified as group A carcinogens, according to IARC classification report for carcinogenic substances. The modern suggested techniques for aflatoxins reduction are the
exclusion of aflatoxin-producing fungi by non-toxigenic strains
either simultaneously or with an interval time difference.
Different techniques for aflatoxin reducing has applied in the
feed using aflatoxin’s binders and additives in animal feed. Also,
chemical treatment of contaminated crops is a wonderful method
for mycotoxin decreases like the ozone fumigation and treatment
with ammonia. Recently, biocontrol of toxigenic fungi to suppress
its growth was utilized to reduce the mycotoxin excretion
amounts. Moreover, application of probiotic bacteria to reduce
aflatoxin uptake record a positive result in many cases. Use of
the superabsorbent polymers and the essential oils in mycotoxin
binding reported as a successful application, avoiding mycotoxin
contamination-hazard in animal feed .
Antioxidants are components which prohibit the oxidation
process either in food substances or body fluids. The free radical
activity has been involved in cancer, tissue damages, aging, and
destruction of DNA. Recently, there has been an increase to
examine more substances that can defend against these reactive
materials species and play a significant role in disease inhibition
. Antioxidants play an important role in decreasing mycotoxins
impacts in food and feed products [5,9]. Many substances had
antioxidation effects such as phenolic components in plant
materials, also, flavonoids, plant extracts, and food residual
sources. The plant extracts considered a rich material in bioactive
substances, it could use to include in the bio-films which
applied to reduce mycotoxin contamination that happens in cereal
and crops .
The pomegranate (Punicagranatum L.) is a shrub plant mainly
grew in the hot and moderate weather. It is widely spread in North
Africa, Mediterranean area, India, and Southern East area of Asia.
Pomegranate fruits are rich in bioactive substances including the
phytochemicals like tannins, anthocyanins, and ellagic acid, and
other phenolics. It has been utilized widely in folk medicine in
many countries all over the world. Anthocyanin in pomegranate
has also is a natural dye which preferred in some types of food
products. Moreover, the Propolis is a natural sticky component
possessed by the bees from different plants and flowers roots.
Chemically the propolis takes notice as a better source of
natural antioxidants and antibacterial . Propolis includes an
assortment of chemical components like coumarins, steroids,
polyphenols, sesquiterpene, quinines, and inorganic materials.
Phenolic compounds are the most significant compounds found
in propolis,in particular flavonoids and phenolic acids . Propolis
has described having various biological effectiveness, including
the antibacterial, antifungal, anticancer, antiviral and antitumor
characteristics. Consequently, propolis utilized in pharmaceuticals
and nutraceuticals to promote health and prevent diseases like
pre-cancer, inflammation, hemorrhagic, and chronic diseases
. Arabic Gum is an edible, dried, the sticky exudate substance
from the specific types of tree stems and branches. Oral intake of
Arabic gum has reported to prolonging various health benefits, it
may serve as an antioxidant, anticancer, and antitumor compound
. Gum Arabic deems an essentially effective due to the
powerful antioxidant characteristics.
The aim of the present study was to evaluate the antimicrobial,
antifungal, antioxidant, and ant mycotoxigenic potency of
Pomegranate peels, Propolis, and Arabic gum against some types
of food harmful. These hazards included the toxigenic fungi,
pathogenic bacteria, and mycotoxins. The result of this study
will assist to increase the shelf-life of food and feed products
encompass the cereals and its based products. This study is the
utilized of food grade extracts with lower cost to enhance the
main food products safety and quality. The extraction applied
in this study not only safe, cheap, and easy applied; it will also
increase the nutritional values of the final products.
Preparation of extracts: Extracts of pomegranate peels
(PGE), propolis (PPE), and Arabic gum (AGE)prepared using
isopropyl: water (1:1 v/v) as eco-friendly solvents. Waterisopropyl
(v/v) was added to the finely ground powders at a ratio
of 1:10 (w/v). The mixture stirred using an overhead stirrer for
50 min at 45 °C. The extracts, then separated from the residue
by filtration through Whatman No.4 filter paper. The filtrate
concentrated under vacuum at 45 °C using a rotary evaporator.
The extra solvent was removed by freeze-drying and the dried
powder stored at -20 °C until further analyses
Total phenolic content: The Folin-Ciocalteu reagent assay
was used to determine the total phenolic content of extracts
as described by Ozsoy et al., . The total phenolic content
expressed in mg Gallic acid equivalents (GAE)/g of sample (mg/g).
All determinations performed in triplicate.
Total flavonoid content: The total flavonoid contents of
the pomegranate peels (PGE), propolais (PPE), and Arabic gum (AGE) extracts determined by a colorimetric method described
by Sakanaka et al. , the absorbance measured at 510nm. The
results were expressed as mg cat./g of sample. All determinations
were performed in triplicate.
DPPH radical scavenging activity: The free radical
scavenging activity of pomegranate peels (PGE), propolais (PPE),
and Arabic gum (AGE) extracts measured by the DPPH method
as proposed by Turkmen et al. . The measured conditions
recorded at 517nm with a spectrophotometer.
ABTS cation decolorization assay: ABTS radical assay used
to evaluate the ability to scavenge free ABTS radicals, based on
the protocol of Re et al. . Absorbance readings measured using
a spectrophotometer at 734nm. Results were expressed as μ mol
of trolox equivalents (TE) per g sample from a standard curve
developed with Trolox. All determinations performed in triplicate.
Ferric reducing ability (FRAP)assay: The FRAP assay was
done according to according to Hwang & Do-Thi . Readings of
the colored product, absorbent measured at 593nm. The standard
curve was prepared using Trolox and the results were expressed
as mMTorlox equivalent (TE/g sample).
Determination of minimal inhibition concentration of
extracts: The minimal inhibitory concentration (MIC) value is
determined as the lowest concentration of extract that didn’t give
any visible bacterial growth. Each assay carried out in triplicate.
The MIC test quantified the antimicrobial activity of the extract, it
was done as the method described by Sakanaka et al., .
Determination of minimal fungicidal concentration
of extracts: The hypha growth inhibition test can be used to
determine the antifungal activity of the extracts against fungal
strains as previously described by . The concentration
required to give 50% inhibition of hyphen growth IC50will be
calculated from the regression equation. Nystatin can be used as
a positive control.
Determination of several types of extraction on fungal
growth: Yeast extract sucrose (YES) used to examine the effect of
each extraction method which may include several components
of the fungal growth of Aspergillus parasiticus ATTC 15517, also
the powder of the three materials examined by using 0.5g of each
as additional material in liquid media. The liquid media of YES
consists of 15g yeast extract, 150g sugar, and completely to one
literusing de-ionize double distilled water. The inhibition effect
represented as the loss of the fungal growth in the presence of
extracts against the control growth.
Preparation of standards for aflatoxin: The standard of
Aflatoxins received as dry films or crystals to container of dry
aflatoxins B, G, add a volume of the following solvents: methanol:
acetonitrile (9:1) calculated to give a concentration as ng/ml.
HPLC Chromatography: One hundred microliters of the
samples were injected into the HPLC column. The mobile phase
was an acetonitrile: water: acetic acid solution (51:47:2, v/v). The
flow rate was 1ml/min. High performance liquid chromatography
(HPLC) system consisted of Waters Binary Pump Model1525,
Model Waters 1500 Rheodyne Manual Injector, Waters 2475
Multi-Wavelength Fluorescence Detector, and a data workstation
with software Breeze. A Phenomenex Column C18, dimensions:
250× 4.6mm, particle size: 5μm, from Waters Corporation (USA)
as well as Microfiber Filters, 11cm, product ID: 31955, VICAM
Company (Sweden), were used.
Detoxification methods: The extracts prepared by using
aqueous isopropyl, the extracted materials concentrated to near
dried, then freeze-dried used to convert it as powder materials,
5mg of each extract concentrate was dissolved in 0.5mL in Dimethyl
sulphoxide (DMSO), this value used to inject in the plate
wells or in the plate disks as a detoxification application against
either pathogenic bacteria or toxigenic fungi [21,22].
Total fungal count of toxigenic fungi inoculated to rice
with several treatments before and after 60 days of storage:
To apply the results of the study, the antifungal ability of each
extract of PGE, PPE, and AGE were applied on rice grain samples.
A rice samples equal to 150g were brushed with a water solution
of each extract for 3 min. After that, the samples were dried in
hot air oven at 45 °C for 5-6 h to reach 11% moisture content.
The samples of the three extracts treatments, side of the control
without treatment were packed in a sterilized polyethylene bag.
Each type of extract treatment was inoculated by nine strains of
mycotoxigenic fungi (one strain/one bag/one treatment). The
initial count of each inoculated strain at 25 °C was recorded as
before treatment and at the end of the storage period (60 days)
the final count of each strain recorded as after treatment value.
Application of some natural active extracts on rice grains
as cereal food preservatives: To apply the results of the study,
the antifungal ability of each extract of PGE, PPE, and AGE were
applied on rice grain samples. A rice samples equal to 150g were
brushed with a water solution of each extract for 3 min. After
that, the samples were dried in hot air oven at 45 °C for 5-6 h to
reach 11% moisture content. The samples of the three extracts
treatments, side of the control without treatment were packed
in a sterilized polyethylene bag. The bags of the three treatments
and the control were inoculated with a high producing toxic strain
of Aspergillus parasiticus ITEM 11 and incubated at 25 °C for 15
days. The result of aflatoxins amount that excreted on the rice
seeds were evaluated using HPLC techniques.
The total phenolic content (TPC) and total flavonoid contents
(TFC) of the three extracts comprised PGE, PPE, and AGE have
evaluated. The results were recorded as shown in Figure 1. The
TPH was 228.2±17, 87.1±2.3, 9.7± 0.1mg GAE/g for PGE, PPE, and AGE, respectively. However, The TFC recorded at values
of 24.41±1.7 and 42.15±2.83mg Catechol/g for Propolis and
pomegranate peels, respectively; otherwise, it was not detected
in the Arabic gum. Health benefits of the bioactive molecules
included the flavonoids was exhibited and its potent antioxidant
impact had proved . The TPH and the TF were significantly
different among different extracts as reported in Figure 1. Our
results are compatible with several recent studies [24-26], these
studies reported the highest values of TPH in pomegranate
peels and Propolis. There are various reports of TPH and TFC in
pomegranate peels with a wide difference in the published results
is remarked. This could be the result of geographical, cultivar [27-
29]. Variations in the results might be also due to the different
extraction procedure used in the experiments, particularly due to
the type and the concentration of the starting extraction solvent.
Fawole et al.,  noted that the aqueous ethanol was effective in
the TPH extraction of PGP with values ranged from 180 to 290mg
GAE/g. The TPH in PP ranged from 79.8 to 156.3μg/g, the average
being 119.5μg/g. As a result of this discussion, aqueous solvent
extraction technique could be a superior system for the effective
bioactive compound extraction from PGP (Figure 1).
Antioxidant activity of three extracts of PGE, PPE, and AGE
measured using three parallel test assays, the results are presented
in Table 1. The values indicate that; the IC50 of extracts is ordering
descending at P=0.05 from PGE to AGE. The antioxidant potency
of PGE, PPE, and AGE evaluated using three different assays, these
were DPPH, ABTS, and FRAP reducing ability. Among the extracts
analyzed, PGE recorded the greatest antioxidant activity by the
three methods. Low IC50 corresponds to a strong inhibitory
capacity of DPPH, ABTS, FRAP radical, the highest IC50 is recorded
for the AG.
IC50: Concentration of sample required for 50% inhibition. Results are expressed as mean of three experiments ± SD.
In a previous study; the PGE had the highest antioxidant
activity among the peels, pulp and seed fractions of 28 kinds of
fruits commonly consumed in China, as determined by FRAP
assay that described in the study of Guo et al., . While
Pagliarulo, et al.  demonstrated that the methanol extract of
pomegranate peels had the highest antioxidant activity among
ethyl acetate, methanol, and water extracts. Moreover, Li et al.
 reported the aqueous methanol to be more effective than
each solvent alone. The antioxidant activity potential of Propolis
may be due to the presence of diverse phytochemical compounds,
mainly flavonoids and phenolic acids . The decrease of DPPH
radical by the different plant extracts has been attributed by many
authors, at the presence of phenolic compounds which yield
simply to reduce protons . Our results recorded the presence
of a strong association between the scavenging activities against
the stable ABTS, DPPH, FRAP radical and total phenol for extracts.
This could the main reason in the antimicrobial, antifungal and
antimycotoxigenic impact of these types of extracts. These results
are in agreement with results of Abdelazim  who found that
Silymarin can be used as natural antioxidants and antimicrobial
activity in the food industry (Table 1).
The MIC values of the three extracts for the raw materials
of PGPE, PPE, and AGE evaluated to explain the antimicrobial
impact. Moreover, minimal bacterial concentration (MBC) were
determined to explore the ability of these extracts to apply as
antibacterial components in food productions. Four pathogenesis
bacterial strains were applied to examine the inhibition of its
growth in the presence of these GRAS extracts, Amoxicillin
antibiotic was utilized as a standard reference to compare the
antibacterial effects. Represented as the data in Table 2, Propolis
was the most effective extract in either minimal inhibition
concentration. MIC and MBC values of propolis were ranged
between (1.2-1.5mg/ml and1.5-1.9mg/ml respectively) which
considered closed to the standard antibiotic values. Among the
three extracts, Arabic gum extraction showed the lowest values
either for MIC or the MBC on the pathogenic bacterial strains in
this experiment. The results of MIC and MBC values of the three
types of the extracts were applied against three types of pathogenic
strains, these strains were Pseudomonase aerugnosa ATCC 9027,
Enterococcus faecalies ATCC47077, and Staphylococcus aureus
NCTC 10788. The strain of Enterococcus faecalies ATCC47077
recorded a high resistance value either in MIC or in MBC for the
three types of extracts.
On the other hands, some of the previous studies reported
an antibacterial activity of ethanolic extracts of the Propolis,
the results manifested a high antibacterial action against grampositive
bacteria with a MIC ranging from 0.2 to 0.78 mg/mL, also
it was reported an elevated antibacterial activity against gramnegative
bacteria Salmonellae Terica [25,26] (Table 2).
Antifungal effect of several types of the extraction methods of
Arabic gum, Propolis, and pomegranate peels were applied on YES
media against the fungal growth of Aspergillus parasiticus ATTC
15517 showed in Table 3).The extracts were ass to the YES liquid
media with a concentration of 10mg/ml for each material, also the
powder of the three materials was examined by using 0.5g of each
as additional material in liquid media. The results represented a
good inhibition impact of the pomegranate peels on the fungal
growth for the aqueous extraction methods as well as for the
powder addition in the media (Table 3).
*Data were represented as mean of values ±SD.The weight of fungal growth on liquid media is recorded in grams
Antifungal activity of pomegranate peels, propolis extracts and
Arabic gum against tested fungus strains (mm) showed in Table 4.
In order to the need to ensure the results, the antifungal of these
plant materials, extracts were tested by other antifungal method.
Plate inhibition zone assay of the extracts against four toxigenic
fungi strains were applied to explore the variations recorded
between the several materials in the antifungal effect, this will
be useful to determine the suitable amounts which aimed to be
applied as food additive to enhance the good qualities of food
against the fungal contaminations. The data represented in the
order of the antifungal activities for used substrates as Propolis
> Pomegranate peels>Arabic gum. The extract of Propolis showed
a closed result to the standard antifungal compound (Nystatine).
The high antifungal impact of Propolis was recorded on the
Fusarium fungi (Table 4).
*Data were represented as mean of values ±SD. Each value represents the mean of three replicates.
Antibacterial characteristics of the three materials, extracts
were measured as an inhibition zone on them against the bacterial
growth of four pathogenic strains on potato dextrose agar
supplemented by Nystatine as antifungal antibiotic to suppress
the fungi and the results showed in Table 5. Plate inhibition zone
assay of the extracts against four bacterial strains were applied to
explore the variations recorded between the several materials in
the antibacterial impact, this will help to evaluate the application
of these extracts during the food manufacturing to support the
good qualities of food products as well as its expected application
in food commodities coating against the bacterial spoilage.
The data represented in the order of antibacterial activities for
use substrates as Propolis >pomegranate peels>Arabic gum.
The extract of Propolis showed a closed result to the standard
antifungal compound (Amoxicillin). The high antibacterial impact
of Propolis was recorded on the bacterial strain of Streptococcus
aureus (Table 5).
Data were represented as mean of values ±SD.Each value represents the mean of three replicates.
In a previous study, The PP reported to had an antibacterial
activity against some strains of testing pathogens such as;
Salmonella enteritidis ATCC 13076, Staphylococcus aureus ATCC
13565 Escherichia coli ATTC 25923, Listeria monocytogenes and
Bacillus subtilis NCTC 8236 . Antimicrobial activity of PP also
reported by using several types of solvents (Ethanol, Acetone,
Toluene). Otherwise, the change in the pH values of the resultant
extract at three different pH values (6,7,8) showed a widely range
of PP antibacterial activity . This result agrees with Chacko
and Estherlydia & Labyad et al., [36,37], they described exhibited
antibacterial activity of PGP against various Gram-positive and
Gram-negative bacteria of pomegranate peels was characterized
by the highest antibacterial activity against of Shigellastrain of
pathogenic bacterial .
Notwithstanding; Rather & Rajagopal  extracted
phenolics from dried powdered PP with various solvents
(methanol, ethyl acetate, chloroform, and water) and revealed the
antimicrobial activity of methanolic extract against Escherichia
coli, Pseudomonas sp., Klebsiella sp., vancomycin and methicillin
resistant Staphylococcus aureus.
Reducing the impact of iso-propanol-water extracts of
Pomegranate peels, Propolis and Arabic gum on aflatoxin B1 and
aflatoxin G1 were exanimated in the YES fungal growth of liquid
media, the amount of AFB1 and AFG1 were determined in the
control flask of Aspergillus paraciticus strain ATCC 11517 and the
results illustrated in Figure 2. The toxin amount was indicated the
control aflatoxins amount of AFB1 and AFG1. While, other flasks
were supported by the extracted materials at a concentration of
10mg/ml in the growth media. Using the apparatus of HPLC, the
reducing amount of aflatoxins was recorded against the amount
that excreted in the control flask. The reducing amount here was
reflected either the inhibition effect of the extracted material on
the fungal excretion metabolites or it could be referred to the chemical reaction happen during the extraction present in growth
media. The PGE had the higher reducing effect on Aflatoxin B1
and G1 more than PPE and AGE (36.39 ±3.84, 14.93±2.31, 5.70±
4.37(ng/g)) and (34.37±0.6 than 21.04±0.18 and 17.34±0.88
(ng/g)) respectively, however, for AFG1 the recorded the higher
reducing ratio for each of the extracts compared to control.
The AGE recorded as the lower effect than PGEand PPE)
52.9±0.88than 42.56±0.6 and 50.53±0.18 (ng/g( respectively on
both Aflatoxin B1and Aflatoxin G1. Notwithstanding, the recovery
for the aflatoxins from AG powder precipitated in the YES media
after the experimental time was not applied to explain if the
toxin could recover from the powder or not. Maybe the effect of
the pomegranate peel extract is higher than the other extracts to
cause the high content of polyphenolic compound (Figure 2).
To gain the benefits of using these extracts as antimicrobial
and antifungal components, it has applied as a brushing coat on
the rice grains then the grains dried before packed in polyethylene
bags. These bags stored for 60 days before the fungal count
calculated. At the initial time; the grains inoculated by one strain
of fungi for each bag and the log CFU/g of rice recorded as (before
value), while at the end of the storing period the log CFU/g of rice
evaluated as (after value).The reducing values of the log CFU/g
indicated the power of the extract type as anti-mycotic material
which help to enhancement the grain safety during the storage
period. The results in Table 6 & Figure 3 showed a high powerful
of each extract to reduce the log CFU/g of fungi during the storage
period. The PGE coating material appeared as an excellent coated
material against the nine strains of toxigenic fungi. while AGE
exhibited the lowest type of coated material to resist the fungal
growth on the stored rice. These results support the application of
PGE as a cheap source of bioactive substances to reduce the fungal
infection in the stored grain when it is applying as coating film.
The results gained from this experiment was in agreement with
 (Table 6).
Value represented at the mean value of five replecates. The LSD= 2.189
As an application to convert the results of this experiment
to increase the agriculture, sustainable production and increase
the food safety, the extracts of PGE, PPE, and AGE had applied
to coat the rice grains and inoculated by A. parasiticus ITEM
11 strain which recorded as a high producing strain of the four
types of aflatoxins. According to the recorded results; PGE was
the effective extract that able to reduce the toxin excretion on the
stored rice grain during the optimum time of aflatoxin excretion
by the fungi (about 15 days). The amount evaluated of aflatoxins
on the rice grains recorded a variation in the extracts ability to
limit the aflatoxins presence on grains. The reducing ratio were
ordering as PGE, PPE, AGE, respectively (Figure 4).
Pomegranate peels, Propolis and Arabic gum had considerable
levels of polyphenolic compounds. Their chemical characteristics
induce in general a strong bactericidal action against
Pseudomonase aerugnosa ATCC 9027 and Staphylococcus aureus
NCTC 10788, Propolis, Pomegranate peels and Arabic gum had a
reducing effect on Aflatoxin B1 and Aflatoxin G1 (ng/g). Presented
results of this study demonstrated high biological potential of
these extracts. Statistical analysis showed high correlation among
the contents of investigating classes of compounds and biological
activity of prepared extracts. All in all, these results confirmed
that extract of Pomegranate peels, Propolis and Arabic gum might
indeed be a potential source of biological compounds. We can
could be reported can use the Propolis, Pomegranate peels and
Arabic gum as plant natural antioxidant, antimicrobial agents and
their toxics and as functional foods.